Power-to-weight ratio
Encyclopedia
Power-to-weight ratio is a calculation commonly applied to engine
Engine
An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...

s and mobile power sources to enable the comparison of one unit or design to another. Power-to-weight ratio is a measurement of actual performance of any engine or power sources. It is also used as a measurement of performance of a vehicle
Vehicle
A vehicle is a device that is designed or used to transport people or cargo. Most often vehicles are manufactured, such as bicycles, cars, motorcycles, trains, ships, boats, and aircraft....

as a whole, with the engine's power
Power (physics)
In physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...

output being divided by the weight (or mass
Mass
Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...

) of the vehicle, to give a metric that is independent of the vehicle's size. Power-to-weight is often quoted by manufacturers at the peak value, but the actual value may vary in use and variations will affect performance.

The inverse of power-to-weight, weight-to-power ratio (power loading) is a calculation commonly applied to aircraft, cars, and vehicles in general, to enable the comparison of one vehicle performance to another. Power-to-weight ratio is equal to powered acceleration
Acceleration
In physics, acceleration is the rate of change of velocity with time. In one dimension, acceleration is the rate at which something speeds up or slows down. However, since velocity is a vector, acceleration describes the rate of change of both the magnitude and the direction of velocity. ...

multiplied by the velocity of any vehicle.

## Power-to-weight (specific power)

The power-to-weight ratio (Specific Power) formula for an engine (power plant) is the power
Power (physics)
In physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...

generated by the engine divided by weight
Weight
In science and engineering, the weight of an object is the force on the object due to gravity. Its magnitude , often denoted by an italic letter W, is the product of the mass m of the object and the magnitude of the local gravitational acceleration g; thus:...

of the engine as follows:

A typical turbocharged V8 diesel engine might have an engine power of 330 hp and a weight of 835 pounds (378.7 kg), giving it a power-to-weight ratio of 0.65 kW/kg (0.40 hp/lb).

Examples of high power-to-weight ratios can often be found in turbines. This is because of their ability to operate at very high speeds. For example, the Space Shuttle
Space Shuttle
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...

's main engines use turbopump
Turbopump
A turbopump is a gas turbine that comprises basically two main components: a rotodynamic pump and a driving turbine, usually both mounted on the same shaft, or sometimes geared together...

s (machines consisting of a pump driven by a turbine engine) to feed the propellants (liquid oxygen and liquid hydrogen
Liquid hydrogen
Liquid hydrogen is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.To exist as a liquid, H2 must be pressurized above and cooled below hydrogen's Critical point. However, for hydrogen to be in a full liquid state without boiling off, it needs to be...

) into the engine's combustion chamber. The original liquid hydrogen turbopump is similar in size to an automobile engine (weighing approximately 775 pounds (351.5 kg)) and produces 72,000 hp
Horsepower
Horsepower is the name of several units of measurement of power. The most common definitions equal between 735.5 and 750 watts.Horsepower was originally defined to compare the output of steam engines with the power of draft horses in continuous operation. The unit was widely adopted to measure the...

(53.6 MW) for a power-to-weight ratio of 153 kW/kg (93 hp/lb).

### Physical interpretation

In classical mechanics
Classical mechanics
In physics, classical mechanics is one of the two major sub-fields of mechanics, which is concerned with the set of physical laws describing the motion of bodies under the action of a system of forces...

, instantaneous power
Power (physics)
In physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...

is the limiting value of the average rate of change of work done per unit time as the time interval Δt approaches zero.

If the work to be done is rectilinear motion of a body with constant mass
Mass
Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...

, whose center of mass
Center of mass
In physics, the center of mass or barycenter of a system is the average location of all of its mass. In the case of a rigid body, the position of the center of mass is fixed in relation to the body...

is to be accelerated along a straight line to a speed and angle with respect to the centre and radial
Spherical coordinate system
In mathematics, a spherical coordinate system is a coordinate system for three-dimensional space where the position of a point is specified by three numbers: the radial distance of that point from a fixed origin, its inclination angle measured from a fixed zenith direction, and the azimuth angle of...

of a gravitational field
Gravitational field
The gravitational field is a model used in physics to explain the existence of gravity. In its original concept, gravity was a force between point masses...

by an onboard powerplant
Powertrain
In a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive...

, then the associated kinetic energy
Kinetic energy
The kinetic energy of an object is the energy which it possesses due to its motion.It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes...

to be delivered to the body is equal to

where: is mass of the body is speed of the center of mass
Center of mass
In physics, the center of mass or barycenter of a system is the average location of all of its mass. In the case of a rigid body, the position of the center of mass is fixed in relation to the body...

of the body, changing with time.

The instantaneous mechanical pushing/pulling power delivered to the body from the powerplant is then

where: is acceleration of the center of mass
Center of mass
In physics, the center of mass or barycenter of a system is the average location of all of its mass. In the case of a rigid body, the position of the center of mass is fixed in relation to the body...

of the body, changing with time. is linear force - or thrust - applied upon the center of mass of the body, changing with time. is velocity
Velocity
In physics, velocity is speed in a given direction. Speed describes only how fast an object is moving, whereas velocity gives both the speed and direction of the object's motion. To have a constant velocity, an object must have a constant speed and motion in a constant direction. Constant ...

of the center of mass of the body, changing with time. is torque
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....

applied upon the center of mass of the body, changing with time. is angular velocity
Angular velocity
In physics, the angular velocity is a vector quantity which specifies the angular speed of an object and the axis about which the object is rotating. The SI unit of angular velocity is radians per second, although it may be measured in other units such as degrees per second, revolutions per...

of the center of mass of the body, changing with time.

Along an obstacle free positive inclined straight road steering an automobile
Automobile
An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...

straight ahead, positive linear acceleration will change the speed but not the direction of the vehicle.

The weight
Weight
In science and engineering, the weight of an object is the force on the object due to gravity. Its magnitude , often denoted by an italic letter W, is the product of the mass m of the object and the magnitude of the local gravitational acceleration g; thus:...

of the body is the force applied to the body to support it at rest in a uniform gravitational field
Gravitational field
The gravitational field is a model used in physics to explain the existence of gravity. In its original concept, gravity was a force between point masses...

, g. Using Newton's Second Law of Motion, then

where: is mass of the body is gravitational field (acceleration) vector

For large changes in altitude or with a body of mass significant when compared with the gravitational field
Gravitational field
The gravitational field is a model used in physics to explain the existence of gravity. In its original concept, gravity was a force between point masses...

source mass, then the gravitational field
Gravitational field
The gravitational field is a model used in physics to explain the existence of gravity. In its original concept, gravity was a force between point masses...

may no longer be considered uniform and therefore g also changes with time.
The torque
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....

from the powerplant
Powertrain
In a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive...

is accelerating the body to a desired velocity of motion while lifting the weight of the body, overcoming friction
Friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and/or material elements sliding against each other. There are several types of friction:...

through the powerplant and upon the surface of the body (e.g. rolling resistance
Rolling resistance
Rolling resistance, sometimes called rolling friction or rolling drag, is the resistance that occurs when a round object such as a ball or tire rolls on a flat surface, in steady velocity straight line motion. It is caused mainly by the deformation of the object, the deformation of the surface, or...

and skin friction), and overcoming other drag
Drag (physics)
In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity...

from the motion of the body through fluids (e.g. air, water). The degree in which the deliverable torque associated with the body overcomes the force of gravity upon the body and yields a net positive linear climbing acceleration, or mechanical advantage
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. Ideally, the device preserves the input power and simply trades off forces against movement to obtain a desired amplification in the output force...

, is then

where: is mass of the body is linear speed of the center of mass
Center of mass
In physics, the center of mass or barycenter of a system is the average location of all of its mass. In the case of a rigid body, the position of the center of mass is fixed in relation to the body...

of the body, changing with time. is powerplant acceleration of the center of mass of the body, changing with time. is gravitational acceleration of the center of mass of the body.
is force of friction
Friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and/or material elements sliding against each other. There are several types of friction:...

within powerplant and upon surface of the body.
Drag equation
In fluid dynamics, the drag equation is a practical formula used to calculate the force of drag experienced by an object due to movement through a fully enclosing fluid....

is force of drag
Drag (physics)
In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity...

.

If the friction
Friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and/or material elements sliding against each other. There are several types of friction:...

and drag
Drag (physics)
In fluid dynamics, drag refers to forces which act on a solid object in the direction of the relative fluid flow velocity...

loses are negligible, then the powerplant
Powertrain
In a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive...

will convert essentially all its power to either delivering kinetic energy
Kinetic energy
The kinetic energy of an object is the energy which it possesses due to its motion.It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes...

to the body or lifting the weight of the body. To meet this ideal, techniques include low rolling resistance
Rolling resistance
Rolling resistance, sometimes called rolling friction or rolling drag, is the resistance that occurs when a round object such as a ball or tire rolls on a flat surface, in steady velocity straight line motion. It is caused mainly by the deformation of the object, the deformation of the surface, or...

tyres, sufficient tyre inflation, obstacle free path, straight asphalt
Asphalt
Asphalt or , also known as bitumen, is a sticky, black and highly viscous liquid or semi-solid that is present in most crude petroleums and in some natural deposits, it is a substance classed as a pitch...

road, low automotive aerodynamic drag area
Automotive aerodynamics
Automotive aerodynamics is the study of the aerodynamics of road vehicles. The main concerns of automotive aerodynamics are reducing drag , reducing wind noise, minimizing noise emission, and preventing undesired lift forces and other causes of aerodynamic instability at high speeds...

, well lubricated
Lubricant
A lubricant is a substance introduced to reduce friction between moving surfaces. It may also have the function of transporting foreign particles and of distributing heat...

powertrain
Powertrain
In a motor vehicle, the term powertrain or powerplant refers to the group of components that generate power and deliver it to the road surface, water, or air. This includes the engine, transmission, drive shafts, differentials, and the final drive...

and a low loss mechanical transmission
Transmission (mechanics)
A machine consists of a power source and a power transmission system, which provides controlled application of the power. Merriam-Webster defines transmission as: an assembly of parts including the speed-changing gears and the propeller shaft by which the power is transmitted from an engine to a...

to run the engine at a speed that corresponds with the engine peak output power. The mechanical advantage
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. Ideally, the device preserves the input power and simply trades off forces against movement to obtain a desired amplification in the output force...

is then simply

Power is only delivered if the powerplant is in motion, and is transmitted to cause the body to be in motion. It is typically assumed here that mechanical transmission allows the powerplant to operate at peak output power. This assumption allows engine tuning to trade power band
Power band
The power band of an engine or electric motor refers to the range of operating speeds under which an the engine or motor is able to operate efficiently...

width and engine mass for transmission complexity and mass. Electric motor
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

s do not suffer from this tradeoff. The power advantage or power-to-weight ratio is then

where: is linear speed of the center of mass
Center of mass
In physics, the center of mass or barycenter of a system is the average location of all of its mass. In the case of a rigid body, the position of the center of mass is fixed in relation to the body...

of the body.

Power-to-weight ratio is relative to a uniform gravitational field
Gravitational field
The gravitational field is a model used in physics to explain the existence of gravity. In its original concept, gravity was a force between point masses...

. Normalising to any arbitrary gravitational field
Gravitational field
The gravitational field is a model used in physics to explain the existence of gravity. In its original concept, gravity was a force between point masses...

yields the specific power or power-to-mass ratio which is then

The power-to-weight ratio is typically calculated from power and mass
Mass
Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...

, although mass
Mass
Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...

is usually measured as weight
Weight
In science and engineering, the weight of an object is the force on the object due to gravity. Its magnitude , often denoted by an italic letter W, is the product of the mass m of the object and the magnitude of the local gravitational acceleration g; thus:...

on a calibrated weighing scale
Weighing scale
A weighing scale is a measuring instrument for determining the weight or mass of an object. A spring scale measures weight by the distance a spring deflects under its load...

. Values are then expressed in units power per unit force exerted on unit mass in standard gravity
Standard gravity
Standard gravity, or standard acceleration due to free fall, usually denoted by g0 or gn, is the nominal acceleration of an object in a vacuum near the surface of the Earth. It is defined as precisely , or about...

. Use of kg (kilogram)
Kilogram
The kilogram or kilogramme , also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram , which is almost exactly equal to the mass of one liter of water...

and lb (pound)
Pound (mass)
The pound or pound-mass is a unit of mass used in the Imperial, United States customary and other systems of measurement...

rather than kgf (kilogram-force)
Kilogram-force
A kilogram-force , or kilopond , is a gravitational metric unit of force. It is equal to the magnitude of the force exerted by one kilogram of mass in a gravitational field...

, SI unit
International System of Units
The International System of Units is the modern form of the metric system and is generally a system of units of measurement devised around seven base units and the convenience of the number ten. The older metric system included several groups of units...

N (Newton) or lbf (pound-force)
Pound-force
The pound force is a unit of force in some systems of measurement including English engineering units and British gravitational units.- Definitions :...

is common. The value thus expressed is the power-to-mass ratio and not the power-to-weight ratio.

The actual useful power of any traction engine can be calculated using a dynamometer
Dynamometer
A dynamometer or "dyno" for short, is a device for measuring force, moment of force , or power. For example, the power produced by an engine, motor or other rotating prime mover can be calculated by simultaneously measuring torque and rotational speed .A dynamometer can also be used to determine...

to measure torque
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....

and rotational speed
Rotational speed
Rotational speed tells how many complete rotations there are per time unit. It is therefore a cyclic frequency, measured in hertz in the SI System...

, with peak power sustained when transmission and/or operator keeps the product
Dot product
In mathematics, the dot product or scalar product is an algebraic operation that takes two equal-length sequences of numbers and returns a single number obtained by multiplying corresponding entries and then summing those products...

of torque and rotational speed maximised. For jet engines there is often a cruise speed and power can be usefully calculated there, for rockets there is typically no cruise speed, so it is less meaningful.

Peak power of a traction engine occurs at a rotational speed higher than the speed when torque is maximised and below the maximum rated rotational speed - Max RPM. A rapidly falling torque curve would correspond with sharp torque and power curve peaks around their maxima at similar rotational speed, for example a small, lightweight engine with a large turbocharger. A slowing falling or near flat torque curve would correspond with a slowly rising power curve up to a maximum at a rotational speed close to Max RPM, for example a large, heavy multi-cylinder engine suitable for cargo/hauling. A falling torque curve could correspond with a near flat power curve across rotational speeds for smooth handling at different vehicle speeds.

#### Heat engines and heat pumps

Thermal energy is made up from molecular
Sensible heat
Sensible heat is the energy exchanged by a thermodynamic system that has as its sole effect a change of temperature.The term is used in contrast to a latent heat, which is the amount of energy exchanged that is hidden, meaning it cannot be observed as a change of temperature...

kinetic energy
Kinetic energy
The kinetic energy of an object is the energy which it possesses due to its motion.It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes...

and latent
Latent heat
Latent heat is the heat released or absorbed by a chemical substance or a thermodynamic system during a process that occurs without a change in temperature. A typical example is a change of state of matter, meaning a phase transition such as the melting of ice or the boiling of water. The term was...

phase
Phase (matter)
In the physical sciences, a phase is a region of space , throughout which all physical properties of a material are essentially uniform. Examples of physical properties include density, index of refraction, and chemical composition...

energy. Heat engine
Heat engine
In thermodynamics, a heat engine is a system that performs the conversion of heat or thermal energy to mechanical work. It does this by bringing a working substance from a high temperature state to a lower temperature state. A heat "source" generates thermal energy that brings the working substance...

s are able to convert thermal energy in the form of a temperature gradient between a hot source and a cold sink into other desirable mechanical work. Heat pump
Heat pump
A heat pump is a machine or device that effectively "moves" thermal energy from one location called the "source," which is at a lower temperature, to another location called the "sink" or "heat sink", which is at a higher temperature. An air conditioner is a particular type of heat pump, but the...

s take mechanical work to regenerate thermal energy in a temperature gradient.
Heat Engine
Heat engine
In thermodynamics, a heat engine is a system that performs the conversion of heat or thermal energy to mechanical work. It does this by bringing a working substance from a high temperature state to a lower temperature state. A heat "source" generates thermal energy that brings the working substance...

