- A solar battery costs start from £2,500, and they average around £5,000
- You should expect to pay around £900 per kWh of storage capacity
- The typical home will save approximately £582 each year from a solar-plus-storage system
If you’re always home during the day, when your solar panels produce the most electricity, using a solar storage battery to store electricity to use later is an excellent way to get more out of your solar panels.
Plus, it’ll help you cut your energy bills while helping to save the planet.
Another way to save money with storage batteries is by using them to store cheap off-peak electricity, and using that electricity during peak times.
In this guide, you’ll find out how much you’d pay for a solar battery, how it would affect your solar panel costs, and what else to consider before making your decision.
To find out how much a new solar-plus-storage system will cost you, just fill in this free form, and our expert installers will be in touch.
Want to get a better idea of how much a solar battery could save you if paired with solar panels? Head to our solar panel costs page to get a breakdown of figures.
How much does a solar battery storage system cost?
Currently, solar battery prices in the UK cost anywhere between £2,500 and £10,000 depending on the battery capacity, type of battery and lifespan.
A typical 5 kilowatt hour (kWh) solar battery, suitable for a three-bedroom house, costs £5,000, on average.
The amount you pay will depend on the amount of electricity the battery can store, also known as its capacity.
Prices start at around £2,500 for the smallest storage systems, those under 4kWh.
These will generally be able to hold the excess electricity created by a six-solar panel system – the one used by the average one or two-bedroom house.
As a rough guide, you should expect to pay £900 per kWh of storage capacity. The larger the solar PV system, the larger the battery you’ll need – and the lower the price you’ll pay per kWh.
Want to learn more about the price of solar panel systems? Head to our solar panel cost page.
How many solar batteries do I need?
You can have one or several solar batteries – the number will depend on the size of the batteries and also the size of your house.
This table gives a rough idea of the potential costs, but be sure to get at least three quotes from potential installers.
Remember, don’t buy more batteries than you need, otherwise you’ll pay for solar power you don’t use.
| House size | Peak power output (kWp) | Solar battery size | Cost of battery |
|---|---|---|---|
| 1-2 bedrooms | 2.1 kWp (6 panels) | 4 kWh | £2,500 |
| 3 bedrooms | 3.5 kWp (10 panels) | 5 kWh | £4,500 |
| 4+ bedrooms | 4.9 kWp (14 panels) | 10 kWh | £8,000 |
Which solar products are you interested in?
Get startedFactors that can influence solar battery price
Factors that can influence solar battery price include the type of battery it is, the capacity, the lifespan, installation, and the battery’s depth of discharge.
Type of battery
There are two main types of batteries – lithium-ion and lead-acid.
Lithium-ion solar batteries are the most mainstream and cost-effective type, and have the biggest market share.
They cost slightly more upfront than lead-acid batteries, but they’re more durable and have a longer lifespan.
Lead-acid batteries have cheaper upfront costs than lithium-ion ones, but they don’t perform as well over time, so they might end up costing you more in the long term since you might have to replace them sooner.
| Features | Lead-Acid Battery | Lithium-ion battery |
|---|---|---|
| Capacity | 4 kWh | 4 kWh |
| Average material cost (not including installation) | £2,000 | £4,000 |
| Average depth of discharge | 50% | 90% |
| Average life cycle | 1,800 | 4,000 |
| Cost per kWh, per cycle | £0.556 | £0.278 |
Capacity
Storage capacity refers to the total amount of energy your solar panel battery can store, while usable capacity refers to the amount a battery can discharge for use.
The amount of storage capacity and usable capacity is measured in kilowatt-hours (kWh), and in general, the greater the capacity, the higher the cost of the solar battery storage system.
In addition, the greater your energy use, the bigger capacity your solar panel battery should have.
Lifespan
Batteries with a larger number of cycles have a longer lifespan, but they can sometimes cost more upfront because of this.
A cycle refers to one full charge and discharge of the battery. The more times it can do this, the longer it will last.
Lithium-ion batteries tend to have twice as many cycles, and so twice the lifespan, of lead-acid batteries.
Installation cost
The installation cost of solar battery storage systems varies based on the size of battery you need, your location (some areas such as London are more pricey), and the layout of your property.
In general, it’s more economical to set up your solar battery system at the same time as you install your solar panels, rather than retrofitting one.
Depth of discharge
Depth of Discharge (DoD) means how much you can use the battery before recharging it.
Most solar batteries should not be run to 0% before recharging or the lifespan will be shortened significantly. The same principle applies to the batteries in our phones and laptops.
For example, if you buy a solar battery storage system that has a capacity of 5kW energy storage and 80% DoD, it should be charged when it reaches 4kW used. This will extend the life of the battery.
The higher the DoD, the more of the battery’s capacity is usable on a day-to-day basis.
Solar battery cost calculator
The bigger your house and the higher your energy usage, the higher capacity your solar battery will need. This may increase the cost of the system.
Check out our cost calculator for an estimate.
