Auckland comes off relatively lightly in Powershop analysis compared to stiff regional hikes as high as $133.

Home electricity bills rose by $63 on average in the 12 months to February, with the biggest increases generally occurring in some smaller cities and their large rural hinterlands.

Dunedin got off lightest, with an increase of $9, and Auckland came second at $13, a rise of just 0.6 per cent in the retail price, weighted by retailers' market shares.

At the top end of the scale, families and other domestic power users in Nelson/Marlborough suffered the biggest increases, of $133 (6.2 per cent), followed by the East Coast on $128. The figures come from an analysis - done by small retailer Powershop - of survey data published by the Ministry of Business, Innovation and Employment.

Powershop shows up in the ministry data as having imposed increases towards the upper end in some of the areas where it operates. In the Auckland area fed by the Vector lines network, for instance, Powershop's retail price rose by 4.1 per cent in the 12 months, approaching double the 2.3 per cent increase of the area's biggest retailer, Mercury Energy.


Powershop's price per unit of electricity was, however, still lower than Mercury's at the end of the survey period. "We had a [price] catch-up last April," said Powershop's chief executive, Ari Sargent.

"We were lagging behind on previous years on recovery of line costs and metering costs."

He said there had been a lot of "finger-pointing" in the industry over price rises, "with retailers blaming lines companies and Transpower and them fighting back. Retailers should take responsibility for their own prices, cut costs where they can and help customers to save power."

Mr Sargent said the national 2.9 per cent increase found by the survey was lower than the rises in the preceding two years, because of the declining contribution of big increases in electricity transmission prices.

"We expect price increases from now on to be much closer to inflation," he said.

His company's analysis also calculated how much money an average consumer could save in each region if they switched from the dearest to the cheapest retailer - more than $100 a year everywhere except Southland.

The East Coast's Wairoa area topped the list with potential savings of $656 a year; Tauranga came ninth on $538; and Aucklanders on the Vector network 24th on $363.

Mr Sargent urged people to shop around for the best deal, but also noted many were locked into fixed-price contracts carrying stiff break fees if they tried to switch retailer.


Domestic Energy Users' Network convener Molly Melhuish said: "Prices have always been higher in the regions. Competition has brought prices down significantly in the regions, but they are still higher than where competition is strong."