/Heat Pump
Heat pump
A heat pump is a machine or device that effectively "moves" thermal energy from one location called the "source," which is at a lower temperature, to another location called the "sink" or "heat sink", which is at a higher temperature. An air conditioner is a particular type of heat pump, but the...

type
Peak Power Output Power-to-weight ratio Example Use
Wärtsilä RTA96-C
Wärtsilä-Sulzer RTA96-C
The Wärtsilä RT-flex96C is a two-stroke turbocharged low-speed diesel engine designed by the Finnish manufacturer Wärtsilä. It is currently considered the largest reciprocating engine in the world, designed for large container ships, running on heavy fuel oil...

14-cylinder two-stroke Turbo
Turbocharger
A turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...

Diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...

80,080 kW 108,920 hp 0.03 kW/kg 0.02 hp/lb Emma Mærsk
Emma Mærsk
Emma Mærsk is the first container ship in the E-class of eight owned by the A. P. Moller-Maersk Group. When she was launched in 2006, Emma Mærsk was the largest container ship ever built...

container ship
Container ship
Container ships are cargo ships that carry all of their load in truck-size intermodal containers, in a technique called containerization. They form a common means of commercial intermodal freight transport.-History:...

Suzuki
Suzuki
is a Japanese multinational corporation headquartered in Hamamatsu, Japan that specializes in manufacturing compact automobiles and 4x4 vehicles, a full range of motorcycles, all-terrain vehicles , outboard marine engines, wheelchairs and a variety of other small internal combustion engines...

538 cc V2 4-stroke gas (petrol)
Gasoline
Gasoline , or petrol , is a toxic, translucent, petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain...

outboard
Outboard motor
An outboard motor is a propulsion system for boats, consisting of a self-contained unit that includes engine, gearbox and propeller or jet drive, designed to be affixed to the outside of the transom and are the most common motorized method of propelling small watercraft...

Otto engine
Otto engine
-Otto Engine Types:There are three types of internal combustion engines designed by German inventors Nikolaus August Otto and his partner Eugen Langen. They are the 1862 compression engine, which failed, the 1864 atmospheric engine, and the engine known today as the "Gasoline Engine", the Otto...

19 kW 25 hp 0.27 kW/kg 0.16 hp/lb Runabout boats
A runabout is any small motorboat holding between four and eight people, well suited to moving about on the water. Runabouts can be used for racing, for pleasure activities like fishing and water skiing, or as a ship's tender for larger vessels...

DOE
United States Department of Energy
The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...

/NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

/0032-28 Mod 2 502 cc gas (petrol)
Gasoline
Gasoline , or petrol , is a toxic, translucent, petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain...

Stirling engine
Stirling engine
A Stirling engine is a heat engine operating by cyclic compression and expansion of air or other gas, the working fluid, at different temperature levels such that there is a net conversion of heat energy to mechanical work....

62.3 kW 83.5 hp 0.30 kW/kg 0.18 hp/lb Chevrolet Celebrity
Chevrolet Celebrity
The Chevrolet Celebrity is a mid-size car produced by the Chevrolet Division of General Motors . The Celebrity was introduced in 1981 for the 1982 model year. The Celebrity was the best-selling car in the United States in 1986...

1985
GM
General Motors
General Motors Company , commonly known as GM, formerly incorporated as General Motors Corporation, is an American multinational automotive corporation headquartered in Detroit, Michigan and the world's second-largest automaker in 2010...

6.6 L Duramax LMM (LYE option) V8 Turbo
Turbocharger
A turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...

Diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...

246 kW 330 hp 0.65 kW/kg 0.40 hp/lb Chevrolet Kodiak
Chevrolet Kodiak
Beginning with the 2003 model year, US-market models moved to a new platform with a more spacious cab based on the GM full-size vans. The 4500 and 5500 trucks had the option for Four-wheel drive. These trucks featured solid front axles, on both 4x2 and 4x4, instead of independent front suspension...

, GMC Topkick
Junkers Jumo 205A
Junkers Jumo 205
The Junkers Jumo 205 aircraft engine was the most famous of a series of diesel engines that were the first, and for more than half a century, the only successful aircraft diesel engines. The Jumo 204 first entered service in 1932. Later engines in the series were styled Jumo 206, Jumo 207 and Jumo...

opposed-piston two-stroke Diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...

647 kW 867 hp 1.1 kW/kg 0.66 hp/lb Ju 86C-1 airliner
Junkers Ju 86
The Junkers Ju 86 was a German monoplane bomber and civilian airliner designed in the early 1930s, and employed by both sides during World War II. The civilian model Ju 86B could carry 10 passengers. Two were delivered to Swissair and five to Luft Hansa...

, B&V Ha 139 floatplane
GE LM2500+
General Electric LM2500

marine turboshaft
Turboshaft
A turboshaft engine is a form of gas turbine which is optimized to produce free turbine shaft power, rather than jet thrust...

Brayton
Brayton cycle
The Brayton cycle is a thermodynamic cycle that describes the workings of the gas turbine engine, basis of the airbreathing jet engine and others. It is named after George Brayton , the American engineer who developed it, although it was originally proposed and patented by Englishman John Barber...

gas turbine
Gas turbine
A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled to a downstream turbine, and a combustion chamber in-between....

30,200 kW 40,500 hp 1.31 kW/kg 0.80 hp/lb GTS Millennium cruiseship, QM2
RMS Queen Mary 2
RMS Queen Mary 2 is a transatlantic ocean liner. She was the first major ocean liner built since in 1969, the vessel she succeeded as flagship of the Cunard Line....

ocean liner
Ocean liner
An ocean liner is a ship designed to transport people from one seaport to another along regular long-distance maritime routes according to a schedule. Liners may also carry cargo or mail, and may sometimes be used for other purposes .Cargo vessels running to a schedule are sometimes referred to as...

Mazda 13B-MSP Renesis
Mazda Wankel engine
The Mazda Wankel engines are family of car engines derived from experiments in the early 1960s by Felix Wankel, a German engineer...

1.3 L Wankel engine
Wankel engine
The Wankel engine is a type of internal combustion engine using an eccentric rotary design to convert pressure into a rotating motion instead of using reciprocating pistons. Its four-stroke cycle takes place in a space between the inside of an oval-like epitrochoid-shaped housing and a rotor that...

184 kW 247 hp 1.5 kW/kg 0.92 hp/lb Mazda RX-8
Mazda RX-8
The Mazda RX-8 is a sports car manufactured by Mazda Motor Corporation. It first appeared in 2001 at the North American International Auto Show. It is the successor to the RX-7 and, like its predecessors in the RX range, it is powered by a Wankel engine. The RX-8 began North American sales in the...

PW
Pratt & Whitney
Pratt & Whitney is a U.S.-based aerospace manufacturer with global service operations. It is a subsidiary of United Technologies Corporation . Pratt & Whitney's aircraft engines are widely used in both civil aviation and military aviation. Its headquarters are in East Hartford, Connecticut, USA...

R-4360 71.5 L 28-cylinder
Cylinder (engine)
A cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...

The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes on a wheel...

3,210 kW 4,300 hp 1.83 kW/kg 1.11 hp/lb B-50 Superfortress
B-50 Superfortress
The Boeing B-50 Superfortress strategic bomber was a post-World War II revision of the Boeing B-29 Superfortress, fitted with more powerful Pratt & Whitney R-4360 radial engines, stronger structure, a taller fin, and other improvements. It was the last piston-engined bomber designed by Boeing for...

, Convair B-36
Convair B-36
The Convair B-36 "Peacemaker" was a strategic bomber built by Convair and operated solely by the United States Air Force from 1949 to 1959. The B-36 was the largest mass-produced piston engine aircraft ever made. It had the longest wingspan of any combat aircraft ever built , although there have...

C-97 Stratofreighter
C-97 Stratofreighter
The Boeing C-97 Stratofreighter was a long range heavy military cargo aircraft based on the B-29 bomber. Design work began in 1942, with the prototype's first flight being on 9 November 1944, and the first production aircraft entered service in 1947. Between 1947 and 1958, 888 C-97s in several...

, C-119 Flying Boxcar
C-119 Flying Boxcar
The Fairchild C-119 Flying Boxcar was an American military transport aircraft developed from the World War II-era Fairchild C-82 Packet, designed to carry cargo, personnel, litter patients, and mechanized equipment, and to drop cargo and troops by parachute...

Hughes H-4 Hercules
Hughes H-4 Hercules
The Hughes H-4 Hercules is a prototype heavy transport aircraft designed and built by the Hughes Aircraft company. The aircraft made its only flight on November 2, 1947 and the project was never advanced beyond the single example produced...

"Spruce Goose"
Wright
Wright Aeronautical
Wright Aeronautical was an aircraft and aircraft engine manufacturer located in New Jersey.-History:This American company evolved from the 1909-1916 Wright Company, which merged with the Glenn L. Martin Company in 1916 to form the Wright-Martin Aircraft Corporation. Glenn Martin resigned from...

R-3350
Wright R-3350
The Wright R-3350 Duplex-Cyclone was one of the most powerful radial aircraft engines produced in the United States. It was a twin row, supercharged, air-cooled, radial engine with 18 cylinders. Power ranged from 2,200 to over 3,700 hp , depending on the model...

54.57 L 18-c
Cylinder (engine)
A cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...

s/c Turbo-compound
Turbo-compound engine
A turbo-compound engine is a reciprocating engine that employs a blowdown turbine to recover energy from the exhaust gases. The turbine is usually mechanically connected to the crankshaft but electric and hydraulic systems have been investigated as well. The turbine increases the output of the...

The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders point outward from a central crankshaft like the spokes on a wheel...

2,535 kW 3,400 hp 2.09 kW/kg 1.27 hp/lb B-29 Superfortress
B-29 Superfortress
The B-29 Superfortress is a four-engine propeller-driven heavy bomber designed by Boeing that was flown primarily by the United States Air Forces in late-World War II and through the Korean War. The B-29 was one of the largest aircraft to see service during World War II...

, Douglas DC-7
Douglas DC-7
The Douglas DC-7 is an American transport aircraft built by the Douglas Aircraft Company from 1953 to 1958. It was the last major piston engine powered transport made by Douglas, coming just a few years before the advent of jet aircraft such as the Boeing 707 and Douglas DC-8.-Design and...

C-97 S/f
C-97 Stratofreighter
The Boeing C-97 Stratofreighter was a long range heavy military cargo aircraft based on the B-29 bomber. Design work began in 1942, with the prototype's first flight being on 9 November 1944, and the first production aircraft entered service in 1947. Between 1947 and 1958, 888 C-97s in several...

prototype, Kaiser-Frazer C-119F
C-119 Flying Boxcar
The Fairchild C-119 Flying Boxcar was an American military transport aircraft developed from the World War II-era Fairchild C-82 Packet, designed to carry cargo, personnel, litter patients, and mechanized equipment, and to drop cargo and troops by parachute...

Pattakon OPRE two stroke Diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...

50 kW 70 hp 2.3 kW/kg 1.4 hp/lb
O.S. Engines 49-PI Type II 4.97 cc UAV
Unmanned aerial vehicle
An unmanned aerial vehicle , also known as a unmanned aircraft system , remotely piloted aircraft or unmanned aircraft, is a machine which functions either by the remote control of a navigator or pilot or autonomously, that is, as a self-directing entity...

Wankel engine
Wankel engine
The Wankel engine is a type of internal combustion engine using an eccentric rotary design to convert pressure into a rotating motion instead of using reciprocating pistons. Its four-stroke cycle takes place in a space between the inside of an oval-like epitrochoid-shaped housing and a rotor that...

0.934 kW 1.252 hp 2.8 kW/kg 1.7 hp/lb Model aircraft
Model aircraft
Model aircraft are flying or non-flying models of existing or imaginary aircraft using a variety of materials including plastic, diecast metal, polystyrene, balsa wood, foam and fibreglass...

A radio-controlled aircraft is controlled remotely by a hand-held transmitter and a receiver within the craft...

BMW V10 3L P84/5 2005 gas (petrol)
Gasoline
Gasoline , or petrol , is a toxic, translucent, petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain...

Otto engine
Otto engine
-Otto Engine Types:There are three types of internal combustion engines designed by German inventors Nikolaus August Otto and his partner Eugen Langen. They are the 1862 compression engine, which failed, the 1864 atmospheric engine, and the engine known today as the "Gasoline Engine", the Otto...

690 kW 925 hp 7.5 kW/kg 4.6 hp/lb Williams FW27
Williams FW27
The Williams FW27 was the Formula One car which the Williams team used during the 2005 Formula One season. While Williams was able to compete and take a couple of victories home in recent years, the FW27 proved not to be up to the same performance levels as some of the other teams' cars...

car, Formula One
Formula One
Formula One, also known as Formula 1 or F1 and referred to officially as the FIA Formula One World Championship, is the highest class of single seater auto racing sanctioned by the Fédération Internationale de l'Automobile . The "formula" designation in the name refers to a set of rules with which...

auto racing
Auto racing
Auto racing is a motorsport involving the racing of cars for competition. It is one of the world's most watched televised sports.-The beginning of racing:...

PWR
Pratt & Whitney Rocketdyne
Pratt & Whitney Rocketdyne is a United States company that designs and produces rocket engines that use liquid propellants. Pratt & Whitney Rocketdyne, headquartered in Canoga Park, California, is a division of Pratt & Whitney, itself a wholly owned subsidiary of United Technologies Corporation...

RS-24 (SSME)
Space Shuttle main engine
The RS-25, otherwise known as the Space Shuttle Main Engine , is a reusable liquid-fuel rocket engine built by Pratt & Whitney Rocketdyne for the Space Shuttle, running on liquid hydrogen and oxygen. Each Space Shuttle was propelled by three SSMEs mated to one powerhead...

Block II H2
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

Brayton
Brayton cycle
The Brayton cycle is a thermodynamic cycle that describes the workings of the gas turbine engine, basis of the airbreathing jet engine and others. It is named after George Brayton , the American engineer who developed it, although it was originally proposed and patented by Englishman John Barber...

turbopump
Turbopump
A turbopump is a gas turbine that comprises basically two main components: a rotodynamic pump and a driving turbine, usually both mounted on the same shaft, or sometimes geared together...

63,384 kW 85,000 hp 138 kW/kg 84 hp/lb Space Shuttle
Space Shuttle
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...

(STS-110
STS-110
STS-110 was a Space Shuttle mission to the International Space Station on 8–19 April 2002 flown by Space Shuttle Atlantis. The main purpose was to install the S0 Truss segment, which forms the backbone of the truss structure on the station.- Crew :...

and later)
PWR
Pratt & Whitney Rocketdyne
Pratt & Whitney Rocketdyne is a United States company that designs and produces rocket engines that use liquid propellants. Pratt & Whitney Rocketdyne, headquartered in Canoga Park, California, is a division of Pratt & Whitney, itself a wholly owned subsidiary of United Technologies Corporation...

RS-24 (SSME)
Space Shuttle main engine
The RS-25, otherwise known as the Space Shuttle Main Engine , is a reusable liquid-fuel rocket engine built by Pratt & Whitney Rocketdyne for the Space Shuttle, running on liquid hydrogen and oxygen. Each Space Shuttle was propelled by three SSMEs mated to one powerhead...

Block I H2
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

Brayton
Brayton cycle
The Brayton cycle is a thermodynamic cycle that describes the workings of the gas turbine engine, basis of the airbreathing jet engine and others. It is named after George Brayton , the American engineer who developed it, although it was originally proposed and patented by Englishman John Barber...

turbopump
Turbopump
A turbopump is a gas turbine that comprises basically two main components: a rotodynamic pump and a driving turbine, usually both mounted on the same shaft, or sometimes geared together...

53,690 kW 72,000 hp 153 kW/kg 93 hp/lb Space Shuttle
Space Shuttle
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...

#### Electric motors/Electromotive generators

An electric motor
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

uses electrical energy to provide mechanical work, usually through the interaction of a magnetic field and current-carrying conductors
Electrical conductor
In physics and electrical engineering, a conductor is a material which contains movable electric charges. In metallic conductors such as copper or aluminum, the movable charged particles are electrons...

. By the interaction of mechanical work on an electrical conductor in a magnetic field, electrical energy can be generated.
Electric motor
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

type
Weight Peak Power Output Power-to-weight ratio Example Use
Panasonic
Panasonic
Panasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...

MSMA202S1G AC servo motor
Servo motor
thumb|right|200px|Industrial servomotorThe grey/green cylinder is the [[Brush |brush-type]] [[DC motor]]. The black section at the bottom contains the [[Epicyclic gearing|planetary]] [[Reduction drive|reduction gear]], and the black object on top of the motor is the optical [[rotary encoder]] for...

