The New Plymouth Power Station (NPPS) was a 600 MW

thermal power station A thermal power station is a type of power station in which heat energy is converted to electrical energy. In a steam-generating cycle heat is used to boil water in a large pressure vessel to produce high-pressure steam, which drives a stea ...

at New Plymouth, New Zealand. Located at Port Taranaki, it was dual fuelled on

natural gas Natural gas (also called fossil gas or simply gas) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane in addition to various smaller amounts of other higher alkanes. Low levels of trace gases like carbo ...

and fuel oil. Constructed at a time of major hydro and HV transmission developments, it was New Zealand's first big thermal power station planned for continuous base load operation. The plant has been owned and operated (in turn) by NZED, NZE, ECNZ and

Contact Energy Contact Energy Limited is a New Zealand electricity generator, a wholesaler of natural gas, and a retailer of electricity, natural gas, broadband and LPG. It is the second-largest electricity generator in New Zealand (after Meridian Energy), g ...

. In 2013, the site was sold to Port Taranaki and

Methanex Methanex Corporation is a Canadian company that supplies, distributes and markets methanol worldwide. Methanex is the world’s largest producer and supplier of methanol to major international markets in North and South America, Europe, and Asia ...

History

The power station project commenced in the 1960s, to meet rising electricity demand in

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. Initially, fuel for this power station was to be coal, barged up from the West Coast, and the Port Taranaki site was chosen ahead of one at

Wanganui Whanganui (; ), also spelled Wanganui, is a city in the Manawatū-Whanganui region of New Zealand. The city is located on the west coast of the North Island at the mouth of the Whanganui River, New Zealand's longest navigable waterway. Whang ...

. During early stages of the project, the Maui gas field was discovered off

Taranaki Taranaki is a region in the west of New Zealand's North Island. It is named after its main geographical feature, the stratovolcano of Mount Taranaki, also known as Mount Egmont. The main centre is the city of New Plymouth. The New Plymouth D ...

. The plant design was changed to be dual fuel on either natural gas or heavy fuel oil. The first unit was commissioned in February 1974, with the fifth unit coming on line in 1976. For the first few years, the plant ran on raw

Kapuni Kapuni is an onshore natural gas-condensate field located in the Taranaki Basin, a ~100,000 km2 partially-inverted rift basin on the Taranaki Peninsula in the North Island, New Zealand. Discovered in 1959 and brought into production in 1970 ...

gas. In 1979, the plant converted to Maui gas following the completion of the pipeline from Oaonui production station. The pipeline from Kapuni was re-purposed to supply Maui gas to Kapuni and onwards to the lower North Island. The fuel oil capability was decommissioned in 1991, and reinstated in 2003. Plant operation generally decreased from 1999, after the more efficient Otahuhu combined cycle power station was commissioned. However, the New Zealand power system derives over 60% of its electricity supply from hydro power stations and depends heavily on rainfall. NPPS has often played a vital role in dry years (such as 2001, 2003 and 2008), when hydro lake inflows were insufficient to meet demand. Discovery of asbestos, not in an asbestos register, in thermal insulation during 2007 led to the decision by

to close the power station. In May 2008, one generating unit (unit 3) was temporarily recommissioned, with a capacity of 100MW. This was in response to a nationwide electricity generation shortfall resulting from low hydro lake levels. This unit was shut down for decommissioning in December 2008. In 2013, most of the site was sold to Port Taranaki, with Methanex purchasing a part of the site that held methanol tanks. In 2014 and 2015, the power station equipment was removed and the boiler house demolished, with all the plant, piping and structure being sold as scrap metal.

Plant

The power station comprised five identical units, each rated at 120 MW. The boilers were provided by ICL of Derby UK, and the steam turbines were by C A Parsons of Newcastle, UK. The boilers were balanced draught with tilting burners mounted in the corners of the furnace. Each boiler produced 376 tonnes/hour of steam at 120 bar and 538 °C, with one stage of reheat to 538 °C. The steam turbines are 3000 rpm single-shaft, three-cylinder (HP, IP and LP) design, with six stages of feed heating. The condenser is a two-pass tubed design, using seawater as the coolant. The generators are two-poled, hydrogen cooled. Condenser cooling is seawater, with a flow of 12,000 tonnes/hour for each unit. The chimney is 198 m high, and contains five flues. It is the second tallest structure in New Zealand.

References

External links

Port Taranaki
{{New Plymouth District Natural gas-fired power stations in New Zealand Buildings and structures in New Plymouth Oil-fired power stations in New Zealand 1974 establishments in New Zealand 2008 disestablishments in New Zealand

History

Plant

See also

References

Further reading

External links