Do you need a battery with your solar panels?

It comes up at every survey, usually about ten minutes in. Panels, or panels and a battery?

There is no single answer, and anyone who gives you one before asking how your house runs is selling you something.

What a battery actually does

Your panels make most of their power in the middle of the day. Most households use most of theirs between five and ten at night. A battery bridges that gap. It holds what you generate while the house is quiet and gives it back when everyone gets home.

Without one, whatever you do not use at the moment you make it goes back out to the grid.

That matters more than it sounds, and here is the bit worth understanding. Exporting is not the same as using. You get paid for what you export, but you get paid less per unit than you would have spent buying that same unit back off your supplier in the evening. So every unit a battery hangs on to is worth more to you than the same unit sold to the grid.

That gap is the entire case for storage. Everything else is detail.

Who it genuinely suits

Out at work all day. This is the strongest case. Almost none of your generation lines up with when you actually use power, so without storage you are selling most of it cheap and buying it back dear a few hours later.

On a cheap overnight tariff. A battery can fill up at the low rate overnight and run the house through the expensive evening hours. That works even before you put a panel on the roof.

Big evening usage. Electric cooking, a hot tub, a couple of teenagers. If your peak is after dark, storage is doing real work.

Who it suits less

If you are home in the day and using power steadily through daylight hours, you are already using what you make as you make it. A battery then has far less to do. We have told people that on site and talked them out of one, and we would rather do that than fit an expensive cupboard ornament.

Be careful of any sums that only work if your household changes its habits. People do not change their habits.

The VAT point worth knowing

Solar and battery storage fitted at a home are both zero rated for VAT until 31 March 2027. From 1 April 2027 it goes to 5%.

Here is the part most people miss. A battery qualifies on its own. It does not have to go in at the same time as the panels. So you can put the array up this year and add storage next year and still pay no VAT on either, as long as the second job happens before the deadline.

If doing the lot in one go is more than you want to spend right now, that is a genuinely useful thing to know.

Which order to do it in

If money is the constraint, panels first. Panels generate. A battery only moves generation around, so it has nothing to work with until the panels are up.

A battery on its own still earns its keep on the right tariff, so it is not a rule. But for most houses the array is the bigger lever.

If an EV charger is on the list too, say so at the survey. We would rather run the groundwork once than dig up the same route twice, and a charger set to run in the middle of the day turns your roof into fuel.

Working it out for your house

Send us a recent electricity bill and a rough idea of when your house is busy. That is most of the maths done.

We quote solar and battery storage separately so you can see what each one buys you, rather than being handed one number for both and told to trust it. The survey is free, the quote is fixed and in writing, and you are welcome to take it to anyone else.