6.5 kg 14.3 lb 2 kW 2.7 hp 0.31 kW/kg 0.19 hp/lb Conveyor belt
Conveyor belt
A conveyor belt consists of two or more pulleys, with a continuous loop of material - the conveyor belt - that rotates about them. One or both of the pulleys are powered, moving the belt and the material on the belt forward. The powered pulley is called the drive pulley while the unpowered pulley...

s, Robotics
Robotics
Robotics is the branch of technology that deals with the design, construction, operation, structural disposition, manufacture and application of robots...

Toshiba
Toshiba
is a multinational electronics and electrical equipment corporation headquartered in Tokyo, Japan. It is a diversified manufacturer and marketer of electrical products, spanning information & communications equipment and systems, Internet-based solutions and services, electronic components and...

660 MVA water cooled 23kV AC turbo generator
Turbo generator
A turbo generator is a turbine directly connected to an electric generator for the generation of electric power. Large steam powered turbo generators provide the majority of the world's electricity and are also used by steam powered turbo-electric ships.Smaller turbo-generators with gas turbines...

1,342 t 2,959,000 lb 660 MW 885,000 hp 0.49 kW/kg 0.30 hp/lb Bayswater, Eraring Coal
Coal-fired power station
A coal-fired power station produces electricity, usually for public consumption, by burning coal to boil water, producing steam which drives a steam turbine which turns an electrical generator...

Power station
Power station
A power station is an industrial facility for the generation of electric energy....

s
Canopy Tech. Cypress 32 MW 15 kV AC PM generator
Electrical generator
In electricity generation, an electric generator is a device that converts mechanical energy to electrical energy. A generator forces electric charge to flow through an external electrical circuit. It is analogous to a water pump, which causes water to flow...

33,557 kg 73,981 lb 32 MW 42,913 hp 0.95 kW/kg 0.58 hp/lb Electric Power station
Power station
A power station is an industrial facility for the generation of electric energy....

s
Toyota Brushless AC
Brushless AC electric motor
A Brushless AC electric motor, also known as a permanent magnet synchronous motor , is similar to a brushless DC electric motor in that the magnetic field of the rotor is supplied by the permanent magnets rather than by electromagnets. However, the stator windings of a brushless AC motor are ,...

Nd
Neodymium
Neodymium is a chemical element with the symbol Nd and atomic number 60. It is a soft silvery metal that tarnishes in air. Neodymium was discovered in 1885 by the Austrian chemist Carl Auer von Welsbach. It is present in significant quantities in the ore minerals monazite and bastnäsite...

Fe
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

B
Boron
Boron is the chemical element with atomic number 5 and the chemical symbol B. Boron is a metalloid. Because boron is not produced by stellar nucleosynthesis, it is a low-abundance element in both the solar system and the Earth's crust. However, boron is concentrated on Earth by the...

PM motor
36.3 kg 80.0 lb 50 kW 67 hp 1.37 kW/kg 0.84 hp/lb Toyota Prius
Toyota Prius
The Toyota Prius is a full hybrid electric mid-size hatchback, formerly a compact sedan developed and manufactured by the Toyota Motor Corporation...

2004
Himax HC6332-250 Brushless DC motor
Brushless DC electric motor
Brushless DC motors also known as electronically commutated motors are electric motors powered by direct-current electricity and having electronic commutation systems, rather than mechanical commutators and brushes...

0.45 kg 0.99 lb 1.7 kW 2.28 hp 3.78 kW/kg 2.30 hp/lb Radio controlled cars
Hi-Pa Drive
Hi-Pa Drive
The Hi-Pa Drive system is an electric in-wheel motor power delivery system.-Demonstration vehicles:In 2006, PML Flightlink demonstrated the Hi-Pa Drive in a series-hybrid car at the British Motor Show in London, using a Mini dubbed the "Mini QED" with its in-wheel motor at all four wheels...

HPD40 Brushless DC
Brushless DC electric motor
Brushless DC motors also known as electronically commutated motors are electric motors powered by direct-current electricity and having electronic commutation systems, rather than mechanical commutators and brushes...

wheel hub motor
Wheel hub motor
The wheel hub motor is an electric motor that is incorporated into a hub of a wheel and drives it directly.-Uses in current and future vehicles:...

25 kg 55.1 lb 120 kW 161 hp 4.8 kW/kg 2.92 hp/lb Mini
MINI (BMW)
Mini is a British automotive marque owned by BMW which specialises in small cars.Mini originated as a specific vehicle, a small car originally known as the Morris Mini-Minor and the Austin Seven, launched by the British Motor Corporation in 1959, and developed into a brand encompassing a range of...

QED HEV
Hybrid electric vehicle
A hybrid electric vehicle is a type of hybrid vehicle and electric vehicle which combines a conventional internal combustion engine propulsion system with an electric propulsion system. The presence of the electric powertrain is intended to achieve either better fuel economy than a conventional...

, Ford F150 HEV
Hybrid electric vehicle
A hybrid electric vehicle is a type of hybrid vehicle and electric vehicle which combines a conventional internal combustion engine propulsion system with an electric propulsion system. The presence of the electric powertrain is intended to achieve either better fuel economy than a conventional...

ElectriFly GPMG4805 Brushless DC
Brushless DC electric motor
Brushless DC motors also known as electronically commutated motors are electric motors powered by direct-current electricity and having electronic commutation systems, rather than mechanical commutators and brushes...

1.48 kg 3.26 lb 8.4 kW 11.26 hp 5.68 kW/kg 3.45 hp/lb Radio-controlled aircraft
A radio-controlled aircraft is controlled remotely by a hand-held transmitter and a receiver within the craft...

#### Fluid engines and fluid pumps

Fluids (liquid and gas)
Fluid
In physics, a fluid is a substance that continually deforms under an applied shear stress. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids....

can be used to transmit and/or store energy using pressure
Pressure
Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.- Definition :...

and other fluid properties. Hydraulic (liquid) and pneumatic (gas) engines convert fluid pressure into other desirable mechanical or electrical work. Fluid pumps convert mechanical or electrical work into movement or pressure changes of a fluid, or storage in a pressure vessel
Pressure vessel
A pressure vessel is a closed container designed to hold gases or liquids at a pressure substantially different from the ambient pressure.The pressure differential is dangerous and many fatal accidents have occurred in the history of their development and operation. Consequently, their design,...

.
Fluid Power
Fluid power
Fluid power is the use of fluids under pressure to generate, control, and transmit power. Fluid power is subdivided into hydraulics using a liquid such as mineral oil or water, and pneumatics using a gas such as air or other gases...

plant type
Dry Weight Peak Power Output Power-to-weight ratio
PlatypusPower Q2/200 hydroelectric
Hydropower
Hydropower, hydraulic power, hydrokinetic power or water power is power that is derived from the force or energy of falling water, which may be harnessed for useful purposes. Since ancient times, hydropower has been used for irrigation and the operation of various mechanical devices, such as...

turbine
Water turbine
A water turbine is a rotary engine that takes energy from moving water.Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. Now they are mostly used for electric power generation. They harness a clean and renewable energy...

43 kg 95 lb 2 kW 2.7 hp 0.047 kW/kg 0.029 hp/lb
PlatypusPower PP20/200 hydroelectric
Hydropower
Hydropower, hydraulic power, hydrokinetic power or water power is power that is derived from the force or energy of falling water, which may be harnessed for useful purposes. Since ancient times, hydropower has been used for irrigation and the operation of various mechanical devices, such as...

turbine
Water turbine
A water turbine is a rotary engine that takes energy from moving water.Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. Now they are mostly used for electric power generation. They harness a clean and renewable energy...

330 kg 728 lb 20 kW 27 hp 0.060 kW/kg 0.037 hp/lb
Atlas Copco
Atlas Copco
Atlas Copco is a Swedish industrial company that was founded in 1873. It manufactures industrial tooling and equipment.The Atlas Copco Group is a global industrial group of companies headquartered in Stockholm, Sweden. Revenues for 2009 totaled 63 billion SEK. The Group employs more than 33,000...

LZL 35 pneumatic motor
20 kg 44.1 lb 6.5 kW 8.7 hp 0.33 kW/kg 0.20 hp/lb
Atlas Copco
Atlas Copco
Atlas Copco is a Swedish industrial company that was founded in 1873. It manufactures industrial tooling and equipment.The Atlas Copco Group is a global industrial group of companies headquartered in Stockholm, Sweden. Revenues for 2009 totaled 63 billion SEK. The Group employs more than 33,000...

LZB 14 pneumatic motor
0.30 kg 0.66 lb 0.16 kW 0.22 hp 0.53 kW/kg 0.33 hp/lb
Bosch
Robert Bosch GmbH
Robert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...

0 607 954 307 pneumatic motor
0.32 kg 0.71 lb 0.1 kW 0.13 hp 0.31 kW/kg 0.19 hp/lb
Atlas Copco
Atlas Copco
Atlas Copco is a Swedish industrial company that was founded in 1873. It manufactures industrial tooling and equipment.The Atlas Copco Group is a global industrial group of companies headquartered in Stockholm, Sweden. Revenues for 2009 totaled 63 billion SEK. The Group employs more than 33,000...

LZB 46 pneumatic motor
1.2 kg 2.65 lb 0.84 kW 1.13 hp 0.7 kW/kg 0.43 hp/lb
Bosch
Robert Bosch GmbH
Robert Bosch GmbH is a multinational engineering and electronics company headquartered in Gerlingen, near Stuttgart, Germany. It is the world's largest supplier of automotive components...

0 607 957 307 pneumatic motor
1.7 kg 3.7 lb 0.74 kW 0.99 hp 0.44 kW/kg 0.26 hp/lb
SAI GM7 radial piston hydraulic motor
Hydraulic motor
A hydraulic motor is a mechanical actuator that converts hydraulic pressure and flow into torque and angular displacement . The hydraulic motor is the rotary counterpart of the hydraulic cylinder....

300 kg 661 lb 250 kW 335 hp 0.83 kW/kg 0.50 hp/lb
SAI GM3 radial piston hydraulic motor
Hydraulic motor
A hydraulic motor is a mechanical actuator that converts hydraulic pressure and flow into torque and angular displacement . The hydraulic motor is the rotary counterpart of the hydraulic cylinder....

15 kg 33 lb 15 kW 20 hp 1 kW/kg 0.61 hp/lb

#### Thermoelectric generators and electrothermal actuators

A variety of effects can be harnessed to produce thermoelectricity, thermionic emission
Thermionic emission
Thermionic emission is the heat-induced flow of charge carriers from a surface or over a potential-energy barrier. This occurs because the thermal energy given to the carrier overcomes the binding potential, also known as work function of the metal. The charge carriers can be electrons or ions, and...

, pyroelectricity
Pyroelectricity
Pyroelectricity is the ability of certain materials to generate a temporary voltage when they are heated or cooled. The change in temperature modifies the positions of the atoms slightly within the crystal structure, such that the polarization of the material changes. This polarization change...

and piezoelectricity
Piezoelectricity
Piezoelectricity is the charge which accumulates in certain solid materials in response to applied mechanical stress. The word piezoelectricity means electricity resulting from pressure...

. Electrical resistance
Electrical resistance
The electrical resistance of an electrical element is the opposition to the passage of an electric current through that element; the inverse quantity is electrical conductance, the ease at which an electric current passes. Electrical resistance shares some conceptual parallels with the mechanical...

and ferromagnetism
Ferromagnetism
Ferromagnetism is the basic mechanism by which certain materials form permanent magnets, or are attracted to magnets. In physics, several different types of magnetism are distinguished...

of materials can be harnessed to generate thermoacoustic energy from an electric current.
Thermoelectric Powerplant
Thermogenerator
Thermoelectric generators are devices which convert heat directly into electrical energy, using a phenomenon called the "Seebeck effect" . Their typical efficiencies are around 5-10%...

type
Dry Weight Peak Power Output Power-to-weight ratio Example Use
Teledyne
Teledyne
Teledyne Technologies Incorporated is an industrial conglomerate primarily based in the United States but with global operations. It was founded in 1960, as Teledyne, Inc., by Henry Singleton and George Kozmetsky....

238Pu
Plutonium-238

GPHS-RTG
GPHS-RTG
GPHS-RTG or General Purpose Heat Source Radioisotope Thermoelectric Generator. These are a specific American design of Radioisotope Thermoelectric Generator used on space missions GPHS-RTG or General Purpose Heat Source Radioisotope Thermoelectric Generator. These are a specific American design of...

1980
56 kg 123 lb 285 We 0.39 hp 5.09 W/kg 0.003 hp/lb Galileo probe, New Horizons
New Horizons
New Horizons is a NASA robotic spacecraft mission currently en route to the dwarf planet Pluto. It is expected to be the first spacecraft to fly by and study Pluto and its moons, Charon, Nix, Hydra and S/2011 P 1. Its estimated arrival date at the Pluto-Charon system is July 14th, 2015...

probe
Boeing
Boeing
The Boeing Company is an American multinational aerospace and defense corporation, founded in 1916 by William E. Boeing in Seattle, Washington. Boeing has expanded over the years, merging with McDonnell Douglas in 1997. Boeing Corporate headquarters has been in Chicago, Illinois since 2001...

238Pu
Plutonium-238

MMRTG
Multi-Mission Radioisotope Thermoelectric Generator are a type of Radioisotope Thermoelectric Generator developed for NASA space missions including manned ones such as the Apollo program as well as unmanned ones ranging from Viking 1 through the Mars Science Laboratory...

MSL
Mars Science Laboratory
The Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...

44.1 kg 97.2 lb 123 We 0.16 hp 2.79 W/kg 0.002 hp/lb Mars Science Laboratory
Mars Science Laboratory
The Mars Science Laboratory is a National Aeronautics and Space Administration mission with the aim to land and operate a rover named Curiosity on the surface of Mars. The MSL was launched November 26, 2011, at 10:02 EST and is scheduled to land on Mars at Gale Crater between August 6 and 20, 2012...

#### (Closed cell) batteries

All electrochemical cell batteries deliver a changing voltage as their chemistry changes from "charged" to "discharged". A nominal output voltage and a cutoff voltage are typically specified for a battery by its manufacturer. The output voltage falls to the cutoff voltage when the battery becomes "discharged". The nominal output voltage is always less than the open-circuit voltage produced when the battery is "charged". The temperature of a battery can affect the power it can deliver, where lower temperatures reduce power. Total energy delivered from a single charge cycle is affected by both the battery temperature and the power it delivers. If the temperature lowers or the power demand increases, the total energy delivered at the point of "discharge" is also reduced.

Battery discharge profiles are often described in terms of a factor of battery capacity. For example a battery with a nominal capacity quoted in ampere-hours (Ah) at a C/10 rated discharge current (derived in amperes) may safely provide a higher discharge current - and therefore higher power-to-weight ratio - but only with a lower energy capacity. Power-to-weight ratio for batteries is therefore less meaningful without reference to corresponding energy-to-weight ratio and cell temperature.
Battery
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...

type
Volts
Voltage
Voltage, otherwise known as electrical potential difference or electric tension is the difference in electric potential between two points — or the difference in electric potential energy per unit charge between two points...

Temp.
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...

Energy-to-weight ratio Power-to-weight ratio
Energizer 675 Mercury
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...

Free Zinc-air battery
Zinc-air battery
Zinc–air batteries , and zinc–air fuel cells, are electro-chemical batteries powered by oxidizing zinc with oxygen from the air. These batteries have high energy densities and are relatively inexpensive to produce...

1.4V 21 °C 1,645 kJ/kg to 0.9 V 1.65 W/kg 2.24 mA
GE Durathon™ NaMx A2 UPS
Uninterruptible power supply
An uninterruptible power supply, also uninterruptible power source, UPS or battery/flywheel backup, is an electrical apparatus that provides emergency power to a load when the input power source, typically mains power, fails...

Molten salt battery
Molten salt battery
Molten salt batteries or liquid sodium battery are a class of primary cell and secondary cell high-temperature electric battery that use molten salts as an electrolyte. They offer both a higher energy density through the proper selection of reactant pairs as well as a higher power density by means...

54.2V -40–65°C 342 kJ/kg to 37.8 V 15.8 W/kg C/6 (76 A)
Panasonic
Panasonic
Panasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...

