A combination of policies affecting solar and storage projects in the UK could put £26 billion of investment at risk and result in higher energy bills, according to a letter from trade association Solar Energy UK to UK Energy Secretary Ed Miliband.
The letter, signed by 10 members of Solar UK, raises concerns over the impact of December's Clean Power 2030 Action Plan (CPAP) on the development of ground-mounted solar farms and battery energy storage systems (BESS) after 2030. The group argues that the CPAP will stifle investment and slow the deployment of both solar and storage technologies, hampering the UK's renewable energy goals.
“We believe that many of these projects will be needed to account for project attrition, to ensure competition in Contracts for Difference auctions, and in case other technologies prove slower to deliver or more expensive; we do not believe that these factors are accounted for in the NESO's advice or the Government's CPAP,” the letter states.
According to the letter, the UK's solar generation capacity was estimated at 20.2GW at the end of 2024. The CPAP outlines a target of 47GW of solar capacity in Great Britain by 2030, with additional smaller rooftop systems. However, deployment is expected to slow after 2030, with only an additional 22.4GW forecasted by 2035. BESS capacity is also expected to rise slowly, from around 5GW today to 27.1GW by 2035, with only 1.6GW of additional capacity expected beyond that.
The letter warns that developers working on projects with connections for 2031-2033 could be left with surplus projects that do not meet market needs. It also highlights concerns that the CPAP may repeat the mistakes of earlier forecasts by the National Energy System Operator (NESO) that would impose even more restrictive targets.
Solar Energy UK has called for an increase in the 2035 cap for solar connected to the transmission grid, set at 17GW, and for more flexibility for BESS projects. The group argues that the current trajectory risks poor outcomes for the industry, government targets, and consumers, potentially leading to higher CfD prices and increased energy bills.
The CPAP is expected to be replaced by the Strategic Spatial Energy Plan in late 2025. However, Solar Energy UK warns that the timeline leaves insufficient time for necessary consenting, procurement, and construction. “The current plan will therefore cause an investment hiatus now and a hiatus of projects connecting in the early 2030s,” the letter concludes. Despite these concerns, the industry remains optimistic about future collaboration with the government to support the growth of solar and storage in the UK.
