The National Energy System Operator (NESO) has released the results of its T-4 Capacity Market (CM) auction, with battery storage gaining 3% of liabilities and gas and interconnectors gaining the largest share.
The T-4 auction for delivery in 2029/30 concluded last week (March 10) with 40,108,608 MW of commitments, above the target of 39,400 MW.
The clearing price was £27.10/q/yr, down more than 50% from last year’s £60/q/yr.
Gas projects won 58.5% of the allocated capacity and interconnectors won 19.5%.
Battery energy storage system (BESS) projects gained 1,224 MW of commitments, 3.05% of total capacity, while pumped hydro storage gained 1,352 MW, 3.337% of the total (the two combined total about 6.4%).
Other notable winning technologies were run-of-river hydropower at 3.06%, demand response (DSR) at 6.4% and nuclear power at 2.3%.
Solar energy gained 13 MW, 0.03% of the total. As a non-dispatchable technology, it is not well suited to the CM, which pays assets for being available at specific times in the future when NESO predicts a risk that there is not enough supply to meet demand.
It follows the T-1 CM results, which were released a few days earlierthat only purchases one year in advance and is smaller in size.
Notable owner-operators who won contracts for their battery storage projects included Grenergy, Gresham House, Amp Clean Energy, Eku Energy, European Energy, Harmony Energy and many more. The CM is generally used to cover a small portion of a battery project’s revenue.
Technologies also have different derating factors, a percentage that limits how much of your rated megawatt (MW) capacity you can provide. This is generally highest for gas and nuclear energy, lower for storage and very low for solar energy.
View NESO’s full T-4 preliminary results report herewith a complete list of winning projects by technology type and ownership.
