The short answer: an 800 W plug-in solar kit costs around £400 to £600, with no installation cost. The government says a kit can save a household up to £110 a year.
What a kit costs
| Item | Typical cost |
|---|---|
| 800 W kit: panels, micro-inverter and plug | Around £400 to £600 |
| Installation | None. You fit it yourself |
| Mounting kit for a balcony, wall or ground frame | Sometimes included, sometimes extra |
The price range comes from the government's own impact assessment. Check that any kit you buy complies with the UK product specification for plug-in solar.
What it saves
The government's figure is a saving of up to £110 a year. What you actually save depends on:
- How much of the power you use. Plug-in solar only saves money on electricity you use while the sun is shining. If the house is empty all day, much of the output is wasted.
- Where the panels sit. A south-facing, unshaded spot produces far more than a shaded balcony.
- Your electricity price. Savings rise and fall with the price cap.
Payback
| Kit price | Yearly saving | Payback |
|---|---|---|
| £400 | £110 | About 4 years |
| £600 | £110 | About 5.5 years |
| £600 | £60 | 10 years |
These are our own calculations. The last row shows a household that uses only about half of what the kit produces.
Costs people forget
- No export payments. Plug-in kits are not certified installations, so they do not qualify for the Smart Export Guarantee.
- Mounting. A secure, weatherproof fixing matters, especially on a balcony.
- Permissions. Renters and flat owners may need consent, which can take time. See plug-in solar for renters and flats.
Plug-in or rooftop?
For each pound spent, plug-in solar is cheaper to buy per watt than a rooftop system. But a rooftop system is five times the size, earns export payments and can add value to the home. See plug-in solar or rooftop solar.
Back to plug-in solar panels.
Sources
Correct at the time of publication, 14 November 2026.
- GOV.UK, "Households can save as plug-in solar panels come to market", 26 August 2026: https://www.gov.uk/government/news/households-can-save-as-plug-in-solar-panels-come-to-market
- Department for Energy Security and Net Zero, plug-in solar final stage impact assessment: https://assets.publishing.service.gov.uk/media/6a58f6be5ca06bf11ccb435d/plug-in-solar-final-stage-impact-assessment.pdf
- Payback figures are our own calculations.