UK homes could save £14.2bn a year from solar roofs

A new analysis of more than 15 million UK rooftops says the average home could save £946 a year with solar and battery storage, as GreenSketch launches a free AI tool for homeowners. The report argues Britain’s grey-skies reputation is masking a major residential energy-saving opportunity.

Why it matters: - UK households could be missing out on a collective £14.2 billion a year in potential energy bill savings from rooftop solar and battery storage. - The report frames the roof as a financial asset, not just a maintenance cost. - The analysis suggests solar savings are meaningful across all four UK nations, not just in the sunniest regions.

What happened: - GreenSketch released the UK Rooftop Valuation Report on September 22, 2026. - The analysis covered more than 15 million individual rooftops across England, Scotland, Wales and Northern Ireland. - The average home analysed could save £946 a year from an optimised solar and battery system. - GreenSketch also launched Emily, a free AI agent available through its consumer platform EnergyBrain. - Homeowners can enter their address on EnergyBrain to get an initial estimate of solar generation, storage, annual savings, investment and payback period. - The company says homeowners can also connect with installers after the initial estimate to refine design and get a quote.

The details: - GreenSketch used proprietary AI to model projected financial performance for solar and battery systems at more than 15 million addresses. - The analysis modeled each rooftop individually instead of using regional averages. - The report paired solar with battery storage to estimate both household savings and the total value of the UK residential rooftop opportunity. - Southern regions delivered the highest average annual savings, including South West Wales at £1,001 and South East England at £991. - In Northern Ireland, the strongest returns were clustered in the east rather than the south. - The report says solar panels generate electricity from daylight, not constant direct sunshine. - Batteries let households store daytime electricity for later use. - Small plug-in solar systems have just become legal for consumers to buy and install, which GreenSketch expects will increase familiarity with home generation. - GreenSketch says its platform factors in roof characteristics and local solar generation when producing estimates. - GreenSketch is developed by OSW Group, one of Australia’s largest solar distributors. - The platform is already used by more than 4,000 solar installers globally. - The report was developed in collaboration with Tongwei and Fox ESS.

Between the lines: - The report challenges the common UK assumption that solar does not work well in a grey climate. - The geographic spread of savings suggests local weather and roof conditions can matter as much as latitude. - The pitch is aimed at homeowners who already spend heavily on renovations and may not think of rooftops as income-producing assets. - The launch of Emily is designed to move homeowners from broad interest to a roof-specific buying decision. - The report also positions solar and storage as a way to future-proof homes for a more electrified energy system.

What's next: - GreenSketch is encouraging homeowners to check their own roofs through EnergyBrain. - The initial estimate can be used as a starting point before contacting installers for a final design and quote. - GreenSketch expects the UK launch of Emily to help more households evaluate solar and battery projects with clearer cost and savings expectations. - Tongwei and Fox ESS say the collaboration is meant to expand access to higher-value solar and storage solutions across the UK and Europe.

The bottom line: - GreenSketch is trying to turn rooftop solar from a niche sustainability choice into a mainstream home-improvement calculation, with real savings attached to every address.