A recent post gave a quantitative estimate, for the GB electricity grid, of the wind power at peak demand time expected in 2016/17 if there is a repeat of the recent coldest winters. This post extends the analysis back to the winter of 1975/76, again with particular interest in the wind power expected on the coldest (highest demand) days.
We saw in the analysis of recent winters that whenever the estimated wind power was low the synoptic chart for the day in question confirmed the estimation from the wide spacing of isobars. In this post the synoptic charts are used directly to provide a qualitative assessment of the amount of wind power expected.
First of all the coldest days were identified for the winters between 1975/76 and 1984/85, via a threshold of zero degrees C applied to the daily maximum of the Central England Temperature (HadCET) series:
The HadCET page of this blog allows the temperatures in this period to be seen in the context of the entire HadCET Tmax record, which extends back to 1878 (this analysis still has a long way to go!). The cold spells are discussed below.
1977 January 12th: The following synoptic chart indicates that this was a calm day, and wind power at 2016/17 levels would contribute little to peak demand:
WINTER 1978/79
December 19th 1978, Light winds:
December 31st 1978, Very Windy:
January 5th 1979, Low wind power:
February 14-17 1979, varied winds, light on 17th:
WINTER 1981/82
December 10-12 1982, Light Winds:
December 16/17 1981, Light Winds:
January 7-14 1982, Variable winds, light on some cold days:
WINTER 1984/85
January 7 1985, Light Winds:
January 13-16 1985, Light to Moderate Winds:
February 9-15 1985, Moderate to Strong Winds:
Conclusions
This period contained some very cold and calm days, and the electricity system of 2016/17 and beyond will have to be able to meet their electricity demand without wind power.