Power station repairs strain NI supplies

By Mark Reynolds

A breakdown at a new gas-fired electricity plant at Stratford is continuing to put a strain on electricity supplies to the upper North Island.

The Taranaki Combined Cycle plant was shut down on May 7 for what was to have been a month of repairs. But the facility is still out of commission and is now unlikely to be fixed until the end of this month.

It is capable of producing 350 megawatts of power, or around 4.5 per cent of the nation's total power production capacity. But while the plant is relatively insignificant in terms of national production, it has a key role in ensuring a ready supply of power for Auckland.

That is especially the case now because of an outage at one of the Huntly power plant's four 250 megawatt generators and continued delays in getting Contact Energy's new 390 megawatt Otahuhu B plant up and running. The situation is also complicated by some transmission constraints in parts of the North Island that make it difficult at times to move north power from hydro-powered facilities in the south.

Electricity market traders said the continued Stratford outage was pushing up wholesale power prices and the situation could be exacerbated if cold winter conditions take hold over the next week or two.

A TransAlta spokesman said the plant "was scheduled for return next week, but will be pushed back for at least one more week."

The Stratford plant is owned by TransAlta. Construction of the plant was completed only last year.

Contact's new Otahuhu B facility is now expected to be completed by September while plans to repair the fourth Huntly unit, damaged by fire earlier this year, are still being drawn up.