This is the third in a series of posts that look at UK Wind Power, in particular at its ability to contribute to peak demand, which occurs in the early evening, reaching its highest values during winter cold spells. Of particular interest is the wind power produced on the coldest evenings.
Data at 5-minute intervals for demand and metered wind power were downloaded from the gridwatch website ( http://www.gridwatch.templar.co.uk/download.php ) and plotted so as to reveal its essential characteristics.
The figure below shows the daily peak demand (in red) and metered wind power (in blue) at the times of the daily peak demand, for 2013/14:
The winter of 2013/14 was exceptionally mild, as can be seen from the fact that demand for December to February barely rose above that for November and March, and peak demand never rose above 54 GW.
Wind power was intermittent, with several days of very low output at the times of peak demand, but there were periods of sustained storminess during which the wind never stopped blowing.
The UK Met Office provides the following summary of winter 2013/14:
“Winter 2014 was an exceptionally stormy season, with at least 12 major winter storms affecting the UK in two spells from mid-December to early January, and again from late January to mid-February. When considered overall, this was the stormiest period of weather experienced by the UK for at least 20 years. An analysis of pressure fields by the University of East Anglia suggests this winter has had more very severe gale days than any other winter season in a series from 1871.”
In the winter of 2013/14 there were no combinations of high demand at the same time as low wind power. Wind power achieved relatively high average capacity factors, but there were several days of very low wind power at the times of peak demand.