A battery for your home, with solar panels or without.
Most people who own solar panels have no battery and no idea they could fit one. Most people without panels have no idea a battery can work on its own. Either way it is usually a one-day job.
The thing nobody told you
If your solar panels went up more than a few years ago, they almost certainly came without a battery. Batteries were expensive then, and the old export tariffs made it sensible to sell your surplus rather than store it.
That has changed. Battery prices have fallen, export rates are lower than they used to be, and a new kind of electricity tariff has appeared that makes a battery useful even on a grey day in January.
The result is that thousands of houses across the North West have panels on the roof doing good work between ten and four, and then buying electricity at full price from teatime onwards. A battery closes that gap.
We fit them. We also fit them to new-build homes, which from March 2027 will be built with solar as standard and, under the current rules, no battery at all.
And it does not need new panels. It bolts onto what is already there.
Will it work with what I have got?
In almost every case, yes. The question is not whether, but how.
AC-coupled. The usual route for a retrofit. Your existing solar inverter stays exactly where it is, and we add a separate battery with its own inverter alongside. Nothing about your current system changes. This is what we recommend for most retrofits, because it is simpler, it leaves your existing kit alone, and it does not disturb any warranty or export arrangement you already have.
DC-coupled. We replace your existing inverter with a hybrid unit that handles both the panels and the battery. It is slightly more efficient, but it only makes sense if your current inverter is old or due for replacement anyway. If yours is ten years old and starting to throw error codes, this is worth a conversation. If it is five years old and working fine, it is not.
We will tell you which applies after we have seen your setup. A photo of your inverter and its label is usually enough to start.
No solar panels? A battery still works
What the new plug-in rules meanYou do not need solar panels to have a battery. Most people assume you do, which is why almost nobody asks.
On some tariffs, electricity overnight costs a fraction of the daytime price. A battery fills up in the small hours, when power is cheap, and then runs the house through the day. You end up buying most of your electricity at the overnight rate. It works in any season, because it was never relying on the sun.
It tends to suit homes that use a fair amount of electricity during the day, households already on an overnight tariff because of an electric car, and roofs that are wrong for panels.
The installation is the same as a retrofit: the battery is mounted in a garage, utility room or on an external wall, connected to your consumer unit, and registered with your network operator. It is not something to buy online and plug into a socket. Plug-in batteries are excluded from the rules that came in on 27 August 2026.
Battery storage installed on its own is zero-rated for VAT, the same as a battery added to solar, until 31 March 2027.
What the battery actually does
The same box earns its keep in two opposite ways, depending on whether you have panels. This section keeps them apart.
With panels. In the middle of the day your panels usually make more than the house is using, and the surplus goes to the grid for very little. At teatime, when the panels have stopped and the house is at its busiest, you buy electricity back at the full rate. A battery keeps your midday surplus for the evening instead. In winter, when there is little sun to store, it can also fill up overnight on a cheap off-peak rate. That is the seasonal extra, not the main job.
Without panels. The overnight rate does the whole job. The battery fills up in the small hours and runs the house through the day.
An illustration, not a promise. On some off-peak tariffs, electricity in the small hours costs a fraction of the daytime rate. A household that charges its battery overnight and uses that electricity during the day is buying it at the cheaper rate. Rates change often, so we check the current ones with you when we set the battery up.
What your household would actually save depends on your tariff, your usage pattern, your battery size and how you set it up. That is why we work it out for you, in writing, from your real bills, rather than putting a number on this page. Our trade body requires it, and it is the only figure worth having.
Most people who own solar have no idea this is possible. Now you do.
What it costs
Battery retrofits are priced mainly by capacity, and secondarily by whether any inverter work is needed.
Our retrofits typically land between £2,800 and £5,000 installed, at 0% VAT.
For context, market guides published this year put most UK home battery retrofits somewhere between roughly £3,500 and £8,500, with a 5kWh battery towards the lower end and 10kWh or more towards the upper.
