A solar battery stores the electricity your panels produce during the day so you can use it in the evening, instead of exporting it to the grid for a fraction of what you pay to buy it back. In the UK, a typical home battery storage system of 5–10 kWh costs around £4,000 to £6,500 installed, with larger 13 kWh-plus systems reaching £8,000–£10,000, and eligible residential batteries currently benefit from 0% VAT – even when added to an existing solar system.
The main attraction is bigger savings on electricity bills. A battery can push the share of solar power you use yourself from roughly a third to well over half, and on a time-of-use tariff it can also charge overnight at cheap rates and power your home through the expensive evening peak – useful even in winter when the panels produce less.
This guide compares solar battery prices by capacity, how to choose the right battery size, realistic savings and payback periods, the best-known battery options on the UK market and what to check before adding storage to your home.
Solar battery prices by capacity
Battery storage is priced mainly by usable capacity in kilowatt-hours (kWh). The Energy Saving Trust puts typical battery systems at £5,000–£8,000, and the cost per kWh generally falls as capacity rises.
Installed prices include the battery, any inverter or gateway it needs, wiring and labour. Fitting a battery at the same time as solar panels is usually cheaper than a retrofit, because the installer can use a single hybrid inverter and one visit.
How big a battery do you need?
A battery only saves money when it is regularly filled and emptied, so bigger is not automatically better. A good starting point is to size it to cover your evening and overnight electricity use:
- Check your bills or smart meter app for your average daily usage. A typical UK home uses roughly 8–10 kWh a day.
- Estimate how much is used after dark. For many households this is around half of the daily total.
- Match the battery to your solar surplus. A 4 kWp system on a sunny day can easily produce more than you use, but in winter there may be little left to store.
- Plan for future demand. An electric car or heat pump changes the maths, so modular batteries that can be expanded later are worth considering.
For most three-bedroom homes, 5–10 kWh is the sweet spot. Larger batteries make most sense when combined with a time-of-use tariff, a big solar array or high evening demand.
How much can a solar battery save?
Savings come from two sources, and the best results combine both:
Depending on usage and tariff, a battery typically adds a few hundred pounds a year to the savings from solar panels. Because the upfront cost is significant, payback commonly falls in the region of 10 to 15 years – shorter for households that make full use of tariff shifting, longer for low-usage homes. Most batteries carry a 10-year warranty, so it is worth running the numbers carefully with your installer.
Popular solar battery options in the UK
The right battery depends on your existing inverter, space and budget. These are some of the most widely installed options:
| Battery | Capacity | Key strength |
|---|---|---|
| Tesla Powerwall 3 | 13.5 kWh | Built-in solar inverter, strong app, large single unit |
| GivEnergy | 2.6–13.5 kWh | UK-based, modular and widely supported by installers |
| Fox ESS | Modular stacks | Competitive pricing, easy to expand |
| SolarEdge Home Battery | Modular units | Best fit for homes with SolarEdge inverters |
| Enphase IQ Battery | 5 kWh modules | Designed for Enphase microinverter systems |
| Huawei LUNA2000 | 5–15 kWh | Modular, pairs with Huawei hybrid inverters |
Whichever brand you choose, look for lithium iron phosphate (LFP) chemistry, which is known for long life and good safety, plus a warranty that guarantees a minimum remaining capacity after 10 years.
What to check before you buy
- AC or DC coupled: DC (hybrid) systems suit new installations; AC-coupled batteries are usually simpler to add to an existing solar system.
- Backup power: most batteries do not keep the lights on during a power cut unless fitted with a backup or “EPS” function – ask if this matters to you.
- Location: batteries are usually installed in a garage, utility room or on an external wall, away from bedrooms and with good ventilation.
- Installer credentials: choose an MCS-certified installer; it protects your warranty, VAT relief and Smart Export Guarantee eligibility.
- Smart tariff compatibility: check the battery can be programmed for your chosen time-of-use tariff.
Frequently asked questions
Can I add a battery to my existing solar panels?
Yes. Most solar systems can be retrofitted with an AC-coupled battery or by replacing the inverter with a hybrid model. Retrofits currently also qualify for 0% VAT when they meet the eligibility rules.
Is a battery worth it without solar panels?
It can be, if you are on a time-of-use tariff with a large gap between night and peak rates. The battery charges cheaply overnight and supplies your home during expensive hours.
How long do home batteries last?
Most modern lithium batteries are warranted for around 10 years and many keep working beyond that, gradually holding a little less charge over time.
Are there grants for solar batteries?
There is no general UK grant for batteries, but 0% VAT reduces the cost, and some low-income households may receive batteries alongside solar panels through council-run schemes such as the Warm Homes: Local Grant in England.
Do I need permission to install a battery?
A battery inside your home or garage does not normally need planning permission. Your installer will handle notification to the local network operator.
Figures based on Energy Saving Trust data and typical UK installer prices.
Independent guide – not linked to any battery brand or installer.
