by Dr Iain Staffell – Imperial College London
March 1st was the coldest spring day on record, averaging –3.8°C. This pushed electricity demand up 10%, and prices up by 50%.
The six days from February 26th to March 3rd (highlighted in blue) were the coldest Britain has been since Christmas 2010.
This pushed electricity demand up 10%, as people used more electric heating to keep warm. The evening peak demand on March 1st was 53.3 GW: the highest in three years, but not enough to stretch the system to its limits.
Electricity prices reacted sharply though, peaking at £990 per MWh for half an hour, and also falling to –£150 per MWh as the market became volatile. The average power price in March was 50% higher than March 2017 as a result.
Coal generation surged for the weeks surrounding the cold spell. Not because more output from conventional plants was needed: total generation from fossil fuels remained steady, averaging 20–25 GW. Instead, rising gas prices made it temporarily more economical to burn coal.
Wind output was particularly high when it was most needed, ranging from 11.8 to 13.8 GW during March 1st. On the other hand, solar panels averaged just 0.2 GW on that day, as the blanket of snow shielded them from the sun.
Biomass ran solidly throughout the cold spell, while two nuclear reactors were down for routine maintenance, and seaweed forced a third to shut on the coldest day!
Finally, Electric Insights itself was not immune to the cold weather. Traffic to the website surged to 10 times its usual level on March 1st and 2nd.
Authors: Dr Iain Staffell, Professor Richard Green, Dr Rob Gross and Professor Tim Green.