What a plug-in solar kit costs to own, beyond the kit price.

The costs that sit outside the box, the payback arithmetic using real generation figures for your region, and an honest line wherever a UK price isn't yet known. No number here is guessed.

What one installation costsGreat Britain, as at 13 September 2026

The kit itselfThe government's own figure is £400 to £600 for an 800 W system. It is a European market figure from the impact assessment, it excludes installation, and it is not a UK shelf price.

£400–600*

UK retail priceRead off two British retailers' own pages on 13 September 2026, not taken from anybody's summary. The spread is wide because panel capacity varies. The cheapest works out near 45p a watt, the dearest over £1.

£430–990

Outdoor socket, if neededRequired to be rated IP55 or better where the plug and socket sit outside. Qualified electrician work.

not established

Circuit change, if neededWhere the circuit's overcurrent protection device must be replaced, the specification says only a qualified electrician may do it.

not established

Electrical assessmentAbove 960 W of panel capacity the manufacturer must advise you to have your existing installation assessed.

not established

Mounting hardwareVaries entirely with whether it goes on a wall, in the garden, or on a flat roof.

not established

Planning application, if neededOnly where permitted development does not cover you. DESNZ noted the fees may be high relative to the cost of the device.

not established

Total, all inSix of seven lines are unsourced. Anyone quoting you a confident all-in figure has made most of it up.

not established

We would rather show you an unfinished sheet than a finished-looking guess. Tell us what you paid and we will fill it in properly.

* Source: DESNZ final stage impact assessment. The full wording is that devices "are currently available from around £400 - £600 or less for an 800W system in Europe, excluding any installation or other ancillary costs".

Why we have not filled that sheet in

Because we have not checked, and every site that has filled it in is copying the same handful of numbers around.

In one week we saw UK prices quoted as from £449, typical street prices of £600 to £900, and a claimed sweet spot of £499 to £599. All from sites selling something or earning commission on it. We did not gather any of those figures ourselves, so we do not repeat them, and you should treat them the same way.

The one figure on this site that comes from a document is the government's own. It's European rather than British, and it leaves out installation. We have printed it with both points attached.

What would change this

Real receipts from real UK households. Once we have enough, we will publish a range with the date collected and the number of responses behind it, and you will be able to see how thin or thick the evidence is.

Tell us what you paid

If you've bought a kit, you know something we don't have a source for yet. It takes a minute to tell us.

This is the only way this site gets real UK numbers. We will publish ranges once we have enough of them to be worth publishing, with the date they were collected, and we will say how many they are based on. Nobody's details are published and no seller sees your message.