KEY POINTS:
A report on eletricity use released today confirms that we should be able to get through the winter unscathed, provided the lakes get a reasonable amount of rainfall during the autumn months.
There were concerns hydro lake storage were dipping to levels seen before the 1992 power crisis.
The National Winter Group (NWG), a collection of industry representataives, today released their updated report on the ability of the power system to meet peak winter demand.
Details of measures to cope with any electricity shortages are available here.
The NWG outlined more about how big users can help in saving power in the event of shortages and progress on the restoration of part of the interisland high voltage link.
Importing generators has also been considered as a backup option although Energy Minister David Parker has said they would be run for hours rather than days as a secondary line of defence.
Most of New Zealand's power comes from hydro storage lakes which were yesterday at 73 per cent of average levels for this time of the year, and down 4 per cent on a week earlier, according to the market operator M-Co.
While steady, heavy rain can fill South Island lakes in less than 10 days, the late summer and autumn Niwa outlook is for a 50 per cent chance of a continuing dry spell in the catchment.
In the North Island Mighty River Power's hydro network on the Waikato River is fed from Lake Taupo where inflows during the past six weeks have been at their lowest in 82 years of records.
The state owned enterprise says the level of Lake Taupo is currently around 356.36m above sea allowing 36 per cent of its operating range (of 1.4m) remaining.
There was still room for the lake level to decline further if inflows remained below average.
Mighty River's Southdown gas-fired co-generation station at Penrose is operating at full output to preserve storage.
The 1992 crisis resulted in street lighting being shut off in some areas, hot water heating being cut for most of the day and television stations shutting down early at night. Comalco shut down a potline at the Tiwai Point aluminium smelter and generators from ships were used to supplement power supplies.
Power industry veterans say winter will be tight but manageable and Prime Minister Helen Clark says she does not believe there is a looming "power crisis" and has blamed opposition MPs for sensationalising the issue.
Supply during much of summer has been critical as hydro generators conserve water, Contact Energy's 357MW Stratford plant is out for maintenance, there are constraints on generation from Huntly due to high river temperatures, and calm days are cutting generation from wind turbines.
Major Electricity Users Group executive director Ralph Matthes said the winter group's work should ensure there was contingency cover for mid-winter peak demand.
Bringing back Pole One of the interisland link would give the country some extra breathing space.
Insurers withdrew cover of the ageing equipment last year but Transpower said last week it was growing increasingly confident new insurance could be found.
He said the hydro lake storage levels were a concern but there was "no need to panic".
"It's going to rain between now and winter, the only thing is whether it's going to be enough to give us cover if one of the thermal generators has a major breakdown," Matthes said.
Wholesale spot power prices rose last week underpinned by low hydro lake inflows.
Prices at the North Island reference point of Haywards rose 8.2 per cent to an average $124.89 per megawatt hour (MWh), while at the South Island point of Benmore prices were 7.2 per cent higher at an average $119.44 per MWh.
Matthes said he was more concerned about future years given the proposed Government ban on building new baseload power plants that burn fossil fuels. Also rules had not been established for short term peaking plants, and this meant it was almost too late to build anything.
"Next winter demand will grow but where is the new peaking plant to offset that." He said the strategy was "a complete cock-up and the Government should retract it".
- Additional reporting NZPA, NZHERALD STAFF
