Question to the Department for Energy Security & Net Zero:

To ask the Secretary of State for Energy Security and Net Zero, what recent assessment he has made of the viability of expanding the utilisation of compressed air energy storage in the energy grid.

There is already 2.8GW of pumped storage hydropower (PSH) on the GB electricity system, which is a form of Long Duration Electricity Storage (LDES). The government agrees that GB needs more LDES, which is why the Clean Power 2030 Action Plan envisages an expansion of capacity of 1.2 to 3.2 GW by 2030 compared to today’s level and also why the National Electricity System Operator (NESO) has published advice that 2.7 to 7.7 GW more LDES is required by 2035 compared to today’s level. In October 2024, this government brought in the LDES cap and floor investment support scheme to deliver new LDES capacity. The scheme is being delivered by Ofgem and is technology neutral (and so could support a number of LDES technologies, including those referenced in the questions). Ofgem plans to consult this spring on the LDES projects it is minded to grant a cap and floor scheme to from its first LDES allocation round.