Solar Panels and Battery Cost UK: Is Home Storage Worth It?

These are typical fitted prices for UK homes in 2026, for straightforward installations:

• 4kW solar only: £6,000 to £8,000
• 4kW solar with a 5kWh battery: £9,000 to £11,500
• 5 to 6kW solar with a 10kWh battery: £11,000 to £14,000
• Larger systems with 13kWh or more of storage: £14,000 and upwards

Battery prices for homes commonly work out at around £700 to £1,100 per kWh of capacity fitted, with larger batteries cheaper per kWh. Installing solar and a battery together usually costs less than adding a battery later, because the scaffolding, electrical work and certification are done once, and a single hybrid inverter can run both.

Prices depend on the battery's capacity, its brand, whether it needs its own inverter, where it will be installed and whether your consumer unit needs upgrading.

Always compare batteries on usable capacity rather than nominal capacity. A battery sold as 10kWh may only allow you to use 9kWh or so, and two batteries with the same headline figure can deliver different amounts of usable energy every day.

A battery saves money in two main ways, and most households benefit from a combination of both:

• Storing solar surplus: without a battery, most homes use around 30% to 50% of their solar output directly and export the rest. A battery stores midday surplus for the evening, raising self-consumption to around 60% to 80% for many households. Each stored unit saves the difference between your import price, an average of 26.32p per kWh under the price cap from 1 October 2026, and your export rate.
• Charging cheaply from the grid: on a time-of-use tariff, a battery can charge overnight at a low rate and power the home during expensive hours. This works all year, including winter, when solar surplus is small.

Some tariffs also pay higher export rates in the early evening peak, typically around 4pm to 7pm. A battery can hold solar or cheap overnight electricity and export it during that window, which can add useful income for households that manage it well.

Battery sales projections often assume the battery fills with solar every day of the year. In reality, a UK solar system generates roughly a quarter as much in December as in June, and in winter most homes use all their solar output as it is generated. There is often little or no surplus to store from November to February.

That means a battery bought purely to store solar sits largely idle for a third of the year. Its summer savings are real, but they are smaller than a year-round calculation suggests.

The battery's winter value usually comes from the grid instead. On a time-of-use tariff with a cheap overnight rate, a battery can charge at night and cover the expensive daytime and evening hours, saving money every day of the year whether the sun shines or not.

For many households, that tariff saving is worth as much as the solar storage. A battery on a standard single-rate tariff loses that option entirely, which is one of the most common reasons battery payback disappoints. Before buying, check that a suitable time-of-use tariff is available to you and that the battery's software can use it automatically.

Take a household with a 4kW solar system that adds a 5kWh battery for around £4,500. Assume an import price of 26.32p, an export rate of 12p and a cheap overnight rate of around 7p on a time-of-use tariff.

• Solar storage: on around 250 days of the year, the battery stores about 4 kWh of solar surplus that would otherwise be exported. Each unit is worth about 14p more used at home than exported, so that is about £140 a year.
• Overnight charging in winter: on around 115 days when solar surplus is small, the battery charges overnight and covers about 4.5 kWh of expensive use. After charging losses, each unit saves around 18p, adding about £95 a year.

Together that is about £235 a year, a simple payback of around 19 years on the battery alone. With a poor export rate of around 4p, each stored solar unit is worth more and the saving rises to around £320 a year, a payback of about 14 years.

Households with higher evening use, an electric car or a tariff paying high peak export rates can see much better returns. These figures are illustrative, but show why a battery is a considered purchase rather than an automatic add-on.

A battery tends to make strong sense for households that:

• Are out during the day and use most of their electricity in the evening, so much of their solar output would otherwise be exported
• Have a poor export tariff, which makes storing solar for later more valuable than exporting it
• Are on a time-of-use tariff with a cheap overnight rate and, ideally, a higher peak export rate
• Have an electric car and a tariff designed around off-peak charging
• Use a lot of electricity, for example with a heat pump or electric heating
• Want backup power during cuts, where the system is designed for it

A battery tends to make weak sense for households that are at home during the day and already use most of their solar output, are on a standard single-rate tariff with no plans to change, or have a small solar system that rarely produces a surplus.

