Wellington, April 1 NZPA - With winter on its way, Genesis Energy is increasing power prices for more than 75,000 residential electricity customers from May 17.

About 17,000 Auckland customers in Vector lines area will pay an extra 2.8 percent. This includes increases in Vector's fixed charges.

About 58,000 northern Waikato consumers face a 3.8 percent increase, including lines company price increases, The New Zealand Herald reported.

Prices will also rise for some lower South Island customers, although some will also have price reductions.

Genesis general manager retail Dean Carroll said the increases were driven by rising energy and network costs. In Waikato the most recent previous increase by the company was a year ago, while in Auckland it was last June.

"We have held increases back as long as possible recognising that households are under increasing cost pressures," he said.

"We recognise that we need to act responsibly when it comes to price changes and have factored that into the level of the increases."

The company was also carrying out a comprehensive review of spending across the business to ensure customer confidence could be maintained. Contact Energy's 70,000 gas customers throughout the country also face increases from next month.

Charges will go up by a flat rate of 13.5c a day from May 1.

The company said the price it paid for wholesale gas had increased by 25 percent.

It has taken the sting out of the rise by increasing its discount for customers who have Contact electricity and gas from 10c a day to 40c a day.

Meridian Energy said last month it would increase power bills for 180,000 customers by an average of 6.5 percent, on top of a 6 percent increase last September.

It said it had already absorbed a lot of cost increases and had no choice but to pass on the cost of boosting its generating capacity.

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