Key takeaways: Solar panel cost UK: A fully installed home system costs £5,000–£9,000 in 2026; the 4 kW sweet spot for a typical 3-bed home is £6,000–£8,000. 0% VAT applies to the whole installation (panels and batteries) until 31 March 2027, when it reverts to 5%. Battery add-ons run £2,500–£6,000 by size, and about 94% […]