It is one of the questions we are asked most often at the moment. Someone has looked at their roof, decided solar is not for them — or not yet — and wants to know whether they can just have the battery. The short answer is yes, you can. Whether you should is a different question, and the honest answer depends almost entirely on your electricity tariff and how much power your home gets through.
How a battery saves you money with no solar attached
With solar panels, a battery stores electricity you have generated yourself, so you use it in the evening instead of selling it back for pennies and buying it again at full price. Take the panels away and the battery has nothing to store except electricity you have bought from the grid. The saving no longer comes from generating your own power. It comes from when you buy it.
Most UK suppliers now offer a tariff with a cheap overnight window, typically five to seven hours somewhere between about 11pm and 6am. The off-peak unit rate on those tariffs is often single-figure pence, against a standard rate in the mid-to-high twenties for the rest of the day. Your battery charges up overnight and then runs the house through the morning and evening peaks, when electricity is at its dearest. Nothing about how you live changes. You have simply shifted when the meter is ticking.
That is the entire business case, and it is worth being clear-eyed about it: you are not generating anything, you are buying the same units at a lower price. Tariffs and rates move around constantly, so check what is genuinely available on your meter before you commit to anything. Some of the cheapest overnight tariffs are aimed at EV drivers but accept households without one; others are open to anyone with a smart meter. If you do run an EV, our EV charging cost calculator shows what those overnight rates are worth against charging on the public network.
Who it genuinely suits
- Homes that use a lot of electricity. The bigger the nightly charge you can shift, the bigger the gap you are capturing. Heat pumps, electric heating, hot tubs and an EV all push you into this bracket.
- Roofs that cannot take solar. Flats, listed buildings, heavily shaded plots, north-facing roofs with no alternative pitch, or a roof covering that needs replacing first. A battery does not care what your roof looks like.
- People who want solar later. Fitting the battery first and adding panels down the line is perfectly workable, provided the system is specified with that in mind from the start.
- Households that want some resilience. If power cuts are a recurring nuisance where you live, a battery with the right inverter and switchgear can keep essentials running.
Who it does not suit — and we will tell you
If your household gets through something like 2,000 to 2,500 kWh a year, a battery on its own is a hard sell. The amount you can shift each night is small, so the annual saving is small, and the payback stretches out beyond the point where it makes much sense. We would rather say that at the survey stage than fit something that quietly disappoints you. For a lower-usage home, our guide to energy efficiency and reducing your energy bills is usually the better place to start.
The other trap is the tariff itself. Cheap overnight rates are usually paid for with a higher rate during the day. If you cannot move most of your consumption into the battery — because the battery is too small, or the house draws heavily through the afternoon — you can end up paying more overall than you would on a flat tariff. The sums only work if the battery is sized properly against your actual usage, not against a sales target.
What a battery on its own will not do
It will not earn you export payments. The Smart Export Guarantee pays for surplus renewable generation sent to the grid. A battery is storage, not a generation technology, and electricity you bought from the grid and pushed back out again is not eligible. A handful of suppliers run their own flexibility or export schemes that batteries can join, but read the terms carefully rather than assuming SEG-style income.
It will not make your electricity free, and it will not insulate you from price rises the way panels do, because you are still buying every unit you use. And while charging overnight often means drawing greener grid electricity, the carbon saving is modest compared with generating your own.
Backup during a power cut is not automatic
A lot of people assume any battery keeps the lights on when the street goes dark. It does not, unless it has been specified to. You need a backup-capable inverter and a changeover arrangement wired in at installation, and you need to decide in advance which circuits are worth keeping live. We have written this up in more detail in our guide to what happens to your system in a power cut.
What installing one actually involves
A surveyor comes out, looks at your consumer unit, your meter and your usage, and works out where the battery can sensibly live — a garage, a utility room, a plant space, sometimes an outside wall with the right enclosure. Weight, ventilation and cable routes all matter, and so does keeping the unit somewhere you can get at it.
Your local network operator has to be told. Smaller installations go through a G98 notification after the event; larger ones need G99 approval before work starts, which takes time. Battery storage fitted on its own has carried 0% VAT since February 2024, and that relief is currently set to run until the end of March 2027.
Use an MCS-certified installer. It is the certification that underpins the workmanship standards, and it matters more on a battery than almost anything else we fit — this is a high-voltage electrical installation living inside your house. At DES we use our own directly employed installation teams rather than subcontractors, which means the people on site are the people we train and stand behind. If safety is on your mind, our guide on whether home batteries are safe covers the fire risk question properly.
Battery now, panels later?
This is a sensible route for a lot of households, but tell your installer up front. Whether you go for a hybrid inverter now or AC-couple the battery and add a separate solar inverter later changes what you buy today. Get it wrong and you pay twice. If you are weighing up both, our free suitability checker gives you an honest read on how well your roof would do, and our guide to adding a battery to existing solar covers the reverse case.
Talk to a local installer
If you are thinking about battery storage with or without panels, the useful next step is a proper look at your usage and your tariff rather than a generic quote. We are MCS-certified, based in Wimborne, and we cover Dorset, Hampshire, Wiltshire and the surrounding counties with our own employed teams. Get a free, no-obligation quote and we will tell you straight whether the numbers stack up for your home.