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Which tariff is cheapest with solar?

Put in the tariffs you're weighing up. We work out your bill with and without a plug-in kit.

1Your home

Yearly electricity use 3,323 kWh

3,323 kWh is the GB average DESNZ uses. Your bill or supplier app shows yours.

Kit panel size 890 Wp

Most kits are 800–1,000 Wp.

2The tariffs you’re weighing up

Enter the rates from your supplier. We don’t list supplier tariffs.

Unit rate (p/kWh)

Standing charge (p/day)

Cheaper night rate (Economy 7 or similar)

Export rate (p/kWh)

Most plug-in kits get nothing for exports.

Unit rate (p/kWh)

Standing charge (p/day)

Cheaper night rate (Economy 7 or similar)

Export rate (p/kWh)

Most plug-in kits get nothing for exports.

Cheapest with solar: Price cap (single rate)

£941

a year, with the kit saving you £118

Yearly bill, before and after solar

Price cap (single rate)£941
£1,060 now · solar saves £118

853
kWh made: 467
kWh used at home: 386
kWh exported

Solar only offsets daytime use, so it saves most on tariffs with a high daytime rate. Output from PVGIS for West Midlands; the price cap row uses Ofgem’s cap for your region. How tariffs and plug-in solar interact.

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