If you are unsure, choosing a hybrid or battery-ready inverter lets you add storage later. You can then use a year of real generation and usage data to decide whether a battery is worthwhile.

Size a home battery to the electricity you use in the evening and overnight, not to the size of your solar panels. A battery that fills and empties most days earns far more per kWh than a larger one that is rarely full.

As a rough guide:

• Smaller homes and lower evening use: around 4 to 6 kWh
• Typical family homes: around 5 to 10 kWh
• Homes with an electric car, heat pump or high evening use: 10 to 15 kWh or more

If you have a smart meter, check how much electricity you use between about 5pm and midnight on a typical day. That figure is a good starting point for battery size. If you plan to charge from a cheap overnight tariff, you may also want enough capacity to cover the expensive daytime hours.

Power rating matters as well as capacity. A battery's kW rating limits how much it can supply at once, so a battery with a low output may not cover a kettle, oven and washing machine running together, meaning some electricity still comes from the grid.

Most home batteries installed in the UK now use lithium iron phosphate (LFP) chemistry, which offers a long cycle life and good safety. Brands commonly installed include GivEnergy, Tesla Powerwall, Fox ESS, SolaX, Sigenergy and BYD, among others.

When comparing batteries, check:

• Usable capacity: the energy you can actually use each day.
• Warranty term: 10 years is common, and some brands offer 12 to 15 years.
• End-of-warranty capacity: a guarantee of 80% of original capacity is stronger than one of 70%.
• Cycle rating: many LFP batteries are rated for around 6,000 cycles or more, which suggests a working life of well over a decade at one cycle a day.
• Throughput limits: some warranties end once a set amount of energy has passed through the battery.
• Software and tariff support: whether the battery can automatically follow time-of-use tariffs.

Capacity declines gradually with use, so expect slightly lower savings in later years.

Where a battery goes affects cost, safety and convenience. Common locations include a garage, utility room, loft, under-stairs cupboard or an outside wall. Your installer should follow the manufacturer's rules on temperature, ventilation, clearances and fire safety, and explain why a particular location suits your home.

Points to check:

• Temperature: batteries perform best in a moderate, frost-free space. Cold lofts and hot spaces can reduce performance or limit warranty cover.
• Escape routes: batteries should not obstruct exits or be installed in places that would hinder escape in a fire.
• Cable runs: a long distance from the consumer unit or inverter adds cost.
• Noise: some systems have fans that are audible in quiet rooms.
• Grid notification: adding a battery that can export may change the network operator notification or application needed for your home.

Tell your home insurer about solar panels and battery storage. Most insurers are comfortable with properly installed systems, but they may want to know, and failing to tell them could cause problems with a claim.

Adding a battery at the same time as solar usually costs less overall, because a single hybrid inverter can run both and the electrical work and certification happen once. It also means you start benefiting from storage straight away.

Adding a battery later has its own advantages:

• You can use a year of real generation and smart meter data to decide whether a battery is worthwhile and what size you need
• Battery prices have generally fallen over time
• You spread the cost

If you are undecided, ask for a hybrid or battery-ready inverter in your solar quote. It may cost slightly more than a basic inverter, but it makes adding storage later simpler and cheaper. An AC-coupled battery, with its own inverter, can also be added to almost any existing system, though usually at a higher cost.

Whichever you choose, ask installers to show the payback of solar alone and of solar with storage, using your own usage data and the tariff you would actually use. That makes the value of the battery clear rather than bundled into the overall figure.

To compare solar and battery quotes fairly, give each installer the same information about your home and household, and ask each of them for the same breakdown of costs and savings:

1. Your annual electricity use and, if possible, smart meter data showing evening use
2. Your current tariff, and whether you would consider a time-of-use tariff
3. Any plans for an electric car or heat pump
4. Where a battery could be located
5. Whether backup power during cuts matters to you

When quotes arrive, check the usable battery capacity, the price per kWh of usable capacity, the warranty and end-of-warranty capacity, and the payback with and without the battery. Be wary of projections that assume the battery fills with solar every day of the year.

Our home solar page explains the main system options, including solar and battery packages. When you are ready, compare quotes from up to three MCS-certified installers for solar, storage or both.