R03 AAA Zinc–carbon battery
1.5 V 20±2 °C 47 kJ/kg 20 mA to 0.9 V 3.3 W/kg 20 mA
88 kJ/kg 150 mA to 0.9 V 24 W/kg 150 mA
Eagle-Picher
Eagle-Picher
Eagle-Picher Corporation is a privately held, American, manufacturing and resource extractive company known for its storage battery technology. It was founded in 1842 as a paint manufacturing firm using the name Eagle White Lead, and became Eagle-Picher Lead in 1916 with its merger with a lead...

SAR-10081 60Ah 22-cell Nickel–hydrogen battery
27.7 V 10 °C 192 kJ/kg C/2 to 22 V 23 W/kg C/2
165 kJ/kg C/1 to 22 V 46 W/kg C/1
ClaytonPower 400Ah Lithium-ion battery 12V 617 kJ/kg 85.7 W/kg C/1 (175 A)
Energizer 522 Prismatic Zn
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

–MnO2 Alkaline battery
Alkaline battery
Alkaline batteries are a type of primary batteries dependent upon the reaction between zinc and manganese dioxide . A rechargeable alkaline battery allows reuse of specially designed cells....

9 V 21 °C 444 kJ/kg 25 mA to 4.8 V 4.9 W/kg 25 mA
340 kJ/kg 100 mA to 4.8 V 19.7 W/kg 100 mA
221 kJ/kg 500 mA to 4.8 V 99 W/kg 500 mA
Panasonic
Panasonic
Panasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...

HHR900D 9.25Ah Nickel–metal hydride battery
1.2 V 20 °C 209.65 kJ/kg to 0.7 V 11.7 W/kg C/5
58.2 W/kg C/1
116 W/kg 2C
URI
University of Rhode Island
The University of Rhode Island is the principal public research university in the U.S. state of Rhode Island. Its main campus is located in Kingston. Additional campuses include the Feinstein Campus in Providence, the Narragansett Bay Campus in Narragansett, and the W. Alton Jones Campus in West...

1418Ah replaceable anode Aluminium–air battery model
244.8 V 60 °C 4680 kJ/kg 130.3 W/kg (142 A)
LG Chemical/CPI E2 6Ah LiMn2O4 Lithium-ion polymer battery 3.8 V 25 °C 530.1 kJ/kg C/2 to 3.0 V 71.25 W/kg
513 kJ/kg 1C to 3.0 V 142.5 W/kg
Saft 45E Fe Super-Phosphate Lithium iron phosphate battery
Lithium iron phosphate battery
The lithium iron phosphate battery, also called LFP battery, is a type of rechargeable battery, specifically a lithium-ion battery, which uses LiFePO4 as a cathode material.-History:...

3.3 V 25 °C 581 kJ/kg C to 2.5 V 161 W/kg
560 kJ/kg 1.14 C to 2.0 V 183 W/kg
0.73 kJ/kg 2.27 C to 1.5 V 367 W/kg
Energizer CH35 C 1.8Ah Nickel–cadmium battery 1.2 V 21 °C 152 kJ/kg C/10 to 1 V 4 W/kg C/10
147.1 kJ/kg 5C to 1 V 200 W/kg 5 C
Firefly Energy Oasis FF12D1-G31 6-cell 105Ah VRLA
VRLA battery
A VRLA battery is a type of low-maintenance lead–acid rechargeable battery. Because of their construction, VRLA batteries do not require regular addition of water to the cells....

battery
12 V 25 °C 142 kJ/kg C/10 to 7.2 V 4 W/kg C/10
-1 8 °C 7 kJ/kg CCA to 7.2V 234 W/kg CCA (625A)
0 °C 9 kJ/kg CA to 7.2 V 300 W/kg CA (800 A)
Panasonic
Panasonic
Panasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...

CGA103450A 1.95Ah LiCoO2 Lithium-ion battery
3.7 V 20 °C 666 kJ/kg C/5.3 to 2.75 V 35 W/kg C/5.3
0 °C 633 kJ/kg C/1 to 2.75 V 176 W/kg C/1
20 °C 655 kJ/kg C/1 to 2.75 V 182 W/kg C/1
20 °C 641 kJ/kg 2C to 2.75 V 356 W/kg 2C
Electric Fuel Battery Corp. UUV  120Ah Zinc–air fuel cell 630 kJ/kg 500 W/kg C/1
Sion Power 2.5Ah Li–S Lithium-ion battery 2.15 V 25 °C 1260 kJ/kg 70 W/kg C/5
1209 kJ/kg 672 W/kg 2C
Maxell / Yuasa / AIST
National Institute of Advanced Industrial Science and Technology
The , or AIST, is a Japanese research facility headquartered in Tokyo, and most of the workforce is located in Tsukuba Science City, Ibaraki, and in several cities throughout Japan. The institute is managed to integrate scientific and engineering knowledge to address socio-economic needs...

Nickel–metal hydride lab prototype
45 °C 980 W/kg
Toshiba
Toshiba
is a multinational electronics and electrical equipment corporation headquartered in Tokyo, Japan. It is a diversified manufacturer and marketer of electrical products, spanning information & communications equipment and systems, Internet-based solutions and services, electronic components and...

SCiB cell 4.2Ah Li2TiO3 Lithium-ion battery
2.4 V 25 °C 242 kJ/kg 67.2 W/kg C/1
218 kJ/kg 4000 W/kg 12C
Ionix Power Systems LiMn2O4 Lithium-ion battery lab model lab 270 kJ/kg 1700 W/kg
lab 29 kJ/kg 4900 W/kg
A123 Systems 26650 Cell 2.3Ah LiFePO4
Lithium iron phosphate battery
The lithium iron phosphate battery, also called LFP battery, is a type of rechargeable battery, specifically a lithium-ion battery, which uses LiFePO4 as a cathode material.-History:...

Lithium ion battery
Lithium ion battery
A lithium-ion battery is a family of rechargeable battery types in which lithium ions move from the negative electrode to the positive electrode during discharge, and back when charging. Chemistry, performance, cost, and safety characteristics vary across LIB types...

3.3 V -20 °C 347 kJ/kg C/1 to 2V 108 W/kg C/1
0 °C 371 kJ/kg C/1 to 2 V 108 W/kg C/1
25 °C 390 kJ/kg C/1 to 2 V 108 W/kg C/1
25 °C 390 kJ/kg 27C to 2 V 3300 W/kg 27C
25 °C 57 kJ/kg 32C to 2 V 5657 W/kg 32C
Saft VL 6Ah Lithium-ion battery 3.65 V -20 °C 154 kJ/kg 30C to 2.5 V 41.4 W/kg 30C (180 A)
182 kJ/kg 1C to 2.5 V 67.4 W/kg 1C
25 °C 232 kJ/kg 1C to 2.5 V 64.4 W/kg 1C
233 kJ/kg 58.3C to 2.5 V 3757 W/kg 58.3C (350A)
34 kJ/kg 267C to 2.5 V 17176 W/kg 267C (1.6kA)
4.29 kJ/kg 333C to 2.5 V 21370 W/kg 333C (2kA)

#### Electrostatic, electrolytic and electrochemical capacitors

Capacitor
Capacitor
A capacitor is a passive two-terminal electrical component used to store energy in an electric field. The forms of practical capacitors vary widely, but all contain at least two electrical conductors separated by a dielectric ; for example, one common construction consists of metal foils separated...

s store electric charge onto two electrodes separated by an electric field semi-insulating (dielectric
Dielectric
A dielectric is an electrical insulator that can be polarized by an applied electric field. When a dielectric is placed in an electric field, electric charges do not flow through the material, as in a conductor, but only slightly shift from their average equilibrium positions causing dielectric...

) medium. Electrostatic capacitors feature planar electrodes onto which electric charge accumulates. Electrolytic capacitor
Electrolytic capacitor
An electrolytic capacitor is a type of capacitor that uses an electrolyte, an ionic conducting liquid, as one of its plates, to achieve a larger capacitance per unit volume than other types. They are often referred to in electronics usage simply as "electrolytics"...

s use a liquid electrolyte as one of the electrodes and the electric double layer effect
Double layer (interfacial)
A double layer is a structure that appears on the surface of an object when it is placed into a liquid. The object might be a solid particle, a gas bubble, a liquid droplet, or a porous body. The DL refers to two parallel layers of charge surrounding the object...

upon the surface of the dielectric-electrolyte boundary to increase the amount of charge stored per unit volume. Electric double-layer capacitors extend both electrodes with a nanopourous
Nanopore
A nanopore is a small hole. It may, for example, be created by a pore-forming protein or as a hole in synthetic materials such as silicon or graphene....

material such as activated carbon
Activated carbon
Activated carbon, also called activated charcoal, activated coal or carbo activatus, is a form of carbon that has been processed to make it extremely porous and thus to have a very large surface area available for adsorption or chemical reactions.The word activated in the name is sometimes replaced...

to significantly increase the surface area upon which electric charge can accumulate, reducing the dielectric medium to nanopores and a very thin high permittivity
Permittivity
In electromagnetism, absolute permittivity is the measure of the resistance that is encountered when forming an electric field in a medium. In other words, permittivity is a measure of how an electric field affects, and is affected by, a dielectric medium. The permittivity of a medium describes how...

separator.

While capacitors tend not to be as temperature sensitive as batteries, they are significantly capacity constrained and without the strength of chemical bonds suffer from self-discharge. Power-to-weight ratio of capacitors is usually higher than batteries because charge transport units within the cell are smaller (electrons rather than ions), however energy-to-weight ratio is conversely usually lower.
Capacitor
Capacitor
A capacitor is a passive two-terminal electrical component used to store energy in an electric field. The forms of practical capacitors vary widely, but all contain at least two electrical conductors separated by a dielectric ; for example, one common construction consists of metal foils separated...

type
Capacity
Capacitance
In electromagnetism and electronics, capacitance is the ability of a capacitor to store energy in an electric field. Capacitance is also a measure of the amount of electric potential energy stored for a given electric potential. A common form of energy storage device is a parallel-plate capacitor...

Volts
Voltage
Voltage, otherwise known as electrical potential difference or electric tension is the difference in electric potential between two points — or the difference in electric potential energy per unit charge between two points...

Temp.
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...

Energy-to-weight ratio Power-to-weight ratio
ACT Premlis Lithium ion capacitor
Lithium ion capacitor
A lithium-ion capacitor is a hybrid type of capacitor. Activated carbon is used as cathode. The anode of the LIC consists of carbon material which is pre-doped with lithium ion...

2000 F
The farad is the SI unit of capacitance. The unit is named after the English physicist Michael Faraday.- Definition :A farad is the charge in coulombs which a capacitor will accept for the potential across it to change 1 volt. A coulomb is 1 ampere second...

4.0 V 25 °C 54 kJ/kg to 2.0 V 44.4 W/kg @ 5 A
31 kJ/kg to 2.0 V 850 W/kg @ 10 A
Nesccap Electric double-layer capacitor 5000 F
The farad is the SI unit of capacitance. The unit is named after the English physicist Michael Faraday.- Definition :A farad is the charge in coulombs which a capacitor will accept for the potential across it to change 1 volt. A coulomb is 1 ampere second...

2.7 V 25 °C 19.58 kJ/kg to 1.35 V 5.44 W/kg C/1 (1.875 A)
5.2 kJ/kg to 1.35 V 5,200 W/kg @ 2,547A
EEStor
EEStor
EEStor is a company based in Cedar Park, Texas, United States that claims to have developed a revolutionary new type of capacitor for electricity storage, which EEStor calls the 'Electrical Energy Storage Unit'...

EESU barium titanate
Barium titanate
Barium titanate is the inorganic compound with the chemical formula BaTiO3. Barium titanate is a white powder and transparent as larger crystals...

supercapacitor
Supercapacitor
An electric double-layer capacitor , also known as supercapacitor, supercondenser, electrochemical double layer capacitor, or ultracapacitor, is an electrochemical capacitor with relatively high energy density. Their energy density is typically hundreds of times greater than conventional...

30.693 F
The farad is the SI unit of capacitance. The unit is named after the English physicist Michael Faraday.- Definition :A farad is the charge in coulombs which a capacitor will accept for the potential across it to change 1 volt. A coulomb is 1 ampere second...

3500 V 85 °C 1471.98 kJ/kg 80.35 W/kg C/5
1471.98 kJ/kg 8,035 W∕kg 20 C

#### Fuel cell stacks and flow cell batteries

Fuel cell
Fuel cell
A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent. Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used...

s and flow cells
Flow battery
A flow battery is a form of rechargeable battery in which electrolyte containing one or more dissolved electroactive species flows through an electrochemical cell that converts chemical energy directly to electricity...

, although perhaps using similar chemistry to batteries, have the distinction of not containing the energy storage medium or fuel
Fuel
Fuel is any material that stores energy that can later be extracted to perform mechanical work in a controlled manner. Most fuels used by humans undergo combustion, a redox reaction in which a combustible substance releases energy after it ignites and reacts with the oxygen in the air...

. With a continuous flow of fuel and oxidant, available fuel cells and flow cells continue to convert the energy storage medium into electric energy and waste products. Fuel cells distinctly contain a fixed electrolyte whereas flow cells also require a continuous flow of electrolyte. Flow cells typically have the fuel dissolved in the electrolyte.
Fuel cell
Fuel cell
A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent. Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used...

type
Dry weight Power-to-weight ratio Example Use
Redflow Power+BOS ZB600 10kWh ZBB
Zinc-bromine flow battery
The zinc–bromine flow battery is a type of hybrid flow battery. A solution of zinc bromide is stored in two tanks. When the battery is charged or discharged the solutions are pumped through a reactor stack and back into the tanks. One tank is used to store the electrolyte for the positive...

900 kg 5.6 W/kg (9.3 W/kg peak) Rural Grid support
Ceramic Fuel Cells
Ceramic Fuel Cells
Ceramic Fuel Cells Ltd is an Australian fuel cell technology company, based in Melbourne. The company produces the "BlueGen" gas-to-electricity generators. CFCL's develops solid oxide fuel cell technology to provide reliable, energy efficient, high quality, and low-emission electricity from...

BlueGen MG 2.0 CHP
Cogeneration
Cogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....

SOFC
200 kg 10 W/kg
15 W/kg CHP
Cogeneration
Cogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....

MTU Friedrichshafen
MTU Friedrichshafen
MTU Friedrichshafen GmbH is a manufacturer of commercial internal combustion engines founded by Wilhelm Maybach and his son Karl Maybach in 1909...

240 kW MCFC HotModule 2006
20 t
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

12 W/kg
Smart Fuel Cell Jenny 600S 25W DMFC 1.7 kg 14.7 W/kg Portable military electronics
UTC Power
UTC Power
- About :UTC Power is a fuel cell company based in South Windsor, Connecticut. It is part of United Technologies Corporation and has been in business for over 50 years. The company has experience in all five major fuel cell technologies. The company specializes in fuel cells for buildings, buses ...

PureCell 400 kW PAFC
27,216 kg 14.7 W/kg
The vanadium redox battery is a type of rechargeable flow battery that employs vanadium ions in different oxidation states to store chemical potential energy...

80 kg 31.3 W/kg (125 W/kg peak)
Ballard Power Systems
Ballard Power Systems
Ballard Power Systems , located in Burnaby, British Columbia -- a suburb of Vancouver -- is a company that designs, develops, and manufactures zero emission proton-exchange-membrane fuel cells. This company has made a bus that uses only hydrogen fuel cells. These fuel cells combine hydrogen and...

Xcellsis HY-205 205 kW PEMFC
Proton exchange membrane fuel cell
Proton exchange membrane fuel cells, also known as polymer electrolyte membrane fuel cells , are a type of fuel cell being developed for transport applications as well as for stationary fuel cell applications and portable fuel cell applications. Their distinguishing features include lower...

2,170 kg 94.5 W/kg Mercedes-Benz
Mercedes-Benz
Mercedes-Benz is a German manufacturer of automobiles, buses, coaches, and trucks. Mercedes-Benz is a division of its parent company, Daimler AG...

Citaro O530BZ
UTC Power
UTC Power
- About :UTC Power is a fuel cell company based in South Windsor, Connecticut. It is part of United Technologies Corporation and has been in business for over 50 years. The company has experience in all five major fuel cell technologies. The company specializes in fuel cells for buildings, buses ...

/NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

12 kW AFC
Alkaline fuel cell
The alkaline fuel cell , also known as the Bacon fuel cell after its British inventor, is one of the most developed fuel cell technologies. NASA has used alkaline fuel cells since the mid-1960s, in Apollo-series missions and on the Space Shuttle. AFCs consume hydrogen and pure oxygen producing...

