In 40 seconds
A typical UK home solar system costs roughly £5,500–£12,000 installed: a 4kW system is commonly £6,000–£8,000, a 5–6kW system £8,500–£11,500, and adding a battery pushes it to £9,500–£12,000. Solar is 0% VAT until 31 March 2027. Most homeowners earn from solar two ways: cutting their import bill and selling surplus power back through the Smart Export Guarantee (SEG). Whether it pays back well depends heavily on your roof orientation, your electricity use and your tariff — which is why the honest answer is always a range, and why installation should be done by an MCS-certified installer (required to register for SEG).
Most solar guidance is published by companies selling panels, so the savings numbers tend to be optimistic. The pages below give honest cost ranges, explain how the income side actually works, and help you judge whether solar suits your specific roof — before you take a single quote.