On Monday 24 June, the electricity system price in the UK spiked to £375/MWh for three consecutive settlement periods between 11am and 12:30pm, prompted by a run on coal generation units at both Ratcliffe and Burton.
Drax Electric Insights, which monitors UK power generation and the system price, shows the spike occurring, before dropping back down to below £30/MWh.
That 90-minute period sent the average system price for the day up to £75.52/MWh, more than double the average system price for the prior Monday (£33.12/MWh).
The need for coal power to return to help balance the grid was attributable to a range of factors, most notably lower than average renewable generation with cloudy skies and low wind speeds.
Contribution from the UK’s nuclear fleet is currently stymied by planned outages, and it’s a similar story for the country’s interconnector with France, which has seen its capacity limited to 1GW.
System price volatility has been rife in the UK market this summer, with significant renewable output prompting periods of negative pricing and increased calls for more flexibility in the system, particularly as battery storage assets have been able to adjust their charge and discharge patterns to benefit the system and their revenue base.
Speaking to Current±, a spokesman for energy aggregator Limejump said that it used its assets under management to take control of the opportunities on the intraday exchange market, which saw prices rise above those on the Balancing Mechanism during the same period.
“These trading decisions provide customers with more opportunities to access revenue both inside the Balancing Mechanism, and outside in other markets like the intraday market,” the spokesperson said.