Britain is walking a tightrope with electricity supply as this incident shows. We’re in a minor heatwave at present and daylight hours are long.
H/T Daily Telegraph
A series of power plant breakdowns and the partial failure of a key electricity import cable forced National Grid to issue an urgent call for more power to keep the lights on on Monday night.
One power plant was paid more than 30 times the usual price of power after the Grid issued the “Notification of Inadequate System Margin” (Nism) requesting more electricity be generated. A Nism alert has not been issued in summer months since 2008 as the warm weather means power demand is normally lower.
But the combination of a large number of power plants being shut down for maintenance, the series of unplanned shutdowns and wind power being lower than expected together forced Grid to take the unusual step.
Experts said the multiple breakdowns – believed to be primarily old coal and gas plants – showed the urgent need for more investment in reliable new power plants. National Grid said about 1,700 megawatts of capacity was unexpectedly taken off the system yesterday.
In addition, a problem forced the part closure of a National Grid-owned interconnector cable importing power from France, with the loss of another 500 megawatts.
At the same time, Britain’s wind farms generated about 500 megawatts less power than expected. National Grid issued an alert at 7pm calling for 1,500 megawatts of power plant capacity to start generating between 7pm and 9.30pm.
National Grid said the highest price it paid to a plant to help it through the crunch was £1,250 per megawatt-hour of power. It is understood this was to E.On’s Connah’s Quay power plant.
Nism alerts used to be relatively common but had barely been used in the last few years due to a healthy surplus of power plants on the electricity grid. However, that surplus is being eroded as old coal plants are mothballed and shut.