New trading arrangements were introduced in March and have cut wholesale prices but critics say they penalise small generators, such as wind farms and combined heat and power plants, which have unpredictable output.

Wilson said he would soon publish proposals aimed at addressing the concerns of smaller generators. They would be put out for consultation, he said.

Britain has set itself a target that 10 percent of the country's electricity will come from renewable sources by 2010. Wilson said it was his job to deliver on that target but industry experts said the current regime made the goal harder not easier to reach.

David Green, from the Combined Heat and Power Association, said several energy schemes were being shelved and others cut back, meaning carbon dioxide emissions would rise.

"It's getting to a real state of crisis," he told BBC radio. "There is a significant meltdown taking place now."

But Wilson said in many respects, NETA had delivered "spectacular results".