Solar Battery

A solar battery lets you store the electricity your panels generate during the day and use it when you actually need it — in the evening, on overcast days, or during a power cut. Without storage, a solar system exports a significant portion of what it generates to the grid, often at rates far lower than the electricity you buy back. In 2026, home battery storage has become a genuinely mainstream option for UK homeowners, with prices more accessible than ever.

The typical cost of a solar battery in the UK sits between £2,500 and £8,000 installed, depending on capacity, brand, and whether it’s added alongside new panels or retrofitted to an existing system. Installing a battery at the same time as your solar panels usually saves on shared labour and scaffolding costs.

Lithium Iron Phosphate (LFP) batteries are the standard choice for UK homes in 2026. They deliver over 6,000 charge cycles, a strong safety record, and a lifespan of 10–15 years. A 5kWh LFP battery — the most common size for a 2–3 bedroom home — costs around £3,500–£4,500 installed and typically stores enough solar energy to cover evening electricity use entirely.

For larger families or higher-consumption homes, a 9.5–10kWh system costs around £5,500–£7,000 installed. Premium options such as the Tesla Powerwall 3 (13.5kWh) sit at around £8,000+, offering smart app monitoring, automatic backup during power cuts, and seamless solar integration.

A 5–6kWh battery is the sweet spot for most UK households, increasing solar self-consumption from around 40% to 70–80% and saving an additional £200–£500 per year on top of savings from the panels alone. Combined with a time-of-use electricity tariff, a battery can also store cheap overnight grid electricity for use during the day.

At SolarBriton, we help you find the right size battery for your home and compare quotes from trusted MCS-certified installers.