National Grid has fired up a coal-fired power station for the first time in 55 days after Britain’s record-breaking heatwave brought wind turbines to a near-standstill and caused gas-fired power stations to struggle.
The electricity system operator brought Britain’s latest coal-free streak to an end by calling for the Ratcliffe-on-Soar power station in Nottinghamshire to begin generating electricity before a peak in electricity demand.
Electricity supplies have become tighter than expected during the heatwave because gas-fired power stations have struggled to generate electricity at their maximum capacity owing to the unusually high temperatures. At the same time wind turbines have slowed because of low wind speeds.
A string of power stations were unable to produce electricity on Wednesday because of planned maintenance work which often takes place during the summer, but even available gas plants produced less electricity than usual owing to the heat.
Gas plants can struggle to produce electricity at normal levels during high temperatures, according to experts at the energy data company EnAppSys, and it is normal for their power output to fall during heatwaves. They rely on a steady flow of air through its compressor, according to the energy technology firm Wartsila. It takes more energy to compress hot, humid air to the same mass as air which is cooler and drier, so many power plants become less efficient as the outside temperature rises.