• Report finds over 90% of suitable commercial roofspace remains unused for solar, despite a clear financial case for landlords and tenants.

A report commissioned by Real Estate:UK, in partnership with Forsters and Push Power Ltd and authored by Cushman & Wakefield, has found that untapped UK commercial rooftops could generate 60 gigawatts of solar capacity, enough to power around 20 million homes a year. The findings were published on 9 September 2026.

The research, drawing on data from 70 real estate organisations with a combined AUM of more than £500bn, found that less than 10% of suitable commercial roofspace is currently used for solar, providing just 3 to 5GW of capacity. The remaining potential is equivalent to almost 20 Hinkley Point C nuclear power stations, and more than ten times the AI data-centre capacity the Government expects the UK to need by 2030.

The report sets out a strong commercial case for rooftop solar. A typical 300kWp installation costing £250,000 could deliver a 20% net yield in its first year and a 5.5-year payback if tenant-funded, or a 12% net yield and eight-year payback if landlord-funded. Both models would save 53 tonnes of CO2e annually.

Despite this, 85% of respondents expect rooftop solar activity to increase, though the report warns this depends on policy reform. Barriers include financial viability, REIT regime ambiguity, insurance terms, leasing complexity and grid connection delays.

The report makes seven policy recommendations, including clarifying REIT rules for solar investment, standardising legal and commercial frameworks, introducing consistent insurance standards, strengthening export revenue certainty, accelerating grid reform, providing long-term policy certainty on MEES, and raising the 50kW cap on permitted development for solar schemes.

Rob Wall, assistant director at Real Estate:UK, said: "Solar energy has a critical role to play in the UK's energy transition, and commercial real estate has the potential to be a major player in the generation of rooftop solar. However, as our research shows, deployment of solar on commercial buildings is slow and we are still some way off from delivering that long promised rooftop revolution. There is ambition, with 85% of real estate professionals expecting solar power generation from commercial buildings to increase over the next 24 months, but for that to happen we need a series of policy reforms as set out in today's report."