What is Solar Battery Storage? A Complete Guide for 2025

When enquiring about a solar panel installation, you’ll often be asked whether you’d like to add battery storage to your system.

As it will command an additional cost to an already pricey job, it’s an easy option to reject. However, a solar battery can allow you to save additional costs in the long run and in some cases, help you to generate income from your solar panels.

In this article, we’ll explain what solar panel battery storage is, highlighting its financial and environmental benefits. 

What is Solar Battery Storage?

A solar battery will collect any excess energy produced by your solar panels, and store it. You can then use this electricity on cloudy days, when less sunlight is absorbed by your solar panels, or at night, when your solar panels are inactive.

Depending on the battery system you have in place, you may be able to use the stored energy during power outages. 

Having battery storage at hand essentially means that you won’t be letting any energy provided by your solar panels go to waste. It will further reduce your reliance on the grid, lowering your energy bills once more. 

How does solar battery storage work?

Your solar battery will come into its own during off-peak times, such as when you’re at work and the kids are at school. If your solar panels are producing more energy than what is being used, the battery will collect the excess, storing it in DC form. 

It will then store the electricity until your solar panels stop producing enough electricity to support your home. As mentioned, this will be at times when sunlight absorption is at its lowest. 

Using a battery inverter, the electricity stored by the battery will be converted into AC and discharged into your home. You won’t have to press any buttons or flick any switches, as the process will happen automatically. 

How Much Electricity Can a Solar Battery Store?

Solar battery systems are not one-size-fits-all, with different models having different storage capacity. Generally, a residential solar battery will have a capacity of 2.5 kWh to 15 kWh. If charged to full capacity, a 10 kWh battery could power a home’s appliances for between 12 to 36 hours. 

Batteries for commercial properties are understandably larger than those available for residential buildings. A commercial solar battery can reach capacities of up to 100 kWh.

How much electricity do solar panels produce?

Once again, the answer to this question depends on the size of your system. A standard 4kw solar system will produce an average of 8-10 kWh per day, potentially rising to 15 kWh on the sunniest days. A 5kw solar system can produce around 12 kWh per day.

A larger 10kw solar system can produce between 35 and 45 kWh per day. 

To put these numbers into context, an average four-bedroom household will consume between 12 and 16 kWh of electricity a day. These figures will fall during work and school days, and if you live in a smaller home with less appliances on the go. 

The Benefits of Having a Solar Battery

Investing in a battery to run alongside your solar panel system is hugely beneficial on a number of fronts. For a start, it can contribute to lowering your energy bills, saving you money for use on more exciting means. 

Saving money

As we’ve explained, your solar battery will distribute excess electricity into your home during times when your solar panels can’t. This will stop you from having to use electricity from the grid, which will increase your monthly energy bills. 

In fact, a home with a solar panel and battery system can save double the amount than a home with solar panels alone. In some households, the amount of money saved in a year can climb to £800. 

Earning money

It isn’t just saving money that makes batteries worthwhile, as they can even start generating income. This is because of the UK Government’s Smart Export Guarantee (SEG) scheme, which allows you to sell excess electricity back to the grid for money.

While you don’t always need a battery to access the scheme, having one installed will allow you to maximise the amount you earn. 

Future-proofing your home

Energy prices are always on the rise, with developments in the last half-decade seeing them increase to unimaginable heights. With a power storage system, like a solar battery, installed, you are essentially protecting yourself from future price rises. 

As you’ll be generating your own electricity and keeping it ticking along 24/7 with a battery, these rising prices won’t affect you a great deal.

Increasing the value of your home

Both solar panels and accompanying batteries are seen as highly desirable by property valuation experts. Having them installed will increase the value of your property if you come to sell it, as it’s a sign your home is fit for the future. 

Buyers are also becoming more conscious of renewable energy and the benefits it offers, making your home an attractive proposition. 

Environmentally friendly

Solar panels are already a great environmental investment, as they use renewable energy from the sun to power your home. Adding a battery into the setup will lower your carbon footprint further, as you’ll be further reducing your consumption of electricity from the grid. 

How Much Do Solar Batteries Cost?

If you already have a solar panel system in place, battery installation prices tend to start from around £3500-4000. However, they may rise depending on the size of the battery and the complexity of the installation. 

If the battery is installed at the same time as the solar panel system, the price will usually be lower. This is because you’ll already be paying the labour costs and the installation will be simpler. In this case, you can expect to pay around £2000 for the inclusion of a battery. Once again, the price will rise if you increase the capacity of the battery.