Speaking at the International Small Wind Conference in Watford, hosted by the British Wind Energy Association, he said: "Without being defeatist, there will inevitably be problems within the feed-in tariff in the UK."
"We'll need to review it and we'll need to make changes on an ongoing basis. Please don't expect our feed-in tariffs to be perfect from the start," he added.
The proposed feed-in tariff was announced during chancellor Alistair Darling's Budget speech, as part of a package of new renewable energy considerations, in the House of Commons on Wednesday.
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