During the first cold snap of the winter, prices in the UK power pool rose to record high levels, exceeding $1.60/kWh on at least two occasions. The reason -- unexpected outages of nuclear, coal and gas plant. For the third successive year, however, wind was available to the system at the peak periods, confounding its critics and confirming numerous studies. On the first day of record pool prices, for example, winds were fairly light in the southwest of the country, but the wind farms still generated. Winds were stronger in the north of England and during the peak demand period a wind farm at Coal Clough, operated by Renewable Energy Systems, recorded a capacity factor of 0.3. "This reinforces the point that wind, contrary to popular opinion, is not fundamentally different from thermal plant, and it does have a capacity value," says wind consultant David Milborrow. "The claim -- often made -- that thermal plant can be trusted to generate for 365 days every year is looking rather shaky."