A battery stores the sun you make at midday, so you can use it at night. That's the difference between saving money and also keeping your lights on in a cut. How much it's worth to you depends on why you want one, and increasingly, on your tariff.
What's the money case?
Batteries pay back fastest when paired with a time-of-use tariff. You charge from cheap overnight or midday solar power, then avoid the pricey peak-rate evening. That way, you also stop exporting power for pennies when you could use it yourself. On a flat rate, the savings are thinner.
What's the peace-of-mind case?
If power cuts are common or costly where you live, a backup-ready battery recharges itself every morning. That value is real, even when the savings on paper are only so-so. It's a big reason why solar-plus-battery is the fastest-growing setup in the UK.
The quick version
- Batteries shine on time-of-use tariffs and high evening prices.
- They double as self-recharging backup power.
- 0% VAT applies to batteries until 31 March 2027.