At midday on 23 April 2026, solar panels across Great Britain pushed out 15,420 MW, the most they have ever delivered at once. Sunlight alone was powering 42% of the whole grid.
The figure, equal to 15.42 GW, was logged through the Sheffield Solar PV_Live tracker and published by the SolarUK data platform. It beat the previous record of 14.0 GW, which stood from July 2025.
April turned out to be a month of firsts. Britain broke four records in 25 days. On 6 April solar reached 14.1 GW, and the next day it hit 14.4 GW. On 22 April the grid ran 98.8% zero-carbon. Then came the 15.42 GW peak the following day.
How much sun Britain gets
Records aside, the country is not a sunny one. SolarUK puts the national range at 2.2 to 3.2 peak sun hours a day, with Cornwall at the top end (about 3.2). London averages roughly 2.97, Manchester 2.61, Hartlepool 2.52 and Edinburgh 2.42. Glasgow comes in at 2.34 and Inverness at 2.18, the lowest of the cities listed.
Hartlepool, in the TS postcode area, receives about 920 kWh/m² a year. A 4kWp system there would generate around 3,226 kWh a year, SolarUK estimates, saving roughly £839 at 26p/kWh. Its calculator works from satellite irradiance data and applies a performance ratio of 0.80 to the system size.
Cost and timing for householders
Residential systems in the UK usually run to 4 to 6 kWp. In 2025 a 4kWp installation cost £6,000 to £9,000, with 0% VAT until April 2027. It produces 2,800 to 4,200 kWh a year depending on location, saves £730 to £1,095 annually and pays itself back in 7 to 12 years. Homes with solar sold for about 6.9% more in 2025.
The best months to buy are October to February. December and January each account for only 3.6 to 4.4% of annual output, so little generation is lost. Installers are 60 to 70% less busy than in summer, quotes run 10 to 15% lower, and slots open up within days. June to August, by contrast, often brings waits of 12 weeks or more nationwide.
Balcony systems
Plug-in balcony solar is on its way. The DESNZ Solar Roadmap of June 2025 committed to a safety review of systems under 800W. Professionally hard-wired versions are legal now, and fully plug-and-play units are expected to be permitted in 2026. An 800W system costs £450 to £966, with professional connection adding £150 to £300.
Germany has more than 435,000 registered balcony systems, and in the United States most states allow plug-in units up to 2kW. SolarUK argues that British irradiance is comparable to Germany’s, so the obstacle has been regulation rather than weather. It counts 8 to 12 million UK households as addressable, since 57% of residents have no roof access, and projects 1 to 2 million systems by 2030 once the rules change.
Sources
Sources
- Solar power in the United Kingdom – Wikipedia
- SolarUK — Live GB Solar & Postcode Calculator | Sun Hours
