Even on a calm day, turbines can still keep the lights on, says think tank

Published on 31/08/2012 01:58

Wind power in Britain cuts carbon emissions significantly and is predictable enough that the grid can rely on it to help keep the lights on, despite spells of cold, calm weather, the Institute for Public Policy Research (IPPR) said yesterday.

Critics have said wind power cannot be relied upon at times that demand is the greatest, cannot be stored and does not cut enough carbon to make large investments worthwhile.

“The reliability and security of wind power does not depend on the variability of wind but instead on how well changes in wind power output can be predicted and managed,” the IPPR said in its report.

Carbon savings from some 15.5 terrawatt hours of wind energy in Britain in 2011 amounted to at least 5.5 million tonnes, or about 2.5 per cent of the emissions the UK has promised to cut over 2008-2012, the report said.

In July, the UK cut subsidies for onshore wind by 10 per cent from 2013, but some investors expected a reduction of 25 per cent.

Wind-farm output can be forecast 24 hours ahead. Statistical analysis shows the most extreme changes in output amount to about 20 per cent of total wind generation capacity in half an hour, the report said.

In the worst case, wind production could drop as electricity demand is rising.

“However it is important to reiterate that changes in wind production are to a large degree predictable: the operators can see rapid changes coming, or, at the very least, be forewarned of the risk of rapid changes,” the report said.

“On the rare occasions when this could cause difficulty, electricity system operators can instruct the wind generation segment of the system to limit the rate at which its output increases or to reduce its output gradually in advance of a reduction in wind speed.”