KEY POINTS:
New Zealand wholesale spot power prices fell for a second week as some winter rains started to fill depleted hydro lakes and a power saving campaign got underway.
Prices at the North Island reference point of Haywards fell 27.4 per cent to an average $254 per megawatt hour (MWh), while at the South Island reference point of Benmore prices were 21.5 per cent lower at an average NZ$303.15 per MWh.
Heavy rains in the catchment areas of the main hydro lakes in the South Island, which have been at their lowest levels since 1992, were the main reason for the fall in prices.
"That's really been it, along with demand levelling off as industrial users have decreased their load and domestic consumers have also responded," an analyst said.
Wholesale market operator M-Co said New Zealand's stored energy over the past seven days increased 10 percentage points to 56 per cent of average.
Hydro lakes are in the so-called "minzone", a technical level of water storage below which authorities look at conservation measures or the greater use of standby thermal plants.
A campaign has started to encourage consumers to conserve energy to preserve hydro lakes levels.
Some industrial users, including the aluminium smelter at Bluff, which is New Zealand's single biggest power consumer, have reduced production to conserve power.
Total demand fell 3.5 per cent to 106,645 MWh.
National inflows were 83 per cent of average over the week to Tuesday, compared with 51 per cent in the previous week.
In the South Island, where virtually all power is produced by hydro power stations, inflows were 86 per cent of average compared with 45 per cent the previous week, while North Island inflows were fractionally higher at 69 per cent of average.
"The inflows have tapered off now, so we're probably going to return to that trend of declining storage levels for a while, but the savings have bought us another week if not more," the analyst said.
Expensive gas and coal fired power stations in the North Island have been operating at full capacity and sending power south through the inter-island high voltage cable to preserve hydro resources.
Yesterday the government said it would ban energy-wasting incandescent light bulbs from late next year to cut lighting energy consumption by 20 per cent by 2015.
- NZPA
