GE, the US-based equipment supplier, had completed the initial internal inspection of the gas turbine and confirmed that it had suffered significant internal damage.
The peakers play an important role, not just in Contact’s portfolio, but also for the wider electricity market in terms of energy security.
“At this stage, we could be looking at February/March 2025 before the GT22 is returned to service, resulting in a prolonged outage,” the company said.
“We are working with our original equipment manufacturer to determine if there are other options to reduce the outage time. However, at this stage, we believe this likelihood is slim.”
Contact expects to have TCC, the other peaker unit, and the Whirinaki units available throughout 2024.
Energy Link managing director Greg Sise said the outage could have far-reaching implications for the market.
“We have been running our latest forecasts and yes, it does have an impact,” he told the Herald.
TCC, commissioned in 1996, can generate 360 megawatts of electricity.
In 2011, Contact commissioned the Stratford Peakers next to TCC.
The two fast-start gas turbine peaking units can go from a cold start to full load in just 10 minutes and generate up to 200 MW.
Sise said Contact could keep TCC - which it wants to retire next year - running for longer.
Contact and Genesis Energy’s thermal assets kick in when the hydro lakes are low or in times of abnormally high demand, such as a cold snap.
He said it was possible that Genesis could end up running its Huntly coal and gas-fired Rankines - Units 1, 2 and 4 - more than the company had expected as a result of the outage.
The Stratford peaker’s outage would mean the loss of “significant” peaking capacity.
“Huntly is a bit more flexible in terms of what it can do when it is running - it can do quite a bit of peaking in its own right - but the units are very slow to start up.”
However, Sise said there was a lot of power-generating capacity to come on-stream this year and next, which would alleviate the supply situation.
Stage one of Mercury’s Kaiwera Downs wind farm, near Gore, is expected to be operational by the end of this year.
Contact’s Tauhara geothermal power station, near Taupō, is expected to be complete and operational late this year, while its Te Huka Unit 3 is due for completion late next year.
Meridian’s Harapaki wind farm, currently being built in Hawke’s Bay, is expected to start generating power next month.
Sise noted the growing uptake of electric vehicles would increase demand for electricity.
“That will only take off relatively slowly, for a start,” he said.
“So we are getting all this generation coming in, with relatively low demand growth - if any - over the next year, so here is a real benefit of having all that new plant,” he said.
Last month, Genesis Energy said an outage at its Unit 5 combined cycle gas plant at Huntly would cost $20-$30 million.
Unit 5, which usually delivers continuous or baseload power to the electricity grid, has been out of action since June 30.
Genesis had earlier advised that it expected Unit 5 to return to service by August 31, but it has now pushed that date out to May next year.
High hydro storage, alternative plant availability and wholesale electricity market conditions have combined to mitigate the financial impact of the outage to date, Genesis said.
Jamie Gray is an Auckland-based journalist, covering the financial markets and the primary sector. He joined the Herald in 2011.
