What does a solar battery do?
A solar battery stores electricity your panels generate during the day that you are not using at that moment. Instead of exporting it to the grid, you use it in the evening and overnight, which reduces how much electricity you need to buy from your supplier.
The battery charges and discharges automatically. Most systems come with an app that shows how much you have generated, stored and used.
Do I need a battery with solar panels?
No, but it often helps. Without a battery, many homes use only part of their solar electricity directly because nobody is in during the day. A battery lets you use more of what you generate. Whether it is worthwhile depends on your routine, your usage and your tariff.
- A good fit if you are out during the day and use most electricity in the evening.
- Useful if you have, or plan to get, an electric car or a time-of-use tariff.
- Less important if someone is home all day and already uses most of the solar output.
What size battery does a Scottish home need?
Many homes are well served by a battery of roughly 5 to 10 kWh of usable capacity. The right size depends on your evening and overnight electricity use and the size of your solar system. A battery much larger than you can regularly fill or empty adds cost without adding much benefit.
In summer a well-sized battery may fill from solar most days. In winter it will rarely fill from panels alone, which is where cheaper overnight charging comes in.
Can a battery charge from the grid on a cheaper tariff?
Yes. Many batteries can charge from the grid overnight on a time-of-use tariff and then power your home during more expensive hours. This is especially useful in Scottish winters, when solar generation is low but the battery can still be put to work every day.
How much does a solar battery cost?
A home battery typically costs around £3,000 to £6,000 installed, depending on capacity, brand and whether it is fitted alongside new panels or added later (typical, subject to survey). Batteries installed in homes currently qualify for 0% VAT until 31 March 2027.
Fitting a battery at the same time as your panels is usually the most cost-effective approach, because one visit covers the electrical work for both.
Can I add a battery to my existing solar panels?
Usually, yes. An AC-coupled battery can be added to most existing systems without replacing the panels. If your current inverter is near the end of its life, a hybrid inverter that manages both panels and battery may be the better choice. We check this during the survey.