Former Energy Minister Max Bradford is defending his energy reforms against criticism from Opposition parties.
The former National minister deregulated the power market in 1997 in a move Labour and the Greens say has led to higher electricity prices.
Speaking to TV3's The Nation programme on Sunday, Mr Bradford said prices had fallen until Labour went into Government and started fiddling with the market.
He says a competitive market will lead to falling prices or prices that rise more slowly.
Mr Bradford says the Labour-Greens policy of a single purchaser of electricity will increase the costs of the industry quite substantially.
Meanwhile, New Zealand First leader Winston Peters says he believes Labour and Green supporters are likely to support his plan to buy back partially-sold power companies.
New Zealand First wants to create a national power generator by combining Mighty River Power, Genesis and Meridian, and cap power price increases to the official inflation rate.
The party is not supporting the Labour and Green policy to create a single purchaser of electricity.
Mr Peters told The Nation his policy of creating a national generator was a better solution and there would be 80% support for the country's power generation assets being owned by the Government.
He said his power policy will be one of those to be discussed during any negotiations to form a government after the next election.