122 kg 98 W/kg Space Shuttle orbiter
Space Shuttle Orbiter
The Space Shuttle orbiter was the orbital spacecraft of the Space Shuttle program operated by NASA, the space agency of the United States. The orbiter was a reusable winged "space-plane", a mixture of rockets, spacecraft, and aircraft...

Ballard Power Systems
Ballard Power Systems
Ballard Power Systems , located in Burnaby, British Columbia -- a suburb of Vancouver -- is a company that designs, develops, and manufactures zero emission proton-exchange-membrane fuel cells. This company has made a bus that uses only hydrogen fuel cells. These fuel cells combine hydrogen and...

FCgen-1030 1.2 kW CHP
Cogeneration
Cogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....

PEMFC
Proton exchange membrane fuel cell
Proton exchange membrane fuel cells, also known as polymer electrolyte membrane fuel cells , are a type of fuel cell being developed for transport applications as well as for stationary fuel cell applications and portable fuel cell applications. Their distinguishing features include lower...

12 kg 100 W/kg Residential cogeneration
Ballard Power Systems
Ballard Power Systems
Ballard Power Systems , located in Burnaby, British Columbia -- a suburb of Vancouver -- is a company that designs, develops, and manufactures zero emission proton-exchange-membrane fuel cells. This company has made a bus that uses only hydrogen fuel cells. These fuel cells combine hydrogen and...

FCvelocity-HD6 150 kW PEMFC
Proton exchange membrane fuel cell
Proton exchange membrane fuel cells, also known as polymer electrolyte membrane fuel cells , are a type of fuel cell being developed for transport applications as well as for stationary fuel cell applications and portable fuel cell applications. Their distinguishing features include lower...

400 kg 375 W/kg Bus and heavy duty
Honda
Honda
is a Japanese public multinational corporation primarily known as a manufacturer of automobiles and motorcycles.Honda has been the world's largest motorcycle manufacturer since 1959, as well as the world's largest manufacturer of internal combustion engines measured by volume, producing more than...

2003 43 kW FC Stack PEMFC
Proton exchange membrane fuel cell
Proton exchange membrane fuel cells, also known as polymer electrolyte membrane fuel cells , are a type of fuel cell being developed for transport applications as well as for stationary fuel cell applications and portable fuel cell applications. Their distinguishing features include lower...

43 kg 1000 W/kg Honda FCX Clarity
Lynntech, Inc. PEMFC
Proton exchange membrane fuel cell
Proton exchange membrane fuel cells, also known as polymer electrolyte membrane fuel cells , are a type of fuel cell being developed for transport applications as well as for stationary fuel cell applications and portable fuel cell applications. Their distinguishing features include lower...

lab prototype
347 g 1,500 W/kg

### Photovoltaics

Photovoltaic Panel type Power-to-weight ratio
Thyssen Solartec
ThyssenKrupp
ThyssenKrupp AG is a German multinational conglomerate corporation headquartered in Duisburg Essen, Germany. The corporation consists of 670 companies worldwide. While ThyssenKrupp is one of the world's largest steel producers, the company also provides components and systems for the automotive...

128W Nanocrystalline
Nanocrystal solar cell
Quantum dot solar cells are an emerging field in solar cell research that uses quantum dots as the photovoltaic material, as opposed to better-known bulk materials such as silicon, copper indium gallium selenide or CdTe. Quantum dots have bandgaps that are tunable across a wide range of energy...

Si
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...

Triplejunction
Multijunction photovoltaic cell
Multi-junction solar cells or tandem cells are solar cells containing several p-n junctions. Each junction is tuned to a different wavelength of light, reducing one of the largest inherent sources of losses, and thereby increasing efficiency...

PV module
Photovoltaics
Photovoltaics is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material...

6 W/kg
Suntech
Suntech Power
Suntech Power Holdings Co., Ltd. is the world's largest producer of solar panels, with 1,800MW of annual production capacity by the end of 2010. With offices or production facilities in every major market, Suntech has delivered more than 13,000,000 solar panels to thousands of companies in more...

/UNSW HiPerforma PLUTO220-Udm 220W Ga
Gallium
Gallium is a chemical element that has the symbol Ga and atomic number 31. Elemental gallium does not occur in nature, but as the gallium salt in trace amounts in bauxite and zinc ores. A soft silvery metallic poor metal, elemental gallium is a brittle solid at low temperatures. As it liquefies...

-F22 Polycrystalline Si
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...

PV module
Photovoltaics
Photovoltaics is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material...

13.1 W/kg STP
9.64 W/kg nominal
Global Solar
Global Solar
Global Solar Energy is a manufacturer of copper indium gallium diselenide thin-film solar cells, with manufacturing operations in Tucson, Arizona, USA, and Berlin, Germany.- Technology :...

PN16015A 62W CIGS
Copper indium gallium selenide
Copper indium gallium selenide is a I-III-VI2 semiconductor material composed of copper, indium, gallium, and selenium. The material is a solid solution of copper indium selenide and copper gallium selenide...

polycrystalline thin film
Thin film solar cell
A thin-film solar cell , also called a thin-film photovoltaic cell , is a solar cell that is made by depositing one or more thin layers of photovoltaic material on a substrate...

PV module
Photovoltaics
Photovoltaics is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material...

40 W/kg
Able (AEC) PUMA 6 kW GaInP2
Indium gallium phosphide
Indium gallium phosphide , also called gallium indium phosphide , is a semiconductor composed of indium, gallium and phosphorus...

/GaAs/Ge
Germanium
Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. The isolated element is a semiconductor, with an appearance most similar to elemental silicon....

-on-Ge
Germanium
Germanium is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. The isolated element is a semiconductor, with an appearance most similar to elemental silicon....

Triplejunction
Multijunction photovoltaic cell
Multi-junction solar cells or tandem cells are solar cells containing several p-n junctions. Each junction is tuned to a different wavelength of light, reducing one of the largest inherent sources of losses, and thereby increasing efficiency...

PV array
Photovoltaics
Photovoltaics is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material...

65 W/kg
ITO/InP on Kapton foil 2000 W/kg

### Vehicles

Power-to-weight ratios for vehicles are usually calculated using Curb weight
Curb weight
Curb weight or kerb weight is the total weight of a vehicle with standard equipment, all necessary operating consumables , a full tank of fuel, while not loaded with either passengers or cargo.This definition may differ from definitions used by governmental regulatory agencies or other...

(for cars) or wet weight (for motorcycles) – in other words, excluding weight of the driver and any cargo. This could be slightly misleading, especially with regard to motorcycles, where the driver might weigh 1/3 to 1/2 as much as the vehicle itself. In the sport of competitive cycling athlete's performance is increasingly being expressed in VAM
Velocity Ascended, Metres per hour
VAM is an acronym for the Italian phrase 'velocità ascensionale media,' which translates to English as 'average ascent speed.' The term was coined coined by Dr Michele Ferrari and is the speed of elevation gain, usually stated in units of meters per hour...

s and thus as a power-to-weight ratio in W/kg. This can be measured through the use of a bicycle powermeter or calculated from measuring incline of a road climb and the rider's time to ascend it.

#### Utility and practical vehicles

Most vehicles are designed to meet passenger comfort and cargo carrying requirements. Different designs trade off power-to-weight ratio to increase comfort, cargo space, fuel economy
Fuel economy in automobiles
Fuel usage in automobiles refers to the fuel efficiency relationship between distance traveled by an automobile and the amount of fuel consumed....

, emissions control
Automobile emissions control
Vehicle emissions control is the study and practice of reducing the motor vehicle emissions -- emissions produced by motor vehicles, especially internal combustion engines....

, energy security
Energy security
Energy security is a term for an association between national security and the availability of natural resources for energy consumption. Access to cheap energy has become essential to the functioning of modern economies. However, the uneven distribution of energy supplies among countries has led...

and endurance. Reduced drag
Automotive aerodynamics
Automotive aerodynamics is the study of the aerodynamics of road vehicles. The main concerns of automotive aerodynamics are reducing drag , reducing wind noise, minimizing noise emission, and preventing undesired lift forces and other causes of aerodynamic instability at high speeds...

and lower rolling resistance in a vehicle design can facilitate increased cargo space without increase in the (zero cargo) power-to-weight ratio. This increases the role flexibility of the vehicle. Energy security considerations can trade off power (typically decreased) and weight (typically increased), and therefore power-to-weight ratio, for fuel flexibility or drive-train hybridisation
Hybrid vehicle
A hybrid vehicle is a vehicle that uses two or more distinct power sources to move the vehicle. The term most commonly refers to hybrid electric vehicles , which combine an internal combustion engine and one or more electric motors.-Power:...

. Some utility and practical vehicle variants such as hot hatch
Hot hatch
Hot hatch was originally an informal automotive industry term, shortened from hot hatchback, initially coined by the British motoring press in 1984, for a high-performance derivative of a car body style consisting of a three- or five-door hatchback automobile.Vehicles of this class are based on...

es and sports-utility vehicles reconfigure power (typically increased) and weight to provide the perception of sports car
Sports car
A sports car is a small, usually two seat, two door automobile designed for high speed driving and maneuverability....

like performance or for other psychological benefit
Criticism of sport utility vehicles
Sport utility vehicles , trucks, vans and other large vehicles are often criticized for a variety of environmental and safety-related reasons.-Safety:...

.
##### Notable low ratio
Vehicle Power Weight Power-to-weight ratio
Benz Patent Motorwagen
Benz Patent Motorwagen
The Benz Patent-Motorwagen , built in 1886, is widely regarded as the first automobile, that is, a vehicle designed to be propelled by a motor...

954 cc 1886
560 W / 0.75 bhp 265 kg / 584 lb 2.1 W/kg / 779 lb/hp
Stephenson's Rocket
Stephenson's Rocket
Stephenson's Rocket was an early steam locomotive of 0-2-2 wheel arrangement, built in Newcastle Upon Tyne at the Forth Street Works of Robert Stephenson and Company in 1829.- Design innovations :...

0-2-2
0-2-2
An 0-2-2, in the Whyte notation for the classification of steam locomotives by wheel arrangement, is one that has two coupled driving wheels followed by two trailing wheels, with no leading wheels...

steam locomotive
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

with tender 1829
15 kW / 20 bhp 4,320 kg / 9524 lb 3.5 W/kg / 476 lb/hp
CBQ
The Chicago, Burlington and Quincy Railroad was a railroad that operated in the Midwestern United States. Commonly referred to as the Burlington or as the Q, the Burlington Route served a large area, including extensive trackage in the states of Colorado, Illinois, Iowa, Kentucky, Missouri,...

Zephyr
Pioneer Zephyr
The Pioneer Zephyr is a diesel-powered railroad train formed of railroad cars permanently articulated together with Jacobs bogies, built by the Budd Company in 1934 for the Chicago, Burlington and Quincy Railroad , commonly known as the Burlington...

streamliner
Streamliner
A streamliner is a vehicle incorporating streamlining in a shape providing reduced air resistance. The term is applied to high-speed railway trainsets of the 1930s to 1950s, and to their successor "bullet trains". Less commonly, the term is applied to fully faired recumbent bicycles...

diesel locomotive
Diesel locomotive
A diesel locomotive is a type of railroad locomotive in which the prime mover is a diesel engine, a reciprocating engine operating on the Diesel cycle as invented by Dr. Rudolf Diesel...

with railcars
A railroad car or railway vehicle , also known as a bogie in Indian English, is a vehicle on a rail transport system that is used for the carrying of cargo or passengers. Cars can be coupled together into a train and hauled by one or more locomotives...

1934
492 kW / 660 bhp 94 t
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

/ 208,000 lb
5.21 W/kg / 315 lb/hp
Alberto Contador Velasco is a Spanish professional road bicycle racer for UCI ProTeam . He was the winner of the 2007 Tour de France with the team. With the Astana team he has won the 2008 Giro d'Italia, the 2008 Vuelta a España, the 2009 Tour de France, the 2010 Tour de France and won 2011 Giro...

's Verbier climb 2009 Tour de France
2009 Tour de France
The 2009 Tour de France was the 96th edition of the Tour de France, one of cycling's Grand Tours. It started on 4 July in the principality of Monaco with a individual time trial which included a section of the Circuit de Monaco...

on Specialized
Specialized Bicycle Components
Specialized Bicycle Components, more commonly known simply as Specialized, is a major American brand of bicycles and related products. It was founded in 1974 by Mike Sinyard and is based in Morgan Hill, California-History:...

bike
420 W / 0.56 bhp 62 kg / 137 lb 6.7 W/kg / 245 lb/hp
Force Motors Minidor Diesel 499 cc auto rickshaw
Auto rickshaw
An auto rickshaw or three-wheeler is a usually three-wheeled cabin cycle for private use and as a vehicle for hire. It is a motorized version of the traditional pulled rickshaw or cycle rickshaw...

6.6 kW / 8.8 bhp 700 kg / 1543 lb 9 W/kg / 175 lb/hp
PRR Q2
PRR Q2
The Pennsylvania Railroad's class Q2 comprised one prototype and twenty-five production duplex steam locomotives of 4-4-6-4 wheel arrangement....

4-4-6-4
4-4-6-4
A 4-4-6-4, in the Whyte notation for the classification of steam locomotives by wheel arrangement, is one that has four leading wheels followed by four coupled driving wheels, a second set of six coupled driving wheels and four trailing wheels....

steam locomotive
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

with tender 1944
5,956 kW / 7,987 bhp 475.9 t
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

/ 1,049,100 lb
12.5 W/kg / 131 lb/hp
Mercedes-Benz
Mercedes-Benz
Mercedes-Benz is a German manufacturer of automobiles, buses, coaches, and trucks. Mercedes-Benz is a division of its parent company, Daimler AG...

Citaro O530BZ H2
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

fuel cell bus
Fuel cell bus
A fuel cell bus is a bus that uses a hydrogen fuel cell as its power source for electrically driven wheels, sometimes augmented in a hybrid fashion with batteries or a supercapacitor....

2002
205 kW / 275 bhp 14,500 kg / 32,000 lb 14.1 W/kg / 116 lb/hp
TGV
TGV
The TGV is France's high-speed rail service, currently operated by SNCF Voyages, the long-distance rail branch of SNCF, the French national rail operator....

BR Class 373
British Rail Class 373
The British Rail Class 373 or TGV-TMST train is an electric multiple unit that operates Eurostar's high-speed rail service between Britain, France and Belgium via the Channel Tunnel...

high-speed
High-speed rail
High-speed rail is a type of passenger rail transport that operates significantly faster than the normal speed of rail traffic. Specific definitions by the European Union include for upgraded track and or faster for new track, whilst in the United States, the U.S...

electric locomotive
Electric locomotive
An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or an on-board energy storage device...

1993
12,240 kW / 16,414 bhp 816 t
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

/ 1,798,972 lb
15 W/kg / 110 lb/hp
General Dynamics
General Dynamics
General Dynamics Corporation is a U.S. defense conglomerate formed by mergers and divestitures, and as of 2008 it is the fifth largest defense contractor in the world. Its headquarters are in West Falls Church , unincorporated Fairfax County, Virginia, in the Falls Church area.The company has...

M1 Abrams
M1 Abrams
The M1 Abrams is a third-generation main battle tank produced in the United States. It is named after General Creighton Abrams, former Army Chief of Staff and Commander of US military forces in Vietnam from 1968 to 1972. The M1 is a well armed, heavily armored, and highly mobile tank designed for...

Main battle tank
Main battle tank
A main battle tank , also known as a battle tank or universal tank, is a tank that fills the heavy direct fire role of many modern armies. They were originally conceived to replace the light, medium, heavy and super-heavy tanks. Development was spurred onwards in the Cold War with the development...

1980
1,119 kW / 1500 bhp 55.7 t
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

/ 122,800 lb
20.1 W/kg / 81.9 lb/hp
BR Class 43
British Rail Class 43 (HST)
The British Rail Class 43 is the TOPS classification used for the InterCity 125 High Speed Train power cars, built by BREL from 1975 to 1982....

high-speed
High-speed rail
High-speed rail is a type of passenger rail transport that operates significantly faster than the normal speed of rail traffic. Specific definitions by the European Union include for upgraded track and or faster for new track, whilst in the United States, the U.S...

diesel electric locomotive 1975
1,678 kW / 2,250 bhp 70.25 t
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

/ 154,875 lb
23.9 W/kg / 69 lb/hp
GE
GE Transportation Systems
GE Transportation, formerly known as GE Rail, is a division of General Electric. The organization manufactures equipment for the railroad, marine, mining, drilling and energy generation industries. It is based in Erie, Pennsylvania. Locomotives are assembled at the Erie plant, while engine...

