Most regions from South Canterbury to Invercargill seem likely to benefit from proposed changes to New Zealand's electricity pricing, although there is still a long way to go before any changes are finalised.
Waitaki appears to be a loser in the proposed pricing changes and Otago is seen as neutral.
After a much-anticipated wait, the Electricity Authority released its consultation paper outlining the proposed changes to setting the transmission pricing methodology (TPM).
Electricity Authority chief executive Carl Hansen said the current TPM was complex and sent the wrong price signals to transmission users, resulting in wasteful investment.
The economic cost to New Zealand exceeded $200 million.
"If no change is made, in the future comsumers could pay hundreds of millions of dollars more for electricity than necessary.''
The authority estimated consumers were paying distributed generators $25million to $35million each year for which they were not receiving any benefit in terms of reduced transmission costs, he said.
That meant consumers were paying higher electricity prices than would otherwise occur.
The proposed changes would mean over the next 15 years, consumers would pay up to $325million less in electricity charges, Mr Hansen said.
"Our statutory objective is to promote an electricity market that creates long-term benefit for consumers. We do not believe the current pricing rules for distributed generation do that.''
While distributed generators could provide valuable support services, they needed to pay an efficient share of network costs. The proposal would make the market more level for all generators and ultimately encourage more efficient investment decisions, he said.
The immediate overall impact of the proposal on the average residential electricity bill was fairly modest. In 15 regions, electricity consumers' bills would fall. In the remaining 14 regions, the average bill increase was less than $50 a year.
Mr Hansen said the regions where consumers would have an increase in their bills were those that had benefited from substantial recent grid upgrades to improve service levels, or where transmission prices had been lower than average.
In every region, the benefit from those recent investments greatly exceeded the area-of-benefit charges proposed to pay them.
Green Party energy spokesman Gareth Hughes claimed the authority could force some households to pay hundreds of dollars a year for more power to subsidise big business users, making it even harder for families to warm their homes.
A table in the authority's issues paper showed Electricity Ashburton bills would increase by between $102 and $117 a year, Top Energy bills would increase by $21.87 and Northpower bills would increase by more than $36.
In contrast, Aurora Energy bills could fall by up to $57 a year, Electricity Invercargill bills would fall by $64 and Network Waitaki bills would increase by $21 a year.
Mr Hughes said major industrial users would have more scope to apply for special discounts.
"The fact is, higher power prices make for colder families and sicker children in winter. The Electricity Authority should be treating the electricity network as a national asset for the benefit of all New Zealanders, not playing people who live in different regions off against each other while cutting the Tiwai Point aluminium smelter's power bill by $20 million.''
Parts of the authority's document read as if people would get up and move their lives around the country to maximise economic efficiency in the power grid, which was ridiculous, he said.
It was also concerning Kiwirail's annual power transmission bill could jump from $500,000 to $2.3 million at a time when Kiwirail should be helped to move more freight off the roads and on to rail.
The authority table showed Carter Holt Harvey would face electricity bills $2 million a year higher, New Zealand Steel's bill would rise from $4.6 million to $16.7 million, Rayonier's bill would fall to $600,000 and the New Zealand Aluminium Smelters operation at Tiwai Point would benefit by more than $20million.
At a glance
Winners: Invercargill, South Canterbury, Central Otago and Dunedin, Queenstown, Hawke's Bay, East Coast, North Canterbury, Marlborough, Tasman, Christchurch, Western Bay of Plenty/Taranaki, Tararua, Southland, Rotorua, Waikato North, Wellington.
Losers: Ashburton, Westport, South Auckland, Eastern Bay of Plenty, Waitaki, Whangarei, Waikato, Northland, Auckland, Hokitika.
Neutral: Horowhenua, Otago, Hamilton.
