As an extreme heatwave hits, UK homes with solar panels power equivalent of five hours of ‘free’ daily air con use

Rooftop solar installations boom in UK, hitting new generation records

The UK’s need for household cooling is accelerating, as heatwaves become a fixture of British summers. At the same time, rooftop solar is experiencing a boom in the wake of the second energy crisis in four years.

Homes are currently installing rooftop solar at the fastest ever annual rate. Over 2.5 GW of solar was installed in both 2024 and 2025, whereas 2.5 GW in total was installed in the five years from 2017 and 2021. This is happening without government subsidies for rooftop installations, unlike the UK’s first solar development boom from 2010-2016, which was supported by the now-closed Feed-in Tariff and Renewables Obligation subsidies.

A large number of solar farms are also in development, supported by the government Contracts for Difference scheme. Although just 854 MW of solar is installed through the scheme so far, 10,343 MW is also contracted to be built before the early 2030s.

This surge of installations has led to a huge increase in solar generation, with new records being broken frequently. The peak solar power half-hourly generation record was broken eleven times in the first half of 2026 alone. Britain also set a new all-time monthly solar generation record in May, beating the previous all-time record in May the previous year.

Air con use in the summer can benefit the grid and consumers

The UK grid can benefit from increased demand for air conditioning at high solar generation hours. A new service, the ‘Demand Flexibility Service’ is to be used to reward consumers for increasing electricity use during these periods.

Even for households without rooftop solar, flexibility payments mean a wider pool of consumers can benefit by increasing demand during reward periods, including through the use of air conditioning.

“More and more households are seeing the benefit of rising solar across the UK,” continued Frankie Mayo, “Plug-in balcony solar will make the technology more accessible, and at peak hours in the summer, households even without solar panels could be rewarded for using more electricity.”