AC6000CW
GE AC6000CW
The AC6000CW is a diesel electric locomotive that is built by GE Transportation Systems. They are all used by major railroads in the United States, except for 8 units exported to BHP Billiton Iron Ore in Australia...

diesel electric locomotive 1996
4,660 kW / 6,250 bhp 192 t
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

/ 423,000 lb
24.3 W/kg / 68 lb/hp
BR Class 55
British Rail Class 55
The British Rail Class 55 is a class of diesel locomotive built in 1961 and 1962 by English Electric. They were designed for the high-speed express passenger services on the East Coast Main Line between and Edinburgh. They gained the name "Deltic" from the prototype locomotive, DP1 Deltic, which...

Napier Deltic
Napier Deltic
The Napier Deltic engine is a British opposed-piston valveless, two-stroke diesel engine used in marine and locomotive applications, designed and produced by Napier & Son...

diesel electric locomotive 1961
2,460 kW / 3,300 bhp 101 t
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

/ 222,667 lb
24.4 W/kg / 68 lb/hp
International CXT
International CXT
The International Extreme Truck or XT is a vehicle line comprising three very large pickup trucks, built on the same chassis from International from 2004-2008. The company expected business owners to account for most sales...

2004
164 kW / 220 bhp 6,577 kg / 14500 lb 25 W/kg / 66 lb/hp
Ford Model T
Ford Model T
The Ford Model T is an automobile that was produced by Henry Ford's Ford Motor Company from September 1908 to May 1927...

2.9 L flex-fuel 1908
15 kW / 20 bhp 540 kg / 1,200 lb 28 W/kg / 60 lb/hp
TH!NK City
Th!nk City
The Th!nk City is a small two-seater or 2+2-seater highway capable electric car produced by Think Global and production partner Valmet Automotive, with a top speed of and an all-electric range of on a full charge....

2008
30 kW / 40 bhp 1038 kg / 2,288 lb 28.9 W/kg / 56.9 lb/hp
Messerschmitt KR200
Messerschmitt KR200
The Messerschmitt KR200, or Kabinenroller , was a three-wheeled bubble car designed by the aircraft engineer Fritz Fend and produced in the factory of the German aircraft manufacturer Messerschmitt from 1955 to 1964.-History:...

Kabinenroller 191 cc 1955
6 kW / 8.2 bhp 230 kg / 506 lb 30 W/kg / 50 lb/hp
Wright Flyer
Wright Flyer
The Wright Flyer was the first powered aircraft, designed and built by the Wright brothers. They flew it four times on December 17, 1903 near the Kill Devil Hills, about four miles south of Kitty Hawk, North Carolina, U.S.The U.S...

1903
9 kW / 12 bhp 274 kg / 605 lb 33 W/kg / 50 lb/hp
Tata Nano
Tata Nano
The Tata Nano is an inexpensive, rear-engined, four-passenger city car built by the Indian company Tata Motors and is aimed primarily at the Indian domestic market....

624 cc 2008
26 kW / 35 bhp 635 kg / 1,400 lb 41.0 W/kg / 40 lb/hp
Bombardier
Bombardier Transportation
Bombardier Transportation is the rail equipment division of the Canadian firm, Bombardier Inc. Bombardier Transportation is one of the world's largest companies in the rail-equipment manufacturing and servicing industry. Its headquarters are in Berlin, Germany....

JetTrain
JetTrain
The JetTrain is a Canadian experimental high-speed passenger train created by Bombardier Transportation in an attempt to make European-style high-speed service more financially appealing to passenger railways in North America. It uses the same LRC-derived tilting carriages as the Acela Express...

high-speed
High-speed rail
High-speed rail is a type of passenger rail transport that operates significantly faster than the normal speed of rail traffic. Specific definitions by the European Union include for upgraded track and or faster for new track, whilst in the United States, the U.S...

gas turbine-electric locomotive
Gas turbine-electric locomotive
A gas turbine - electric locomotive, or GTEL, is a locomotive that uses a gas turbine to drive an electric generator or alternator. The electric current thus produced is used to power traction motors. This type of locomotive was first experimented with during the Second World War, but reached its...

2000
3,750 kW / 5,029 bhp 90,750 kg / 200,000 lb 41.2 W/kg / 39.8 lb/hp
Suzuki MightyBoy
Suzuki MightyBoy
The Suzuki Mighty Boy was a small ute produced by Suzuki, a member of the Japanese Kei car family. It was classified as a commercial vehicle in Japan so as to benefit from lower taxes for such vehicles, but its utilitarian values were certainly limited.-History:Based on the principles and...

543 cc 1988
23 kW / 31 bhp 550 kg / 1,213 lb 42 W/kg / 39 lb/hp
Mitsubishi i MiEV
Mitsubishi i MiEV
The Mitsubishi i-MiEV is a five-door hatchback electric car produced by Mitsubishi Motors, and is the electric version of the Mitsubishi i. According to the manufacturer, the i-MiEV all-electric range is on the Japanese test cycle...

2009
47 kW / 63 bhp 1,080 kg / 2,381 lb 43.5 W/kg / 37.8 lb/hp
Holden FJ
Holden FJ
The Holden FJ series is a range of motor vehicles which was produced in Australia by General Motors-Holden’s from 1953 to 1957. The FJ was the second model of an "all Australian car" manufactured by Holden and was based upon the established 48-215 series, commonly referred to as the “FX”...

2,160 cc 1953
44.7 kW / 60 bhp 1,021 kg / 2,250 lb 43.8 W/kg / 37.5 lb/hp
Chevrolet Kodiak
Chevrolet Kodiak
Beginning with the 2003 model year, US-market models moved to a new platform with a more spacious cab based on the GM full-size vans. The 4500 and 5500 trucks had the option for Four-wheel drive. These trucks featured solid front axles, on both 4x2 and 4x4, instead of independent front suspension...

/GMC Topkick LYE 6.6 L 2005
246 kW / 330 bhp 5126 kg / 11,300 lb 48 W/kg / 34.2 lb/hp
DOE
United States Department of Energy
The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...

/NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

/0032-28 Chevrolet Celebrity
Chevrolet Celebrity
The Chevrolet Celebrity is a mid-size car produced by the Chevrolet Division of General Motors . The Celebrity was introduced in 1981 for the 1982 model year. The Celebrity was the best-selling car in the United States in 1986...

502 cc ASE
Stirling engine
A Stirling engine is a heat engine operating by cyclic compression and expansion of air or other gas, the working fluid, at different temperature levels such that there is a net conversion of heat energy to mechanical work....

Mod II 1985
62.3 kW / 83.5 bhp 1,297 kg / 2,860 lb 48.0 W/kg / 34.3 lb/hp
Suzuki Alto
Suzuki Alto
The Suzuki Alto is a small car designed by Suzuki. Its selling points include low price and good fuel economy. The model was introduced in 1979 and has been built in many countries worldwide.-1st generation :...

796 cc 2000
35 kW / 46 bhp 720 kg / 1,587 lb 49 W/kg / 35 lb/hp
Land Rover Defender 2.4 L 1990 90 kW / 121 bhp 1,837 kg / 4,050 lb 49 W/kg / 33 lb/hp

##### Common power
Vehicle Power Weight Power-to-weight ratio
Toyota Prius
Toyota Prius
The Toyota Prius is a full hybrid electric mid-size hatchback, formerly a compact sedan developed and manufactured by the Toyota Motor Corporation...

1.8 L 2010 (petrol only)
73 kW / 98 bhp 1,380 kg / 3,042 lb 53 W/kg / 31 lb/hp
Bajaj Platina
Bajaj Platina
Bajaj Platina is a motorcycle built by Bajaj Auto. Currently there are two variants of Platina available with engine capacities of 100 and 125 cc. The 100 cc Platina was launched in April 2006 at an ex-showroom price of Rs 35,000 and crossed sales of 500,000 units within eight months of its launch...

Naked 100 cc 2006
6 kW / 8 bhp 113 kg / 249 lb 53 W/kg / 31 lb/hp
Subaru R2
Subaru R2
For the late 1960s Subaru R-2, please see Subaru R-2The Subaru R2 was announced in Japan on December 8, 2003, and the R2 name was inspired by the Subaru R-2, the kei car model that was produced between 1969 and 1972....

type S 2003
47 kW / 63 bhp 830 kg / 1,830 lb 57 W/kg / 29 lb/hp
Ford Fiesta
Ford Fiesta
The Ford Fiesta is a front wheel drive supermini/subcompact manufactured and marketed by Ford Motor Company and built in Europe, Brazil, Argentina, Mexico, Venezuela, China, India, Thailand and South Africa...

ECOnetic 1.6 L TDCi 5dr 2009
66 kW / 89 bhp 1,155 kg / 2,546 lb 57 W/kg / 29 lb/hp
Volvo C30
Volvo C30
The Volvo C30 is a small family car produced by Volvo Cars. The C30 is a three-door, four-seat hatchback powered by straight-4 and straight-5 engines. The car is a hatchback version of the S40/V50/C70 range, and uses the same Ford C1 platform. It is being marketed as a premium hatchback or a...

1.6D DRIVe S/S
Start-stop system
In automobiles, a start-stop system or stop-start system automatically shuts down and restarts the internal combustion engine to reduce the amount of time the engine spends idling, thereby improving fuel economy and reducing emissions...

3dr Hatch 2010
80 kW / 108 bhp 1,347 kg / 2,970 lb 59.4 W/kg / 27.5 lb/hp
Ford Focus
Ford Focus
The Ford Focus is a compact car manufactured by the Ford Motor Company since 1998. Ford began sales of the Focus to Europe in July 1998 and in North America during 1999 for the 2000 model year....

ECOnetic 1.6 L TDCi 5dr Hatch 2009
81 kW / 108 bhp 1,357 kg / 2,992 lb 59.7 W/kg / 27 lb/hp
Ford Focus
Ford Focus
The Ford Focus is a compact car manufactured by the Ford Motor Company since 1998. Ford began sales of the Focus to Europe in July 1998 and in North America during 1999 for the 2000 model year....

1.8 L Zetec S TDCi 5dr Hatch 2009
84 kW / 113 bhp 1,370 kg / 3,020 lb 61 W/kg / 27 lb/hp
Honda FCX Clarity 4 kg Hydrogen 2008 100 kW / 134 bhp 1,600 kg / 3,528 lb 63 W/kg / 26 lb/hp
Hummer H1
Hummer H1
The Hummer H1 is a civilian off-road vehicle based on the M998 Humvee, which was created by AM General. The vehicle was produced from 1992 through 2006, and was the first of what became the Hummer line...

6.6 L V8 2006
224 kW / 300 bhp 3,559 kg / 7,847 lb 63 W/kg / 26 lb/hp
Audi A2
Audi A2
The Audi A2 is a Compact MPV styled five-door four- or five-seat hatchback designed supermini, produced by the German automaker Audi AG from November 1999 to 2005...

1.4 L TDI 90 type S 2003
66 kW / 89 bhp 1,030 kg / 2,270 lb 64 W/kg / 25 lb/hp
Opel
Opel
Adam Opel AG, generally shortened to Opel, is a German automobile company founded by Adam Opel in 1862. Opel has been building automobiles since 1899, and became an Aktiengesellschaft in 1929...

/Vauxhall
Vauxhall
-Demography:Many Vauxhall residents live in social housing. There are several gentrified areas, and areas of terraced townhouses on streets such as Fentiman Road and Heyford Avenue have higher property values in the private market, however by far the most common type of housing stock within...

/Holden
Holden
GM Holden Ltd is an automaker that operates in Australia, based in Port Melbourne, Victoria. The company was founded in 1856 as a saddlery manufacturer. In 1908 it moved into the automotive field, before becoming a subsidiary of the U.S.-based General Motors in 1931...

/Chevrolet
Chevrolet
Chevrolet , also known as Chevy , is a brand of vehicle produced by General Motors Company . Founded by Louis Chevrolet and ousted GM founder William C. Durant on November 3, 1911, General Motors acquired Chevrolet in 1918...

Astra
Opel Astra
The Opel Astra is a small family car engineered and manufactured by the German automaker Opel since 1991.It is branded as Vauxhall Astra in the United Kingdom, the Buick Excelle XT in China and the Chevrolet Astra/Vectra in Latin America...

1.7 L CTDi 125 2010
92 kW / 123 bhp 1,393 kg / 3,071 lb 66 W∕kg / 24.9 lb∕hp
Mini (new)
MINI (BMW)
Mini is a British automotive marque owned by BMW which specialises in small cars.Mini originated as a specific vehicle, a small car originally known as the Morris Mini-Minor and the Austin Seven, launched by the British Motor Corporation in 1959, and developed into a brand encompassing a range of...

Cooper 1.6D 2007
81 kW / 108 bhp 1,185 kg / 2,612 lb 68 W/kg / 24 lb/hp
Toyota Prius
Toyota Prius
The Toyota Prius is a full hybrid electric mid-size hatchback, formerly a compact sedan developed and manufactured by the Toyota Motor Corporation...

1.8 L 2010 (electric boost)
100 kW / 134 bhp 1,380 kg / 3,042 lb 72 W/kg / 23 lb/hp
Ford Focus
Ford Focus
The Ford Focus is a compact car manufactured by the Ford Motor Company since 1998. Ford began sales of the Focus to Europe in July 1998 and in North America during 1999 for the 2000 model year....

2.0 L Zetec S TDCi 5dr Hatch 2009
100 kW / 134 bhp 1,370 kg / 3,020 lb 73 W/kg / 23 lb/hp
Toyota Venza
Toyota Venza
The Toyota Venza is a mid-size crossover SUV produced by Japanese automaker Toyota and unveiled at the 2008 North American International Auto Show in Detroit...

I4 2.7 L FWD
Front-wheel drive
Front-wheel drive is a form of engine/transmission layout used in motor vehicles, where the engine drives the front wheels only. Most modern front-wheel drive vehicles feature a transverse engine, rather than the conventional longitudinal engine arrangement generally found in rear-wheel drive and...

2009
136 kW / 182 bhp 1,706 kg / 3,760 lb 80 W/kg / 20.7 lb/hp
Ford Focus
Ford Focus
The Ford Focus is a compact car manufactured by the Ford Motor Company since 1998. Ford began sales of the Focus to Europe in July 1998 and in North America during 1999 for the 2000 model year....

2.0 L Zetec S 5dr Hatch 2009
107 kW / 143 bhp 1,327 kg / 2,926 lb 81 W/kg / 20 lb/hp
Fiat Grande Punto
Fiat Grande Punto
The Fiat Grande Punto is a car manufactured by the Italian automaker Fiat. It was unveiled on May 5, 2005 and replaced by the Punto Evo in 2010. In September 2011 Fiat unveil the Punto model year 2012, the new version will replaced the Grande Punto and the Punto Evo...

1.6 L Multijet 120 2005
88 kW / 118 bhp 1,075 kg / 2,370 lb 82 W/kg / 20 lb/hp
Mini (classic)
Mini
The Mini is a small car that was made by the British Motor Corporation and its successors from 1959 until 2000. The original is considered a British icon of the 1960s, and its space-saving front-wheel-drive layout influenced a generation of car-makers...

1275GT 1969
57 kW / 76 bhp 686 kg / 1,512 lb 83 W/kg / 20 lb/hp
Opel
Opel
Adam Opel AG, generally shortened to Opel, is a German automobile company founded by Adam Opel in 1862. Opel has been building automobiles since 1899, and became an Aktiengesellschaft in 1929...

/Vauxhall
Vauxhall
-Demography:Many Vauxhall residents live in social housing. There are several gentrified areas, and areas of terraced townhouses on streets such as Fentiman Road and Heyford Avenue have higher property values in the private market, however by far the most common type of housing stock within...

/Holden
Holden
GM Holden Ltd is an automaker that operates in Australia, based in Port Melbourne, Victoria. The company was founded in 1856 as a saddlery manufacturer. In 1908 it moved into the automotive field, before becoming a subsidiary of the U.S.-based General Motors in 1931...

/Chevrolet
Chevrolet
Chevrolet , also known as Chevy , is a brand of vehicle produced by General Motors Company . Founded by Louis Chevrolet and ousted GM founder William C. Durant on November 3, 1911, General Motors acquired Chevrolet in 1918...

