Supriya Ghosh (Editor)

New Plymouth Power Station

Updated on
Edit
Like
Comment
Share on FacebookTweet on TwitterShare on LinkedInShare on Reddit
Country
  
Primary fuel
  
Cogeneration?
  
No

Decommission date
  
2008

Status
  
Decommissioned

Secondary fuel
  
Fuel oil

Owner
  
Units operational
  
5

New Plymouth Power Station IPENZ Engineering Heritage

Location
  
Similar
  
Paritutu Rock, Sugar Loaf Islands, Puke Ariki, Mount Taranaki

Construction of the new plymouth power station


The New Plymouth Power Station (NPPS) was a 600 MW thermal power station at New Plymouth. Located at Port Taranaki, it was dual fuelled on natural gas 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.

Contents

New Plymouth Power Station IPENZ Engineering Heritage

The plant has been owned and operated (in turn) by NZED, NZE, ECNZ and Contact Energy. In 2013, the site was sold to Port Taranaki and Methanex.

New Plymouth Power Station IPENZ Engineering Heritage

What if new plymouth power station chimney future scenarios


History

New Plymouth Power Station httpsstatic2stuffconz13546452175868037586jpg

The power station project commenced in the 1960s, to meet rising electricity demand in New Zealand. 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. During early stages of the project, the Maui gas field was discovered off Taranaki. The plant design was changed to be dual fuel on either natural gas or heavy fuel oil.

New Plymouth Power Station Port to see how station deal stacks up Stuffconz

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 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 and 2003), 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 Contact Energy to close the power station.

In May 2008, one 100 MW unit (unit 3) was temporarily recommissioned. 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.

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 are balanced draught with tilting burners mounted in the corners of the furnace. Each boiler produces 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. 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.

References

New Plymouth Power Station Wikipedia