PJM Interconnection
Encyclopedia
PJM Interconnection LLC is a Regional Transmission Organization
(RTO) which is part of the Eastern Interconnection
grid operating an electric transmission system
serving all or parts of Delaware
, Illinois
, Indiana
, Kentucky
, Maryland
, Michigan
, New Jersey
, North Carolina
, Ohio
, Pennsylvania
, Tennessee
, Virginia
, West Virginia
and the District of Columbia. PJM, headquartered in Valley Forge, Pennsylvania
, is currently the world's largest competitive wholesale electricity market
. More than 650 companies are members of PJM, which serves 51 million customers and has 167 gigawatts of generating capacity. With 1,325 generation sources, 56,000 miles of transmission lines and 6,038 transmission substations, PJM delivered 682 terawatt-hours of electricity in 2009.
, Philadelphia Electric Company
, and Pennsylvania Power & Light Company
formed a power pool called the Pennsylvania-New Jersey Interconnection. The purpose of the power pool was to dispatch electric generating plants on a lowest cost basis, thereby reducing the electric costs for all members of the pool. After Baltimore Gas and Electric Company
and General Public Utilities
joined in 1956, the pool was renamed the Pennsylvania-New Jersey-Maryland Interconnection, or PJM.
(FERC) Order 880 that began the deregulation of the traditional utility companies, FERC began to set up the concepts of an Independent System Operator (ISO) and Regional Transmission Organization
(RTO), which allowed third party entities to manage functions of the electric grid that were traditionally responsibilities of vertically integrated utility companies.
PJM was designated an RTO by the FERC in 2001. FERC regulates PJM and approves its open access transmission tariff
for the wholesale electricity market.
Involvement in the Northeast Blackout of 2003
During the Northeast Blackout of 2003
, the transmission systems within the PJM operations area largely remained operational and were not affected by the power failure.
When the grid separated, a small portion of the Public Service Electric & Gas of New Jersey zone electrically separated from the Eastern Interconnection
due to over-frequency relay operations.
(ComEd) joined PJM as a separate balancing authority operating under the RTO. PJM was able to manage the two territories in a single market by a mechanism known as "the pathway", a set of firm contracts that transferred energy from ComEd through third party control areas to the eastern PJM markets and beyond. In October 2004, American Electric Power
(AEP) and Dayton Power & Light (DPL) joined PJM, which allowed PJM to collapse back into a single control area.
In January 2005, Duquesne Light Co.
(DLCO) joined PJM. In May 2005, Dominion Virginia Power joined PJM, extending the southern border to North Carolina. At this time, PJM now borders 22 balancing authorities representing 11 market interfaces.
for planning transmission system upgrades. Under PJM's Regional Transmission Expansion Planning (RTEP) process, PJM considers forecasts of load growth and additions of demand response
, interconnection requests for new and planned retirements of existing generating plants, and possible solutions to mitigate congestion on the transmission system. If the upgrade involves the construction of a new transmission line, local siting decisions involving the route of the new line are determined by the owner of the line and the state government.
Regional Transmission Organization
A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
(RTO) which is part of the Eastern Interconnection
Eastern Interconnection
The Eastern Interconnection is one of the two major alternating current power grids in North America. The other major interconnection is the Western Interconnection...
grid operating an electric transmission system
Electric power transmission
Electric-power transmission is the bulk transfer of electrical energy, from generating power plants to Electrical substations located near demand centers...
serving all or parts of Delaware
Delaware
Delaware is a U.S. state located on the Atlantic Coast in the Mid-Atlantic region of the United States. It is bordered to the south and west by Maryland, and to the north by Pennsylvania...
, Illinois
Illinois
Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...
, Indiana
Indiana
Indiana is a US state, admitted to the United States as the 19th on December 11, 1816. It is located in the Midwestern United States and Great Lakes Region. With 6,483,802 residents, the state is ranked 15th in population and 16th in population density. Indiana is ranked 38th in land area and is...
