Overview
- Solar4Good's Solar Cost Index, published Thursday, shows many homeowners can now expect payback periods of about seven to 11 years for a typical 4kW rooftop system.
- A standard 4kW installation has fallen to roughly £5,000–£8,000 from about £9,000–£13,000 in 2014 while Ofgem’s July–September 2026 cap set electricity at 26.11p per kWh, strengthening the financial case for home generation.
- A 4kW array typically produces 3,400–3,600 kWh a year and delivers about £600–£800 in annual benefits from lower bills and Smart Export Guarantee payments, with some households exceeding £1,000 by using more power during daylight.
- Adding battery storage and combining solar with electric vehicles or heat pumps can lift self-consumption toward 70%, cutting the need to buy grid electricity and improving the household return on investment.
- Over a 25-year assumed system life, Solar4Good estimates lifetime savings of roughly £15,000–£25,000, though actual returns depend on roof orientation, installer costs, SEG rates, and future retail electricity prices.