Astra
Opel Astra
The Opel Astra is a small family car engineered and manufactured by the German automaker Opel since 1991.It is branded as Vauxhall Astra in the United Kingdom, the Buick Excelle XT in China and the Chevrolet Astra/Vectra in Latin America...

2.0 L CTDi 160 2010
118 kW / 158 bhp 1,393 kg / 3,071 lb 85 W∕kg / 19.4 lb∕hp
Subaru Legacy/Liberty
Subaru Legacy
The Subaru Legacy is a mid-size car built by the Japanese company Fuji Heavy Industries, and manufactured by its division Subaru since 1989, and is available as a sedan or wagon. Part of the original design goals for the Legacy model was to provide Subaru a vehicle in which they could compete in...

2.0R 2005
121 kW / 162 bhp 1,370 kg / 3,020 lb 88 W/kg / 19 lb/hp
Subaru Outback
Subaru Outback
The Subaru Outback is a station wagon manufactured by Fuji Heavy Industries since 1995. Its original concept originated with Subaru of America, which was suffering from slumping sales in the mid-1990s partly due to a lack of an entry in the then-burgeoning sport utility vehicle market...

2.5i 2008
130.5 kW / 175 bhp 1,430 kg / 3,153 lb 91 W/kg / 18 lb/hp
Smart Fortwo
Smart Fortwo
The Smart Fortwo is a rear-engined two-seater city car manufactured by Smart GmbH, introduced at the 1998 Paris Motor Show as the Smart City Coupé, and currently in its second generation...

1.0 L Brabus 2009
72 kW / 97 bhp 780 kg / 1,720 lb 92 W/kg / 18 lb/hp
Ford Focus 2.0 auto 2007 104.4 kW / 140 bhp 1,198 kg / 2,641 lb 87.1 W/kg / 19 lb/hp
Toyota Venza
Toyota Venza
The Toyota Venza is a mid-size crossover SUV produced by Japanese automaker Toyota and unveiled at the 2008 North American International Auto Show in Detroit...

V6 3.5 L AWD 2009
200 kW / 268 bhp 1,835 kg / 4,045 lb 109 W/kg / 15 lb/hp
Toyota Venza
Toyota Venza
The Toyota Venza is a mid-size crossover SUV produced by Japanese automaker Toyota and unveiled at the 2008 North American International Auto Show in Detroit...

I4 2.7 L FWD
Front-wheel drive
Front-wheel drive is a form of engine/transmission layout used in motor vehicles, where the engine drives the front wheels only. Most modern front-wheel drive vehicles feature a transverse engine, rather than the conventional longitudinal engine arrangement generally found in rear-wheel drive and...

2009 with Lotus mass reduction
136 kW / 182 bhp 1,210 kg / 2,667 lb 112.2 W/kg / 14.7 lb/hp
Toyota Hilux
Toyota Hilux
The Toyota Hilux is a series of compact pickup trucks produced and marketed by the Toyota Motor Corporation. Most countries used the Hilux name for the entire life of the series but in North America, the Hilux name was retired in 1976 in favor of Truck, Pickup Truck, or Compact Truck...

V6 DOHC 4 L 4×2 Single Cab Pickup
Pickup truck
A pickup truck is a light motor vehicle with an open-top rear cargo area .-Definition:...

ute
Coupé utility
The coupé utility automobile body style, also known colloquially as the ute in Australia and New Zealand, combines a two-door "coupé" cabin with an integral cargo bed behind the cabin—using a light-duty passenger vehicle-derived platform....

2009
175 kW / 235 bhp 1,555 kg / 3,428 lb 112.5 W/kg / 14.6 lb/hp
Toyota Venza
Toyota Venza
The Toyota Venza is a mid-size crossover SUV produced by Japanese automaker Toyota and unveiled at the 2008 North American International Auto Show in Detroit...

V6 3.5 L FWD
Front-wheel drive
Front-wheel drive is a form of engine/transmission layout used in motor vehicles, where the engine drives the front wheels only. Most modern front-wheel drive vehicles feature a transverse engine, rather than the conventional longitudinal engine arrangement generally found in rear-wheel drive and...

2009
200 kW / 268 bhp 1,755 kg / 3,870 lb 114 W/kg / 14.4 lb/hp

##### Performance luxury, roadsters and mild sports

Some utility and practical vehicles are designed for, as BMW
BMW
Bayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...

would say, sheer driving pleasure. Increased engine performance is a consideration, but also other features associated with luxury vehicles. Longitudinal engine
Longitudinal engine
In automotive engineering, a longitudinal engine is an internal combustion engine in which the crankshaft is oriented along the long axis of the vehicle, front to back....

s are common. Bodies vary from hot hatch
Hot hatch
Hot hatch was originally an informal automotive industry term, shortened from hot hatchback, initially coined by the British motoring press in 1984, for a high-performance derivative of a car body style consisting of a three- or five-door hatchback automobile.Vehicles of this class are based on...

es, sedans (saloons), coupé
Coupé
A coupé or coupe is a closed car body style , the precise definition of which varies from manufacturer to manufacturer, and over time...

A roadster is a two-seat open car with emphasis on sporty handling and without a fixed roof or side weather protection. Strictly speaking a roadster with wind-up windows is a convertible but as true roadsters are no longer made the distinction is now irrelevant...

s. Mid-range dual-sport and cruiser
Cruiser (motorcycle)
Cruiser is the term for motorcycles that mimic the design style of American machines from the 1930s to the early 1960s, including those made by Harley-Davidson, Indian, Excelsior and Henderson. The market for models evocative of the early cruisers has grown to embrace 60 percent of the U.S...

motorcycles tend to have similar power-to-weight ratios.
Vehicle Power Weight Power-to-weight ratio
Mini (new)
MINI (BMW)
Mini is a British automotive marque owned by BMW which specialises in small cars.Mini originated as a specific vehicle, a small car originally known as the Morris Mini-Minor and the Austin Seven, launched by the British Motor Corporation in 1959, and developed into a brand encompassing a range of...

Cooper 1.6T S JCW 2008
155 kW / 208 bhp 1205 kg / 2657 lb 129 W/kg / 13 lb/hp
Mazda RX-8
Mazda RX-8
The Mazda RX-8 is a sports car manufactured by Mazda Motor Corporation. It first appeared in 2001 at the North American International Auto Show. It is the successor to the RX-7 and, like its predecessors in the RX range, it is powered by a Wankel engine. The RX-8 began North American sales in the...

1.3 L Wankel
Wankel engine
The Wankel engine is a type of internal combustion engine using an eccentric rotary design to convert pressure into a rotating motion instead of using reciprocating pistons. Its four-stroke cycle takes place in a space between the inside of an oval-like epitrochoid-shaped housing and a rotor that...

2003
173 kW / 232 bhp 1309 kg / 2888 lb 141 W/kg / 12 lb/hp
Holden Statesman/Caprice / Buick Park Avenue / Daewoo Veritas 6 L V8 2007 270 kW / 362 bhp 1891 kg / 4170 lb 143 W/kg / 12 lb/hp
Kawasaki KLR650
Kawasaki KLR650
The Kawasaki KLR650 is a dual-sport motorcycle intended for use on both paved and unpaved roads. It has been a long-standing model in Kawasaki's lineup, having been introduced in 1987 and remaining almost unchanged through the 2007 model. The 2008 model was the first significant redesign of the...

Gasoline DualSport 650 cc
26 kW / 35 bhp 182 kg / 401 lb 143 W/kg / 11 lb/hp
NATO HTC M1030M1 Diesel/Jet fuel
JP-8
JP-8, or JP8 is a jet fuel, specified and used widely by the US military. It is specified by MIL-DTL-83133 and British Defence Standard 91-87, and similar to commercial aviation's Jet-A....

DualSport 670 cc
26 kW / 35 bhp 182 kg / 401 lb 143 W/kg / 11 lb/hp
Harley-Davidson FLSTF Softail Fat Boy Cruiser
Cruiser (motorcycle)
Cruiser is the term for motorcycles that mimic the design style of American machines from the 1930s to the early 1960s, including those made by Harley-Davidson, Indian, Excelsior and Henderson. The market for models evocative of the early cruisers has grown to embrace 60 percent of the U.S...

1,584 cc 2009
47 kW / 63 bhp 324 kg / 714 lb 145 W/kg / 11.3 lb/hp
BMW 7 Series
BMW 7 Series
The BMW 7 Series is a line of full-size luxury vehicles produced by the German automaker BMW. Introduced in 1977, it is BMW's flagship car and is only available as a sedan or extended-length limousine...

760Li 6 L V12 2006
327 kW / 439 bhp 2250 kg / 4960 lb 145 W/kg / 11 lb/hp
Subaru Impreza WRX STi
Subaru Impreza WRX STI
The Subaru Impreza WRX STI, has the highest trim in the Subaru Impreza compact car line, produced by Japanese automaker Subaru.In the late 1980s, Subaru created the Subaru Tecnica International division to coordinate development for the FIA World Rally Championship and other motorsports activities...

2.0 L 2008
227 kW / 304 bhp 1530 kg / 3373 lb 148 W/kg / 11 lb/hp
Honda S2000
Honda S2000
The Honda S2000 is a roadster that was manufactured by the Japanese automaker Honda Motor Company. It was launched in April 1999 and was created to celebrate the company's 50th anniversary. The car was first shown as a concept at the Tokyo Motor Show in 1995, following which it was launched in...

A roadster is a two-seat open car with emphasis on sporty handling and without a fixed roof or side weather protection. Strictly speaking a roadster with wind-up windows is a convertible but as true roadsters are no longer made the distinction is now irrelevant...

1999
183.88 kW / 240 bhp 1250 kg / 2723 lb 150 W/kg / 11 lb/hp
Ford Mustang
Ford Mustang
The Ford Mustang is an automobile manufactured by the Ford Motor Company. It was initially based on the second generation North American Ford Falcon, a compact car. Introduced early on April 17, 1964, as a "1964½" model, the 1965 Mustang was the automaker's most successful launch since the Model A...

2005 4.0 L SOHC V6
231 kW / 310 bhp 1497 kg / 3300 lb 154 W/kg / 10.65 lb/hp
GMH HSV Clubsport / GMV VXR8 / GMC CSV CR8 / Pontiac G8
HSV Clubsport
The HSV Clubsport is a full-size car which has been produced by Holden Special Vehicles in Australia since 1990. All models have been based on contemporary Holden Commodore models...

6 L V8 2006
317 kW / 425 bhp 1831 kg / 4037 lb 173 W/kg / 9.5 lb/hp
The Tesla Roadster is a battery electric vehicle sports car produced by the electric car firm Tesla Motors in California. The Roadster was the first highway-capable all-electric vehicle in serial production available in the United States. Since 2008 Tesla has sold 2,024 Roadsters in 30 countries...

2011
215 kW / 288 bhp 1235 kg / 2723 lb 174 W/kg / 9.5 lb/hp

#### Sports vehicles and aircraft

Power-to-weight ratio is an important vehicle characteristic that affects the acceleration and handling - and therefore the driving enjoyment - of any sports vehicle.
Aircraft also depend on high power-to-weight ratio to achieve sufficient lift
Lift (force)
A fluid flowing past the surface of a body exerts a surface force on it. Lift is the component of this force that is perpendicular to the oncoming flow direction. It contrasts with the drag force, which is the component of the surface force parallel to the flow direction...

.
Vehicle Power Weight Power-to-weight ratio
Lotus Elise
Lotus Elise
The 1996 Lotus Elise weighed . Because of its relatively low weight, it was able to accelerate 0- in 5.8 seconds despite its relatively low power output of...

SC 2008
163 kW / 218 bhp 910 kg / 2006 lb 179 W/kg / 9 lb/hp
Ferrari Testarossa
Ferrari Testarossa
The Ferrari Testarossa is a 12-cylinder mid-engine sports car manufactured by Ferrari, which went into production in 1984 as the successor to the Ferrari Berlinetta Boxer...

1984
291 kW / 390 bhp 1506 kg / 3320 lb 193 W/kg / 9 lb/hp
Artega GT
Artega GT
The Artega GT is a mid-engined, rear wheel drive 2-seat sports car produced by German manufacturer Artega. The GT is currently Artega's first and only model for sale.-Overview:...

220 kW / 300 bhp 1100 kg / 2425 lb 200 W/kg / 8 lb/hp
Lotus Exige
Lotus Exige
The Lotus Exige is a two-door, two-seat sports car made by Lotus Cars. It is essentially a coupé version of the Lotus Elise, a mid-engined roadster in production since 1996....

GT3 2006
202.1 kW / 271 bhp 980 kg / 2160 lb 206 W/kg / 8 lb/hp
Bombardier
Bombardier Aerospace
Bombardier Aerospace is a division of Bombardier Inc. and is the third-largest airplane manufacturer in the world. It is headquartered in Dorval, Quebec, Canada.- History :...

Dash 8 Q400 turboprop
Turboprop
A turboprop engine is a type of turbine engine which drives an aircraft propeller using a reduction gear.The gas turbine is designed specifically for this application, with almost all of its output being used to drive the propeller...

airliner
Airliner
An airliner is a large fixed-wing aircraft for transporting passengers and cargo. Such aircraft are operated by airlines. Although the definition of an airliner can vary from country to country, an airliner is typically defined as an aircraft intended for carrying multiple passengers in commercial...

3,781 kW / 5,071 bhp 17,185 kg / 37,888 lb 220 W/kg / 7.5 lb/hp
Chevrolet Corvette C6
Chevrolet Corvette C6
The Chevrolet Corvette is a sports car produced by the Chevrolet division of General Motors introduced for the 2005 model year. The current generation Corvette is the first with exposed headlamps since the 1962 model...

321 kW / 430 bhp 1441 kg / 3177 lb 223 W/kg / 7 lb/hp
Suzuki V-Strom 650 V-twin DualSport 650 cc 50 kW / 67 bhp 194 kg / 427 lb 258 W/kg / 6.4 lb/hp
Chevrolet Corvette C6
Chevrolet Corvette C6
The Chevrolet Corvette is a sports car produced by the Chevrolet division of General Motors introduced for the 2005 model year. The current generation Corvette is the first with exposed headlamps since the 1962 model...

Z06
376 kW / 505 bhp 1421 kg / 3133 lb 265 W/kg / 6 lb/hp
Porsche 911 GT2
Porsche 997
The Porsche Type 997 , also simply called the 997 is the current version of the 911 family sports car built by German manufacturer Porsche in Stuttgart-Zuffenhausen...

2007
390 kW / 523 bhp 1440 kg / 3200 lb 271 W/kg / 6.1 lb/hp
Lamborghini Murciélago
Lamborghini Murciélago
The Lamborghini Murciélago is a two-door, two-seat sports car produced by Italian automaker Lamborghini between 2001 and 2010. Successor to the Diablo and flagship of the automaker's lineup, the Murciélago was introduced as a coupé in 2001. The automaker's first new design in eleven years, the car...

LP 670-4 SV 2009
493 kW / 661 bhp 1550 kg / 3417 lb 318 W/kg / 5.1 lb/hp
McLaren F1
McLaren F1
The McLaren F1 is a supercar designed and manufactured by McLaren Automotive. Originally a concept conceived by Gordon Murray, he convinced Ron Dennis to back the project and engaged Peter Stevens to design the exterior of the car...

GT 1997
467.6 kW / 627 bhp 1220 kg / 2690 lb 403 W/kg / 4 lb/hp
Supermarine Spitfire
Supermarine Spitfire
The Supermarine Spitfire is a British single-seat fighter aircraft that was used by the Royal Air Force and many other Allied countries throughout the Second World War. The Spitfire continued to be used as a front line fighter and in secondary roles into the 1950s...

Fighter aircraft
Fighter aircraft
A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...

1936
1,096 kW / 1,470 bhp 2,309 kg / 5,090 lb 475 W/kg / 3.46 lb/hp
Messerschmitt Bf 109
Messerschmitt Bf 109
The Messerschmitt Bf 109, often called Me 109, was a German World War II fighter aircraft designed by Willy Messerschmitt and Robert Lusser during the early to mid 1930s...

Fighter aircraft
Fighter aircraft
A fighter aircraft is a military aircraft designed primarily for air-to-air combat with other aircraft, as opposed to a bomber, which is designed primarily to attack ground targets...