, Kentucky
Kentucky
The Commonwealth of Kentucky is a state located in the East Central United States of America. As classified by the United States Census Bureau, Kentucky is a Southern state, more specifically in the East South Central region. Kentucky is one of four U.S. states constituted as a commonwealth...
, Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, Michigan
Michigan
Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....
, New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
, North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
, Ohio
Ohio
Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...
, Pennsylvania
Pennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
, Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...
, Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
, West Virginia
West Virginia
West Virginia is a state in the Appalachian and Southeastern regions of the United States, bordered by Virginia to the southeast, Kentucky to the southwest, Ohio to the northwest, Pennsylvania to the northeast and Maryland to the east...
and the District of Columbia. PJM, headquartered in Valley Forge, Pennsylvania
Valley Forge, Pennsylvania
The Village of Valley Forge is an unincorporated settlement located on the west side of Valley Forge National Historical Park at the confluence of Valley Creek and the Schuylkill River in Pennsylvania, United States. The remaining village is in Schuylkill Township of Chester County, but once...
, is currently the world's largest competitive wholesale electricity market
Electricity market
In economic terms, electricity is a commodity capable of being bought, sold and traded. An electricity market is a system for effecting purchases, through bids to buy; sales, through offers to sell; and short-term trades, generally in the form of financial or obligation swaps. Bids and offers use...
. More than 650 companies are members of PJM, which serves 51 million customers and has 167 gigawatts of generating capacity. With 1,325 generation sources, 56,000 miles of transmission lines and 6,038 transmission substations, PJM delivered 682 terawatt-hours of electricity in 2009.
History
In 1927 the Public Service Electric and Gas CompanyPublic Service Electric and Gas Company
Public Service Enterprise Group , commonly known as PSEG, and originally known as the Public Service Corporation of New Jersey and then as the Public Service Electric and Gas Company, is a regulated, publicly owned gas and electric utility company in the state of New Jersey, United States. It is...
, Philadelphia Electric Company
Exelon
Exelon Corporation is an electricity generating and distributing company headquartered in the Chase Tower in the Chicago Loop area of Chicago. It was created in October, 2000 by the merger of PECO Energy Company and Unicom, of Philadelphia and Chicago respectively. Unicom owned Commonwealth Edison...
, and Pennsylvania Power & Light Company
PPL (utility)
PPL, formerly known as PP&L or Pennsylvania Power and Light, is an energy company headquartered in Allentown, Pennsylvania, USA. It currently controls about 19,000 megawatts of electrical generating capacity in the United States, primarily in Pennsylvania and Montana, and delivers electricity to...
formed a power pool called the Pennsylvania-New Jersey Interconnection. The purpose of the power pool was to dispatch electric generating plants on a lowest cost basis, thereby reducing the electric costs for all members of the pool. After Baltimore Gas and Electric Company
Constellation Energy
Constellation Energy, headquartered in Baltimore, Maryland, is an energy producer, trader, and distributor. The company operates over 35 power plants in 11 states under its operating company Constellation Commodities Group and/or Constellation Generation Group...
and General Public Utilities
FirstEnergy
FirstEnergy Corp. , is a diversified energy company headquartered in Akron, Ohio. Its subsidiaries and affiliates are involved in the generation, transmission, and distribution of electricity, as well as energy management and other energy-related services...
joined in 1956, the pool was renamed the Pennsylvania-New Jersey-Maryland Interconnection, or PJM.
FERC Order 880, 888 and 889
Following the Federal Energy Regulatory CommissionFederal Energy Regulatory Commission
The Federal Energy Regulatory Commission is the United States federal agency with jurisdiction over interstate electricity sales, wholesale electric rates, hydroelectric licensing, natural gas pricing, and oil pipeline rates...
