The Department for Energy and Climate Change says it has "needed to drive through reforms to secure investment in new generation to keep the lights on in the years and decades ahead" after suggestions it may have cost consumers by awarding eight renewables contracts too early.
A spokesperson said the National Audit Office's report recognises that the early deals were "designed to offer better value to bill-payers" by reassuring investors.
"Without that investment, projects would have been unable to go ahead or been significantly delayed - putting our future energy security at risk."
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A year ago the International Court of Justice ruled that Japan's decades-old whale hunt in the Antarctic should stop.
Shadow chancellor John McDonnell has backed a free vote for MPs on the issue.
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