Ohaaki Power Station
Encyclopedia
The Ohaaki Power Station is a geothermal
power station owned and operated by Contact Energy
. A distinctive feature of this power station is the 105 m high natural draft cooling tower
, the only one of its kind in New Zealand.
Although initially constructed to generate 104 MW, decline in the steamfield has meant maximum net capacity is about 65 MW with an annual output of around 400 GWh pa.
There are currently three turbines in operation. One smaller turbine runs off high pressure steam which then backfeeds into the main intermediate pressure system that feeds the two main units. Condensers on the back end of the main turbines are fed cooled water from the cooling tower to condense the steam back into water. Additional condensate gained in this process is reinjected back into the ground.
in New Zealand
. Gradual sinking of the marae has been attributed to draw-off of geothermal fluids by the power station. The area of the marae is sinking approximately 170mm a year. In the 1960s, the marae was moved to its present location because the previous site was flooded when the dam for the Ohakuri Power Station was filled.
Geothermal
Geothermal is related to energy and may refer to:* The geothermal gradient and associated heat flows from within the Earth- Renewable technology :...
power station owned and operated by Contact Energy
Contact Energy
Contact Energy Limited is a New Zealand electricity generator, natural gas wholesaler and electricity, natural gas, and LPG retailer.The company is the second-largest electricity generator in New Zealand , generating 24 percent of New Zealand's electricity in the year ending 31 December 2009, and...
. A distinctive feature of this power station is the 105 m high natural draft cooling tower
Cooling tower
Cooling towers are heat removal devices used to transfer process waste heat to the atmosphere. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid to near the wet-bulb air temperature or in the case of closed circuit dry cooling towers rely...
, the only one of its kind in New Zealand.
Although initially constructed to generate 104 MW, decline in the steamfield has meant maximum net capacity is about 65 MW with an annual output of around 400 GWh pa.
There are currently three turbines in operation. One smaller turbine runs off high pressure steam which then backfeeds into the main intermediate pressure system that feeds the two main units. Condensers on the back end of the main turbines are fed cooled water from the cooling tower to condense the steam back into water. Additional condensate gained in this process is reinjected back into the ground.
Ohaaki Marae
The plant is located adjacent to the Ohaaki Marae (Ngāti Tahu) on the banks of the Waikato RiverWaikato River
The Waikato River is the longest river in New Zealand. In the North Island, it runs for 425 kilometres from the eastern slopes of Mount Ruapehu, joining the Tongariro River system and emptying into Lake Taupo, New Zealand's largest lake. It drains Taupo at the lake's northeastern edge, creates the...
in New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
. Gradual sinking of the marae has been attributed to draw-off of geothermal fluids by the power station. The area of the marae is sinking approximately 170mm a year. In the 1960s, the marae was moved to its present location because the previous site was flooded when the dam for the Ohakuri Power Station was filled.