8kW solar system cost in the UK (2026)
A large detached home or one running an EV and heat pump together, needs plenty of roof.
Installed cost (typical)
~£13,600
Generation
~7,488 kWh/year
Annual savings (typical)
~£1,498
Roof space needed
~56 m²
Typical payback
~9.1 years
VAT on install
0% (until 2027)
| Size | Installed cost | Generation/yr | Annual savings | Payback | Roof space |
|---|---|---|---|---|---|
| 3kW | ~£5,100 | ~2,808 kWh | ~£562 | ~9.1 yrs | ~21 m² |
| 4kW | ~£6,800 | ~3,744 kWh | ~£749 | ~9.1 yrs | ~28 m² |
| 5kW | ~£8,500 | ~4,680 kWh | ~£936 | ~9.1 yrs | ~35 m² |
| 6kW | ~£10,200 | ~5,616 kWh | ~£1,123 | ~9.1 yrs | ~42 m² |
| 8kW (this page) | ~£13,600 | ~7,488 kWh | ~£1,498 | ~9.1 yrs | ~56 m² |
Savings assume typical rates, ~50% self-consumption, and an average SEG export rate. Your numbers depend on your region and SEG tariff,run your own figures here.
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