Advantages and disadvantages of solar batteries
Here are the main pros and cons of solar batteries.
Advantages
You’ll be much better protected from energy price rises, as nearly all of your electricity will come from solar power.
When you consider the big swings in electricity prices that we’ve seen over the last couple of years, that sounds like an excellent idea.
A three-bedroom property with a solar panel system and a 5kWh battery will save £582 per year on average, plus you’ll be less dependent on the grid for your energy.
A solar battery can also help you stop 28 tonnes of greenhouse gas emissions from entering the atmosphere over the lifetime of your solar array – one of the best ways to reduce your carbon footprint.
Some battery systems can also be configured to provide power during a power cut, though this will add to the cost.
Disadvantages
The typical initial cost of £4,500 is steep when you’ve already spent around £7,026 on solar panels, as the average three-bedroom house would.
It’s unlikely to save you money in itself, because the savings on your bills are unlikely to outweigh the cost of the battery.
That means it will push back the break-even point of your whole system by a further 10 years (26.66 years). And it will take up roughly the same amount of space as a washing machine or combi gas boiler.
And it may be pointless to get a battery if you already have an electric vehicle or are planning to get one that will be plugged in at home during the day, as you can just use your excess solar energy to recharge your car.
Additional solar battery costs
If you already have solar panels, you may have to purchase an additional inverter so you can get an AC (alternating current) battery, which is easier to fit into an existing system.
An inverter typically costs £800, and lasts for around 10 years. With any luck, you won’t have to replace it before you buy a new battery.
Lithium-ion batteries, the most popular type of solar battery among homeowners, require barely any upkeep – just a bit of light dusting, and the occasional check-up to make sure they’re still holding charge properly.
If you’re wondering which is the best model, check out our guide to the best solar batteries.
| Pros | Cons |
|---|---|
| Protect yourself from energy price rises | It typically costs £4,500 |
| Save an additional £132 per year, on top of usual solar panel savings | It takes up space in your home |
| Prevent 28 tonnes of greenhouse gas emissions | It won’t break even by itself |
| Never spend a power cut in the dark | Pointless if you have an electric vehicle |
| Make your home more saleable |
Are solar batteries worth it in the UK?
Solar batteries can significantly reduce your dependence on the grid – especially in the summer – meaning you won’t have to rely as much on an increasingly expensive, volatile supply.
You could save 28 tonnes of greenhouse gas emissions over your solar array’s lifespan – the same amount as four people’s annual emissions.
It’ll take you longer to break even on your solar panel and battery system, around 26 years compared to 15.66 years without a battery. The additional savings on your bills from adding a battery are unlikely to outweigh the cost of the battery since batteries only last 10-15 years.
If your main concerns are affording the upfront cost and breaking even as soon as possible on your solar setup, stick with solar panels alone.
And if you have an electric vehicle, don’t get a solar battery, as you already own a big battery to send all that extra solar power: your car (assuming that you use your car regularly and that it’s plugged in at home during the day).
You can learn more about this in our helpful guide Are Solar Batteries Worth it in the UK?
How big is your solar panel system, and how roughly much did it cost?
“We had a combined package of solar panels and solar batteries, with a capacity of 13.8 kilowatts (kW). The total cost was £14,500. The panels were about £5,000.”
Do your solar panels generate enough power to cover all your electricity needs?
“In June, which was sunny, we used solar for almost all our electricity needs, including the car and hot water. In July and August, we had to use some grid power overnight to charge the batteries because the weather wasn’t so good.”
Have you managed to break even on your solar panels?
“We won’t break even for a few years yet, but feel we have pre-bought our energy and are protected from the vagaries of the energy market.”
Kassy lives in North Yorkshire, and has owned solar panels and solar batteries since February 2023.
Which solar products are you interested in?
Get startedNext steps
By now, you’ve made up your mind on solar batteries.
The next step is to compare quotes on a solar PV system, whether it includes a battery or not.
Just complete this free form, and you can get free quotes from qualified installers. You’ll be taking advantage of solar power in no time.
Frequently asked questions
What happens to solar power when batteries are full?
Once your solar battery is full, it will stop storing electricity from your solar panels. However, rather than the excess electricity that your panels produce going to waste, it goes back to the grid.
If your battery is connected to the grid, and you’re part of the government’s Smart Export Guarantee (SEG), you’ll earn money from the excess electricity that you export.
Should I get a bigger battery than I need just in case?
You don’t need to get a bigger battery to cover your backs – unless your household uses more electricity than average. For example, you might need a bigger battery if you want to use your solar panels to power an electric car or a heat pump.
If you’re worried about eventually needing extra storage, you can opt for a scalable storage battery. These let you increase capacity by adding extra batteries to the unit, instead of having to replace the whole thing.
How many hours will a solar battery last?
If your electricity is cut off and your battery has a full charge, a 10-kilowatt battery can power your house for around 30 hours. But bear in mind that this will be shorter if you use more electricity , such as if you do multiple loads of laundry in a day.
