A price surge has shocked some Grey Power Electricity customers who believed they had signed on for a capped price.
But a Dunedin customer says despite the rise he would still recommend making the switch.
Grey Power Federation national energy advisory group chairman Allen Davies, of Waiheke Island, said some Grey Power Electricity customers raised concerns when their electricity prices rose.
The rise varied across New Zealand but he had heard customers in Kapiti were disappointed with an 8.2% rise.
A potential price rise was clearly explained in its marketing material, sign-up process and terms and conditions, he said.
''People didn't read what they were sent.''
The terms and conditions detailed a ''price protection rate'' - a level the price could reach, but not exceed, until March 2019.
The prices were raised to the highest possible rate across New Zealand on April 1.
Grey Power Electricity - a partnership between Pulse Energy and Grey Power - had no control of the wholesale price of electricity, he said.
The wholesale price could vary, but he could not foresee a drop, he said.
Pulse Energy buys power from the wholesale market.
Despite the rise, Grey Power Electricity was still competitive in the market and in the past three months its customer base had grown 10%, he said.
Grey Power Electricity customer John Edington, of Dunedin, said he switched from Mercury Energy to Grey Power Electricity after the latest rise.
''It was cheaper with them than what I was paying before.''
He would recommend Grey Power Electricity because customers had the option to terminate the contract at no charge.
In the past, with a bigger power company, he had to sign a three-year contract, he said.
Age Concern Otago chief executive Susan Davidson said it was a constant struggle for many elderly Otago residents to pay power bills.
''Sometimes, it means forgoing buying some food to get the bill paid ... there seems no end to these power price increases.''
A Pulse Energy spokeswoman was unable to provide the April 1 price increase in Otago and Southland last night.
