A standard 4kWp solar system in the UK costs between £6,500 and £8,500 fully installed — panels, inverter, mounting and all electrical work included. Add battery storage and the total is typically £10,000–£14,000. Smaller 3kWp systems start from around £5,500. Thanks to the current 0% VAT rate (until March 2027), you’re saving up to £2,850 versus paying standard-rate VAT. Cost per installed kWp currently sits at around £1,500–£2,000 across the UK.

The Smart Export Guarantee (SEG) is a UK government scheme that requires all licensed energy suppliers with 150,000 or more customers to pay you for every unit of surplus solar electricity you export to the national grid. Rates range from 4p to 15p per kWh depending on your supplier and tariff — it genuinely pays to shop around. To qualify, you need an MCS-certified solar installation and a smart meter. An average 4kWp household earns around £100–£200 per year from SEG, on top of direct bill savings.

Several things are running right now. The 0% VAT rate is universal — any residential solar installation in Great Britain qualifies until March 2027. The Warm Homes: Local Grant offers up to £15,000 for homes with EPC ratings D–G. In Scotland, Home Energy Scotland grants of up to £7,500 are available. The Warm Homes Plan, launched January 2026, will offer 0% interest loans for all homeowners when fully operational in 2027. ECO4 (which provided free solar for lower-income households) ended in March 2026, but its successor schemes continue its work at a larger scale.

Yes — and this is the question we get asked most. Panels generate electricity from daylight, not just direct sunshine, so overcast days still produce useful power. The UK receives between 1,100 and 1,600 sunshine hours per year depending on location — Cornwall gets the most, Scotland the least, but both are sufficient for a solid solar investment. A typical 4kWp system in central England generates around 3,500–4,200 kWh per year. Solar panels in Yorkshire will generate meaningfully less than in Devon, but both make financial sense at current electricity prices.

For most 3–4 bedroom UK homes, a 4kWp system of 8–10 panels is the right starting point. Smaller homes or lower-consumption households suit 3kWp. Larger properties, EV owners or those with a heat pump should look at 5–6kWp. The simplest way to size it: find your annual kWh consumption on your electricity bill and aim for a system that covers 60–80% of your demand. We’re happy to help you work this out — just drop us a message at support@solarbriton.co.uk and we’ll give you a straight answer.