1 June 2026 · 5 min read
Solar Battery Storage Explained: Should You Add One?
Batteries transform the economics of solar. Here's how they work, what they cost and whether you should add one in 2026.
Without a battery, unused solar goes back to the grid for around 5–15p/kWh (via the Smart Export Guarantee). With a battery, you can use that same power in the evening at 27p+/kWh — often doubling your savings.
How they work
Excess daytime solar charges the battery. When the sun goes down or generation drops, the battery discharges to power your home. Modern hybrid inverters manage this automatically.
What size do you need?
- 5 kWh — average household, no EV.
- 10 kWh — larger household or EV owner.
- 15 kWh+ — high usage, off-peak tariff arbitrage.
Off-peak tariff arbitrage
Tariffs like Octopus Go and Intelligent Octopus let you charge your battery overnight at 7–9p/kWh and use that power during the day. A battery pays back faster if you combine solar with a smart tariff.
Brands we install
Tesla Powerwall, Growatt, GivEnergy and others. We recommend based on your usage pattern, not on what we have in stock.
Not sure which size to go for? Send us your last electricity bill and we'll model it.
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