On VAT. Battery storage has been zero-rated for VAT since 1 February 2024, including when it is added to an existing solar system or installed on its own with no solar at all. That relief is scheduled to end on 31 March 2027.
| Household | Usual range | Why |
|---|---|---|
| Smaller home, modest evening use | Around 5kWh | Covers evening and overnight for a couple |
| Typical family home | 8 to 10kWh | The common sweet spot for a house with existing solar |
| High use, EV or heat pump | 10kWh and above | Needed to make overnight charging worthwhile at scale |
We size from your actual consumption data, not from this table. A battery that is too small will not capture your surplus. One that is too big costs more and works no harder. We would rather sell you the right one than the biggest one.
The paperwork, handled
Adding a battery counts as a change to your grid connection, so your electricity network operator needs to know about it. For most home retrofits that is a notification after installation. For larger systems, or where your existing solar already uses most of your connection allowance, it can mean an application before we start.
We handle all of it. We will tell you which applies to you once we have seen your existing system, and we will not start work until it is sorted. Our full guide to how this works is here.
What happens on the day
Most retrofits are done in a single day.
The battery is mounted, usually in a garage, utility room or on an external wall. If AC-coupled, its inverter goes alongside. We connect it to your consumer unit, commission it, and set it up to work with your tariff. Then we show you the monitoring app and explain what you are looking at.
You will have power throughout apart from a short planned interruption for the electrical connection, which we agree with you in advance.
Questions people ask
Can I add a battery to solar panels I already have?
Yes, in almost all cases. The usual approach is an AC-coupled battery, which leaves your existing solar inverter alone and adds a separate battery inverter. Most retrofits are completed in a single day.
What does a battery retrofit cost?
Ours typically land between £2,800 and £5,000 installed, depending on capacity and whether any inverter work is needed. Market guides currently put most UK retrofits somewhere between around £3,500 and £8,500, with a 5kWh battery at the lower end and 10kWh and above at the upper.
AC-coupled or DC-coupled, and which do I need?
AC-coupled is the usual choice for a retrofit, because it works alongside your existing inverter with no need to replace it. DC-coupled means fitting a hybrid inverter that handles both solar and battery, which is more efficient but only worth the cost if your current inverter is old or due for replacement anyway. We will tell you which applies after looking at your setup.
Is it worth getting battery storage with solar?
It depends on how you use electricity. A battery helps most if you generate more during the day than you use, or if you are on a tariff with cheap off-peak rates you can charge from. It helps least if you are already using nearly everything you generate as you generate it.
How long will a 10kWh battery last, and what size do I need?
A 10kWh battery covers roughly a typical UK household's evening and overnight use, though that varies enormously with heating, EV charging and how many people are in. Sizing should follow your actual consumption data rather than a rule of thumb, which is what we look at during a survey.
Does adding a battery need DNO approval?
Usually yes, in some form. Adding storage is a change to your connection and must be notified to your distribution network operator, either as a G98 notification after the work or a G99 application beforehand, depending on capacity. We handle that paperwork as part of the job. Our full guide to G98 and G99 explains the thresholds.
Can I charge the battery cheaply overnight on an off-peak tariff?
Yes, and for a lot of households this is where the real saving sits. On a tariff with cheap overnight rates you can fill the battery when electricity is at its cheapest and run the house from it during the expensive part of the day, whatever the weather has done to your generation. It works with existing solar as well as new installations, which is why a retrofit can pay back faster than people expect.
What are the disadvantages of battery storage?
The main one is upfront cost, and payback depends heavily on your tariff and usage. Batteries also degrade over time, typically retaining a guaranteed percentage of capacity for a warranted number of years, and they take up space, usually in a garage, utility room or on an external wall. Anyone who tells you a battery always pays for itself is not looking at your numbers.
Find out in two photos
Send us a picture of your inverter and its label, and a photo of your consumer unit. We will tell you whether your system can take a battery, which type, and roughly what it would cost. No visit needed to find out.
Send a photo of your consumer unit and a recent electricity bill instead, and we will tell you whether a battery on its own makes sense for your house.
We reply to every enquiry within two working days.