Solar Battery Cost UK (2026)
Last updated 5 October 2026 · Prices based on the Ofgem price cap (October 2026 – December 2026)
A battery stores surplus solar electricity for the evening, or charges cheaply overnight to avoid peak rates. It doesn't generate energy itself, so savings depend entirely on the price gap between when you charge and when you use.
Solar battery payback calculator
At £4,500 net cost and £320 saved a year, it pays for itself in about 14.1 years.
- Net cost
- £4,500
- Payback
- 14.1 yrs
- 10-year saving
- £-1,300
Simple payback = (cost − grant) ÷ annual saving, at today's price cap (26.32p electricity, 7.97p gas). Ignores future price changes.
Solar battery costs by capacity
| Capacity | Typical installed cost | Typical annual saving |
|---|---|---|
| 5kWh | £3,000–£4,000 | £180–£260 |
| 10kWh | £4,500–£6,000 | £280–£420 |
| 13.5kWh | £6,500–£8,500 | £350–£480 |
| Retrofit labour (existing solar) | +£500–£1,000 | — |
What affects the cost
Capacity
Match to your evening use, typically 5–10kWh.
Tariff
Time-of-use tariffs boost battery savings.
Hybrid inverter
Fitting with new solar avoids a second inverter.
Warranty
Look for 10 years and a guaranteed cycle count.
How to reduce the cost
- Fit at the same time as solar panels
- Pair with an off-peak tariff
- Size by your evening use, not your roof
- Check the battery's usable capacity, not just total
Frequently asked questions
Is a solar battery worth it in the UK?
If you're out during the day or have a time-of-use tariff, often yes. Payback is typically 10–15 years.
How long do home batteries last?
Most are warranted for 10 years or 6,000+ cycles.
Is there VAT on batteries?
Batteries installed in homes are zero-rated for VAT until March 2027.
Sources and methodology
Energy prices come from the Ofgem price cap for Direct Debit customers (GB average). Installation costs are typical UK ranges from installer quotes and industry guidance, rounded. Savings use today's rates and do not predict future prices.