⚡ Battery Retrofit

Can I Add a Battery to My Existing Solar Panels?

Yes — AC-coupled batteries retrofit to any existing system, your FiT payments are safe, and retrofits to existing solar sit within the 0% VAT treatment until March 2027.

✓ Free check✓ No obligation✓ One installer only
Facts checked against official GOV.UK sources — 27 August 2026

Two pathways

✓ If you qualify

Follow the funded route before the deadline.

Check my setup →
If you don’t

WH:LG, BUS, 0% VAT and one matched installer.

Check My Home →

AC vs DC coupling for retrofits

AC-coupled (battery has its own inverter) is the retrofit default: no rewiring of your array, works with any brand or age of system, £3,500–£6,000 installed for 5–10kWh usable. DC-coupled only makes sense if your inverter is due replacement anyway — a hybrid inverter + battery swap can be cheaper combined.

FiT and export safety

Feed-in Tariff payments are unaffected by adding storage — generation payments continue and deemed export isn’t metered down. On SEG, a battery lets you shift export into peak-price windows instead.

Sizing the retrofit

Match usable capacity to your evening consumption and summer surplus — the sizing guide has the tables. Most 4kWp homes land at 5–8kWh usable.

Frequently asked questions

Will it void my solar warranty?+
Is the VAT really 0%?+
How long does installation take?+
Sources & MethodologyVerified 27 Aug 2026

Facts checked 21 August 2026. We link to official sources and show when facts were last verified. If a scheme changes, we update the page.

Check what your home qualifies for

Free, independent, 60 seconds. We compare every option, check Government scheme eligibility and match you with one trusted local installer if you want one.

Check My Home →