Battery Storage Savings Calculator

Already have solar? See how much more you could save by adding a battery.

What are you looking for?

Your Annual Solar Generation

From your generation meter or last FiT statement — total kWh generated per year.

kWh / year

~1,000 small~3,500 typical8,000+ large

Your Annual Electricity Usage

From your bill — shown as annual consumption or estimated annual usage in kWh.

kWh / year

~2,000 low~3,100 avg UK6,000+ high

Battery Size

We've highlighted our recommendation based on your usage. You can select any size.

Battery System

Your Current Tariff

Import rate (p/kWh)

Export / FiT rate (p/kWh)

Energy price inflation (UK long-run avg ~7%/yr)

7% / yr

0% (flat)7% typical15% high

Your Battery Results — 10 kWh

Indicative Cost

£—

supply & install · ex. VAT

Est. Annual Saving

£—

extra solar you keep

Est. Payback

— yrs

battery warranted 10 yrs

Self-consumption without battery —%

Self-consumption with battery —%

Annual generation—

Annual usage—

Currently exported (est.)— kWh/yr

Captured by battery— kWh/yr

Worth at import rate—

Remaining export (FiT still earned)— kWh

⚠️ Subject to site survey — or send us photos of your consumer unit, inverter, generation meter, and roof. 📱 WhatsApp photos to 07575 724231 →

30 Year Picture

30yr battery return

£—

savings at 7%/yr inflation

cost of doing nothing

£—

grid bills at 7%/yr rise

Right now every unit your panels generate after midday gets exported at 12p — but you buy it back that evening at 28p. That's a 16p gap on every kilowatt-hour. A battery closes that gap permanently. Over 30 years, as energy prices keep rising, that difference compounds into a significant sum — all from energy you're already generating for free.

⚡ You thought this was it? If we add an EV charger and switch you onto an EV tariff, it gets even better.

Add an EV charger as part of your installation and you can unlock a smart overnight tariff like Octopus Go — charging your battery at as little as 7p/kWh overnight, then discharging during peak hours. No EV yet? The savings on the battery alone make it worthwhile from day one.

Night rate (p/kWh) 7p

3p7p typical20p

Battery self-consumption saving+£—/yr

Battery overnight charge saving+£—/yr

Total annual saving with smart tariff £—/yr

Revised payback with smart tariff — yrs

💡 Add an EV charger as part of the installation and you can use an EV tariff — charging your battery and car overnight at 7p, that's 21p cheaper than your day rate. Every mile driven on home-charged electricity instead of a public point saves you money, and every unit of overnight electricity used is 21p cheaper than it would otherwise be.

Indicative estimates only. Prices based on Fusion Solar's standard installed rates, subject to site survey or photographic assessment. Self-consumption estimates use tiered logic based on generation-to-usage ratio. 30-year projections assume 0.5% annual battery degradation and selected inflation rate. Your existing FiT generation payments are unaffected by this installation. Muse Homes Ltd trading as Fusion Solar UK · MCS Accredited.