(FERC) Order 880 that began the deregulation of the traditional utility companies, FERC began to set up the concepts of an Independent System Operator (ISO) and Regional Transmission Organization
Regional Transmission Organization
A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
(RTO), which allowed third party entities to manage functions of the electric grid that were traditionally responsibilities of vertically integrated utility companies.
PJM was designated an RTO by the FERC in 2001. FERC regulates PJM and approves its open access transmission tariff
Tariff (disambiguation)
A tariff is a tax on imported or exported goods.A tariff may also refer to:* Tariff, a schedule of prices for the sale or rental of a product or service* Tariff , in British criminal law, a minimum prison sentence...
for the wholesale electricity market.
Deregulation and Expansion, 2002
In April 2002, Allegheny Power (AP) was the first external control area to join the PJM RTO as a market participant; "PJM Classic" and AP operated as a single control area, filling the roles of balancing authority, interchange authority, market operator and transmission operator.Involvement in the Northeast Blackout of 2003Northeast Blackout of 2003The Northeast blackout of 2003 was a widespread power outage that occurred throughout parts of the Northeastern and Midwestern United States and Ontario, Canada on Thursday, August 14, 2003, just before 4:10 p.m....
During the Northeast Blackout of 2003Northeast Blackout of 2003
The Northeast blackout of 2003 was a widespread power outage that occurred throughout parts of the Northeastern and Midwestern United States and Ontario, Canada on Thursday, August 14, 2003, just before 4:10 p.m....
, the transmission systems within the PJM operations area largely remained operational and were not affected by the power failure.
When the grid separated, a small portion of the Public Service Electric & Gas of New Jersey zone electrically separated from the Eastern Interconnection
Eastern Interconnection
The Eastern Interconnection is one of the two major alternating current power grids in North America. The other major interconnection is the Western Interconnection...
due to over-frequency relay operations.
Deregulation and Expansion, 2004-Present
In May 2004, Commonwealth EdisonCommonwealth Edison
Commonwealth Edison is the largest electric utility in Illinois, serving the Chicago and Northern Illinois area...
(ComEd) joined PJM as a separate balancing authority operating under the RTO. PJM was able to manage the two territories in a single market by a mechanism known as "the pathway", a set of firm contracts that transferred energy from ComEd through third party control areas to the eastern PJM markets and beyond. In October 2004, American Electric Power
American Electric Power
American Electric Power is a major investor-owner electric utility in various parts of the United States. AEP ranks among the nation's largest generators of electricity, owning nearly 38,000 megawatts of generating capacity in the U.S...
(AEP) and Dayton Power & Light (DPL) joined PJM, which allowed PJM to collapse back into a single control area.
In January 2005, Duquesne Light Co.
DQE
DQE Holdings is a traditional utility company based in downtown Pittsburgh, Pennsylvania. The company provides electric power to much of metro Pittsburgh, competing with longtime rival Allegheny Power and has extended its services into northern West Virginia and eastern Ohio...
(DLCO) joined PJM. In May 2005, Dominion Virginia Power joined PJM, extending the southern border to North Carolina. At this time, PJM now borders 22 balancing authorities representing 11 market interfaces.
Transmission system planning and upgrades
PJM uses a fifteen year planning horizonPlanning horizon
The planning horizon is the amount of time an organization will look into the future when preparing a strategic plan. Many commercial companies use a five-year planning horizon, but other organizations such as the Forestry Commission in the UK have to use a much longer planning horizon to form...
for planning transmission system upgrades. Under PJM's Regional Transmission Expansion Planning (RTEP) process, PJM considers forecasts of load growth and additions of demand response
Demand response
In electricity grids, demand response is similar to dynamic demand mechanisms to manage customer consumption of electricity in response to supply conditions, for example, having electricity customers reduce their consumption at critical times or in response to market prices...
, interconnection requests for new and planned retirements of existing generating plants, and possible solutions to mitigate congestion on the transmission system. If the upgrade involves the construction of a new transmission line, local siting decisions involving the route of the new line are determined by the owner of the line and the state government.