1935
1,085 kW / 1,455 bhp 2,247 kg / 4,954 lb 483 W/kg / 3.40 lb/hp
Thunderbolt
Thunderbolt (car)
Thunderbold is a British Land Speed Record holder of the 1930s, driven by Captain George E.T. Eyston- Records held :Between 1937 and 1939, the competition for the Land Speed Record was between two Englishmen: Captain Eyston and John Cobb. Thunderbolt's first record was set at on 19 November 1937...

Land speed record
Land speed record
The land speed record is the highest speed achieved by a wheeled vehicle on land. There is no single body for validation and regulation; in practice the Category C flying start regulations are used, officiated by regional or national organizations under the auspices of the Fédération...

car
3504 kW / 4700 bhp 7 t / 15432 lb 500 W/kg / 3.28 lb/hp
Ferrari FXX
Ferrari FXX
The Ferrari FXX is a high performance race car built by automobile manufacturer Ferrari in Maranello, Italy. The FXX is based on the street-legal Enzo. Production of the FXX began in 2005.- Overview :...

2005
597 kW / 801 bhp 1155 kg / 2546 lb 517 W/kg / 3.2 lb/hp
Polaris Industries
Polaris Industries
Polaris Industries is a manufacturer of snowmobiles, ATV, and neighborhood electric vehicles. Polaris is based in Medina, Minnesota, USA. The company also manufactures motorcycles through its Victory Motorcycles subsidiary and through the Indian Motorcycle subsidiary which it purchased in April...

Assault Snowmobile 2009
115 kW / 154 bhp 221 kg / 487 lb 523 W/kg / 3.16 lb/hp
Ultima GTR
Ultima GTR
The Ultima GTR is a sports car manufactured by Ultima Sports Ltd of Hinckley, Leicestershire, England, and described by commentators as a supercar. The car is available both in kit form and as a "turnkey" vehicle. The design is mid engined, rear wheel drive layout, with a tubular steel space...

720 2006
536.9 kW / 720 bhp 920 kg / 2183 lb 583 W/kg / 3 lb/hp
Honda CBR1000RR
Honda CBR1000RR
The CBR1000RR, also known as the Fireblade, is a liquid-cooled inline four-cylinder sport bike that was introduced by Honda in 2004 to replace the CBR954RR.-Racing roots:...

2009
133 kW / 178 bhp 199 kg / 439 lb 668 W/kg / 2.5 lb/hp
Ariel Atom
Ariel Atom
The Ariel Atom is a high performance sports car made by the Ariel Motor Company based in Somerset, England and under licence in North America by TMI Autotech, Inc. at Virginia International Raceway in Alton, Virginia....

500 V8 2011
372 kW / 500 bhp 550 kg / 1212 lb 676.3 W/kg / 2.45 lb/hp
KillaCycle
Killacycle
The KillaCycle is an electrically powered motorcycle purpose-built for drag racing. It was built and is managed by a small motorworks team owned and run by Bill Dubé...

Drag racing
Drag racing
Drag racing is a competition in which specially prepared automobiles or motorcycles compete two at a time to be the first to cross a set finish line, from a standing start, in a straight line, over a measured distance, most commonly a ¼-mile straight track....

electric motorcycle
Electric motorcycles and scooters
Electric motorcycles and scooters are vehicles with two or three wheels that use electric motors to attain locomotion. Electric motorcycles, as distinguished from scooters, do not have a step-through frame....

260 kW / 350 bhp 281 kg / 619 lb 925 W/kg / 1.77 lb/hp
MTT Turbine Superbike
MTT Turbine SUPERBIKE
The MTT Turbine Superbike The MTT Turbine Superbike The MTT Turbine Superbike (often styled SUPERBIKE, also known as the Y2K Turbine SUPERBIKE, is the world's second wheel-driven motorcycle powered by a turbine engine, created by Ted McIntyre of Marine Turbine Technologies Inc....

2008
213.3 kW / 286 bhp 227 kg / 500 lb 940 W/kg / 1.75 lb/hp
Vyrus 987 C3 4V V supercharged motorcycle 2010 157.3 kW / 211 bhp 158 kg / 348.3 lb 996 W/kg / 1.65 lb/hp
BMW
BMW
Bayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...

Williams FW27
Williams FW27
The Williams FW27 was the Formula One car which the Williams team used during the 2005 Formula One season. While Williams was able to compete and take a couple of victories home in recent years, the FW27 proved not to be up to the same performance levels as some of the other teams' cars...

Formula One
Formula One
Formula One, also known as Formula 1 or F1 and referred to officially as the FIA Formula One World Championship, is the highest class of single seater auto racing sanctioned by the Fédération Internationale de l'Automobile . The "formula" designation in the name refers to a set of rules with which...

2005
690 kW / 925 bhp 600 kg / 1323 lb 1150 W/kg / 1.43 lb/hp
Honda RC211V
Honda RC211V
The Honda RC211V was developed in 2001 by HRC to replace the Honda NSR500 because regulations for the World Championship motorcycle road racing class were changed drastically for the 2002 season. Two-stroke engines were as before limited to and 4 cylinders, but four-stroke engines were allowed...

MotoGP 2004-6
176.73 kW / 237 bhp 148 kg / 326 lb 1194 W/kg / 1.37 lb/hp
John Force Racing
John Force Racing
John Force Racing is an NHRA drag racing team. In over 30 years of competition, John Force Racing has won 17 Funny Car championships. The current line-up of drivers includes John Force, Mike Neff, and Robert Hight. John Force Racing has had Castrol as their main sponsor for more than 30 years...

Funny Car
Funny Car
Funny Car is a drag racing car class. In the United States, other "professional" classes are Top Fuel, Pro Stock, and Pro Stock Motorcycle. Funny cars have forward-mounted engines and carbon fiber automotive bodies over the chassis, giving them an appearance vaguely approximating manufacturers'...

NHRA Drag Racing
Drag racing
Drag racing is a competition in which specially prepared automobiles or motorcycles compete two at a time to be the first to cross a set finish line, from a standing start, in a straight line, over a measured distance, most commonly a ¼-mile straight track....

2008
5,963.60 kW / 8,000 bhp 1043 kg / 2,300 lb 5717 W/kg / 0.30 lb/hp

##### Supersonic vehicles

Some sports and aerospace
Aerospace
Aerospace comprises the atmosphere of Earth and surrounding space. Typically the term is used to refer to the industry that researches, designs, manufactures, operates, and maintains vehicles moving through air and space...

vehicles are capable of exceeding the speed of sound. Vehicles in this class must account for transonic
Transonic
Transonic speed is an aeronautics term referring to the condition of flight in which a range of velocities of airflow exist surrounding and flowing past an air vehicle or an airfoil that are concurrently below, at, and above the speed of sound in the range of Mach 0.8 to 1.2, i.e. 600–900 mph...

wave drag
Wave drag
In aeronautics, wave drag is a component of the drag on aircraft, blade tips and projectiles moving at transonic and supersonic speeds, due to the presence of shock waves. Wave drag is independent of viscous effects.- Overview :...

, shock wave
Shock wave
A shock wave is a type of propagating disturbance. Like an ordinary wave, it carries energy and can propagate through a medium or in some cases in the absence of a material medium, through a field such as the electromagnetic field...

s and aerodynamic heating
Aerodynamic heating
Aerodynamic heating is the heating of a solid body produced by the passage of fluid over a body such as a meteor, missile, or airplane. It is a form of forced convection in that the flow field is created by forces beyond those associated with the thermal processes...

. Turbojet, turbofan
Turbofan
The turbofan is a type of airbreathing jet engine that is widely used for aircraft propulsion. A turbofan combines two types of engines, the turbo portion which is a conventional gas turbine engine, and the fan, a propeller-like ducted fan...

, ramjet
Ramjet
A ramjet, sometimes referred to as a stovepipe jet, or an athodyd, is a form of airbreathing jet engine using the engine's forward motion to compress incoming air, without a rotary compressor. Ramjets cannot produce thrust at zero airspeed and thus cannot move an aircraft from a standstill...

, afterburner
AfterBurner
The AfterBurner is a lighting solution for the Game Boy Advance system that was created by Triton-Labs.Originally, portablemonopoly.net was a website created to petition Nintendo to put some kind of light in their Game Boy Advance system...

and rocket
Rocket
A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...

propulsion is common. Note that with rockets and air breathing jet engines, vehicle power is proportional to vehicle speed
Oberth effect
In astronautics, the Oberth effect is where the use of a rocket engine when travelling at high speed generates much more useful energy than one at low speed...

, since rockets(and too a lesser extent air breathing jet engines) give a thrust that is completely independent of speed, this means that there is no upper limit to any particular rocket's power-to-weight ratio provided it has been given sufficient initial speed.
Vehicle Power Weight Power-to-weight ratio
Space Shuttle Endeavour
Space Shuttle Endeavour
Space Shuttle Endeavour is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States. Endeavour was the fifth and final spaceworthy NASA space shuttle to be built, constructed as a replacement for Challenger...

(OV
Orbiter Vehicle Designation
Each NASA space shuttle designation is composed of a prefix and suffix separated by a dash. The prefix for operational shuttles is OV, for Orbiter Vehicle.The suffix is composed of two parts: the series and the vehicle number.Series:...

-105)
190 MW / 255,000 bhp 78 t / 172,000 lb 2,437 W/kg / 0.7 lb/hp
Aérospatiale
Aérospatiale
Aérospatiale was a French aerospace manufacturer that built both civilian and military aircraft, rockets and satellites. It was originally known as Société Nationale Industrielle Aérospatiale...

/BAC
British Aircraft Corporation
The British Aircraft Corporation was a British aircraft manufacturer formed from the government-pressured merger of English Electric Aviation Ltd., Vickers-Armstrongs , the Bristol Aeroplane Company and Hunting Aircraft in 1960. Bristol, English Electric and Vickers became "parents" of BAC with...

Concorde
Concorde
Aérospatiale-BAC Concorde was a turbojet-powered supersonic passenger airliner, a supersonic transport . It was a product of an Anglo-French government treaty, combining the manufacturing efforts of Aérospatiale and the British Aircraft Corporation...

1969 at Mach 2.02 supercruise full thrust
330 MW / 443,143 bhp 78.7 t / 173,500 lb 4,199 W/kg / 0.39 lb/hp
Thrust Super Sonic Car
ThrustSSC
ThrustSSC, also spelt Thrust SSC by secondary sources, is a British jet-propelled car developed by Richard Noble, Glynne Bowsher, Ron Ayers and Jeremy Bliss....

82 MW / 110,000 bhp 10.5 t / 23,149 lb 7,812 W/kg / 0.21 lb/hp
F-35 Lightning II
F-35 Lightning II
The Lockheed Martin F-35 Lightning II is a family of single-seat, single-engine, fifth generation multirole fighters under development to perform ground attack, reconnaissance, and air defense missions with stealth capability...

Multirole combat aircraft
Multirole combat aircraft
A multirole combat aircraft is an aircraft designed to act in at least two different roles in combat. The primary role is usually a fighter—hence, it is as often called a multirole fighter—while the secondary role is usually air-to-surface attack. More roles are added, such as air reconnaissance,...

2006 at Mach 1.67 full thrust
110 MW / 146,922 bhp 13,300 kg / 29,300 lb 8,238 W/kg / 0.20 lb/hp
Sukhoi Su-35BM Multirole combat aircraft
Multirole combat aircraft
A multirole combat aircraft is an aircraft designed to act in at least two different roles in combat. The primary role is usually a fighter—hence, it is as often called a multirole fighter—while the secondary role is usually air-to-surface attack. More roles are added, such as air reconnaissance,...

2008 at Mach 2.25 full thrust
188.5 MW / 252,842 bhp 18,400 kg / 40,500 lb 10,247 W/kg / 0.16 lb/hp
Lockheed
Lockheed Corporation
The Lockheed Corporation was an American aerospace company. Lockheed was founded in 1912 and later merged with Martin Marietta to form Lockheed Martin in 1995.-Origins:...

SR-71 Blackbird Surveillance aircraft
Surveillance aircraft
A surveillance aircraft is an aircraft used for surveillance — collecting information over time. They are operated by military forces and other government agencies in roles such as intelligence gathering, battlefield surveillance, airspace surveillance, observation , border patrol and fishery...

1966 at Mach 3.2, 290 kN thrust
318.3 MW / 426,853 bhp 30,600 kg / 67,461 lb 10,402 W/kg / 0.16 lb/hp
Sukhoi T-50 Stealth
Stealth aircraft
Stealth aircraft are aircraft that use stealth technology to avoid detection by employing a combination of features to interfere with radar as well as reduce visibility in the infrared, visual, audio, and radio frequency spectrum. Development of stealth technology likely began in Germany during...

multirole fighter aircraft 2010 at Mach 2, 294 kN thrust
201 MW / 270,620 bhp 18,500 kg / 40,786 lb 10,908 W/kg / 0.15 lb/hp
F-22 Raptor
F-22 Raptor
The Lockheed Martin/Boeing F-22 Raptor is a single-seat, twin-engine fifth-generation supermaneuverable fighter aircraft that uses stealth technology. It was designed primarily as an air superiority fighter, but has additional capabilities that include ground attack, electronic warfare, and signals...

Air superiority fighter
Air superiority fighter
An air superiority fighter is a type of fighter aircraft intended to gain air superiority in a war, by entering and seizing control of enemy airspace. Air superiority fighters are designed to effectively engage enemy fighters, more than other types of aircraft...

aircraft 1990 at Mach 2.25, 312 kN thrust
241 MW / 323,088 bhp 19,700 kg / 43,430 lb 12,230 W/kg / 0.13 lb/hp
Rockwell
Rockwell International
Rockwell International was a major American manufacturing conglomerate in the latter half of the 20th century, involved in aircraft, the space industry, both defense-oriented and commercial electronics, automotive and truck components, printing presses, valves and meters, and industrial automation....

X-30
Rockwell X-30

scramjet
Scramjet
A scramjet is a variant of a ramjet airbreathing jet engine in which combustion takes place in supersonic airflow...

SSTO
Single-stage-to-orbit
A single-stage-to-orbit vehicle reaches orbit from the surface of a body without jettisoning hardware, expending only propellants and fluids. The term usually, but not exclusively, refers to reusable vehicles....

spaceplane
Spaceplane
A spaceplane is a vehicle that operates as an aircraft in Earth's atmosphere, as well as a spacecraft when it is in space. It combines features of an aircraft and a spacecraft, which can be thought of as an aircraft that can endure and maneuver in the vacuum of space or likewise a spacecraft that...

1986 at Mach 30, 1.4 MN thrust (proposed)
14 GW / 19,300,000 bhp 136 t / 300,000 lb 105,740 W∕kg / 0.016 lb/hp
Space Shuttle Endeavour
Space Shuttle Endeavour
Space Shuttle Endeavour is one of the retired orbiters of the Space Shuttle program of NASA, the space agency of the United States. Endeavour was the fifth and final spaceworthy NASA space shuttle to be built, constructed as a replacement for Challenger...

(OV
Orbiter Vehicle Designation
Each NASA space shuttle designation is composed of a prefix and suffix separated by a dash. The prefix for operational shuttles is OV, for Orbiter Vehicle.The suffix is composed of two parts: the series and the vehicle number.Series:...

-105) with SLWT and 2 SRB
Space Shuttle Solid Rocket Booster
The Space Shuttle Solid Rocket Boosters were the pair of large solid rockets used by the United States' NASA Space Shuttle during the first two minutes of powered flight. Together they provided about 83% of liftoff thrust for the Space Shuttle. They were located on either side of the rusty or...

s
33 GW / 44,000,000 bhp 280 t / 616,500 lb 118,000 W/kg / 0.014 lb/hp

• Thrust-to-weight ratio
Thrust-to-weight ratio
Thrust-to-weight ratio is a ratio of thrust to weight of a rocket, jet engine, propeller engine, or a vehicle propelled by such an engine. It is a dimensionless quantity and is an indicator of the performance of the engine or vehicle....

• Vehicle metrics
Vehicle metrics
There are a broad range of metrics that denote the relative capabilities of various vehicles. Most of them apply to all vehicles while others are type-specific....

• Energy density
Energy density
Energy density is a term used for the amount of energy stored in a given system or region of space per unit volume. Often only the useful or extractable energy is quantified, which is to say that chemically inaccessible energy such as rest mass energy is ignored...

• Propulsive efficiency
Propulsive efficiency
In aircraft and rocket design, overall propulsive efficiency \eta is the efficiency, in percent, with which the energy contained in a vehicle's propellant is converted into useful energy, to replace losses due to air drag, gravity, and acceleration. It can also be stated as the proportion of the...