Is it worth getting a solar storage battery with my solar panels?
18 February 2025 | OVO
Solar panels are a smart way to cut energy costs and reduce your carbon footprint. They provide clean, renewable energy, and can reduce your bills by 85%.1 Solar panels are also relatively easy to install, compared to wind turbines and hydro power.
If you’re interested in getting solar panels, you might also want to know how to store your solar energy, so you can use it another time – like at night. That’s where solar storage batteries come in. Read on to find out what they can do for your energy bills, and how they can help you go greener.
About solar storage batteries
Solar batteries are designed to work with solar panel systems. They allow you to store up your solar energy to use at another time. Depending on your home's energy demands and the size of your battery, you could store enough electricity to power your home for up to 10 hours.
How solar batteries work
Solar panels generate electricity when the sun shines, but without a battery, any unused power goes back to the grid. With a battery, you can store this energy and use it later—reducing waste and increasing savings.
You can also sell any spare energy you make to the grid through our Smart Export Guarantee (SEG) scheme.
The different kinds of solar batteries
There are many, but lithium-ion batteries are the best option for your home solar system. That’s because they’re reliable, compact, have a high storage capacity, and don’t need much maintenance. In fact, a typical lithium-ion battery will last for up to 10 years or more, and will generally come with a warranty of 10 to 12 years.2
The size of the solar battery you’ll need will depend on how many panels you have, the electricity they make, and how much energy your home uses. Battery sizes at OVO range from 2.6kWh to 10.36kWh. For help deciding which battery will work best for your home, you can book a free call with one of our solar experts.
Other important things to consider when choosing the right battery for you include the depth of discharge, as well as whether it’s compatible with an EV (if you have one).
The benefits of getting a solar battery
1. Lower electricity bills
One of the main reasons you might want a solar battery is to save money on your energy bills. By storing your solar energy, you’ll buy much less electricity from the grid, cutting your bills significantly In fact, pairing your solar panels with a battery could save you up to £1,300 off your electricity bills every year.1
OVO’s solar battery tariff add-on, Battery Boost, uses smart charging technology to help you save even more. It gives you exclusive rates of 10p per kWh to charge your solar battery from the grid, but when the grid is at its greenest.3 That’s 58% cheaper than your usual rate.4 It’s ideal for storing electricity to use when it’s too cloudy or dark to generate your own.
And if that’s not enough, we’ll even buy back any stored power you don’t use at your usual SEG export rate. Find out more about our SEG rates.
2. Less reliance on the National Grid
A solar battery can reduce your reliance on the National Grid, as more of your electricity will come from your stored solar energy. This protects you from price changes and power outages, as well as helping reduce your home’s carbon footprint.
3. Helps you go greener
Getting battery storage alongside your solar panels isn’t just good for your wallet. It can help you go greener, too. Your solar panels will generate solar energy in the day, storing it in your battery to use at times when your energy demand is higher – for example in the evenings. So, instead of drawing electricity from the grid at these times – which is the peak time for UK energy use – you can use the power you’ve made at home.
Solar batteries are also an important step on the path to a more flexible energy system in the UK. A flexible energy system means we can reduce the amount of energy the grid needs to provide at peak times, and store excess green energy to use at these times instead.
It’s not just larger scale battery projects that make a difference – home battery systems are also important when it comes to energy flexibility. They mean less energy needs to be created from carbon-intensive sources.
What to consider before getting a solar battery
1. Upfront cost
The biggest consideration when getting a solar battery is the initial cost. Prices start around £2,500 and can go beyond £10,000, depending on capacity. On average, you’ll pay about £900 per kWh of storage—and larger batteries cost more.
To make this investment more manageable, we offer a range of batteries from Fox ESS and GivEnergy to suit different budgets. We also offer 0% finance on GivEnergy batteries to help spread the cost.5
2. Battery lifetime
Like all batteries, solar batteries degrade over time and will eventually need replacing. However, with proper care, you can expect at least 10 years of reliable performance. Following the manufacturer’s guidelines will help keep your battery running efficiently for longer.
3. Finding the right space for your battery
While solar batteries are becoming more compact, they still need dedicated space. For example, our biggest Fox ESS battery is 71cm wide and 62.5cm high – roughly the same size as a large suitcase.
The ideal location for a battery is a well-ventilated area with a stable temperature, such as a utility room, garage, or loft.
Not sure where to put your battery? Our solar experts can help you find the best spot in your home.
Is a solar battery worth it?
Whether a solar battery is right for you depends on your energy usage and goals. While the upfront cost can be high, the long-term benefits are significant. A solar battery can reduce your electricity bills, increase energy independence, and lower your carbon footprint. Ultimately, you’ll be contributing towards a more flexible energy system for the future.
Get a solar and battery quote today
Get a quick solar package quote online. You’ll get a free home survey with one of our solar experts, who will assess your home’s energy needs and show you how much you could save.
Important information:
1 These annual energy savings are dependent on your property type and location, roof type, slope and size. If your roof is shaded or isn't south facing, figures are likely to be lower. We based the figure on the following: a) You have 12 (440W) solar panels and a 9.5 kWh battery installed b) You’re home all day with an annual electricity consumption of 2,700 kWh (Ofgem). You currently pay our Standard Variable Rate of 24.85p (correct at 1 January 2025) and will use 39% of what you generate c) You sign up for our exclusive SEG rate (20p kWh) for customers who purchase solar and a battery from us, and you sell back the remaining 61% of energy generated. You’ll get a more accurate savings estimation once we’ve surveyed your property.
2 If you purchase a battery with OVO, you will get a warranty of 10-12 years depending on which manufacturer you choose for your home.
3 OVO's smart tech aims to charge your battery when the grid has more renewable energy in it, at periods of lower demand. Meaning it’s less likely your battery will be charged by energy from fossil fuels.
4 Up to 58% saving based on OVO charging the customer's battery at the Battery Boost rate of 10p per kWh versus charging the battery at OVO's current standard standard variable electricity rate of 24.50p which is 58.34% higher. If you override the controls and charge the battery from the grid, you'll be charged your standard electricity unit rate.
5 Finance is subject to eligibility and terms, and a £500 deposit. OVO is a broker not a lender.