Solar panel battery storage

Solar batteries store the electricity generated by solar panels during the day so you can use it later. This stored energy could be used at night or during very cloudy days where your solar panels don’t generate enough electricity.

The size of the battery will depend on the make, model and what capacity you buy. However, a typical battery storage system is around 100cm x 60cm x 25cm. This is slightly taller and wider than a washing machine but not as deep.

This depends on the type and size of battery you buy. It can range from £1,500 to £10,000, but the cost for a 5kWh battery system is around £4,600.

You should be able to save money by installing battery storage at the same time as solar panels. As the installers are already on-site, they’d be able to integrate the panels with the battery as part of the same job.

A solar panel battery system is a great option for many homes.

By storing excess energy ready for you to use later, it can reduce your reliance on the grid, leading to cheaper energy bills. It also helps you use cleaner energy and improve your carbon footprint.

However, the upfront cost of batteries can make it unrealistic for some homes. You’ll also need space to install one. A battery’s lifespan is shorter than solar panels, so you’ll need to replace it before the panels.

Using stored energy is less efficient than using energy directly generated by solar panels, so you’ll lose some energy by comparison.

This can vary depending on what battery storage you buy and how you use it. The typical lifespan of a solar battery is about 10 to 12 years.

Remember to ask about any warranties or guarantees for your battery and its installation.

If your solar batter storage is full, there are a few things you can do depending on your needs.

You can export excess electricity generated by solar panels back to the grid. You can even be paid to do so through a Smart Export Guarantee (SEG) tariff. This can make having solar panels even more cost-effective. If you sign up to an SEG, you should get around £120 a year in Great Britain. In Northern Ireland, you can sign up to get Renewables Obligation Certificate (ROC) payments. This is around £110 a year.

Some batteries can divert excess electricity to charge electric vehicles (EVs) or other storage systems. This helps you make the most of the energy your solar panels produce.

Speak to your installer about what options you have.

As well as lowering your energy bills and generating clean energy, solar panels can help power other positive changes too.

Combining them with a smart time of use tariff means you can benefit from cheaper electricity during off-peak times. This makes batteries more cost-effective compared to just storing what your solar panels generate.

If you have a heat pump, you can help lower your running costs with solar panels. Likewise, you can charge up your EV at home for less.

Yes, in some cases you can. This is thanks to something called bidirectional charging, which lets an EV either draw or supply power to your home or the grid. But your EV battery and charger must have this capability for you to do this.

EV batteries are larger than home battery storage systems. So, you could increase your storage capacity by a significant amount if you have an EV on the drive.

You should speak to an experienced professional about installing a battery storage system. They’ll need to connect the battery to the existing solar panel system and other systems that need it.

Batteries can be installed in garages, on external walls or utility rooms, depending on which one you choose.

You can use MCS’ find a contractor tool to find a certified solar battery storage installer. We recommended getting at least three quotes to make sure you get the best value for your needs.

To get an idea of what system would be suitable for your home, use our solar panel calculator. 

Use the solar panel calculator