Balcony Solar UK: Kits, Rules & What Fits
Balcony solar — sometimes called plug-in or plug-and-play solar — puts two panels on your railing or balcony floor and offsets your daytime electricity. Here’s what fits a UK flat, the rules for renters, and what an 800W kit actually generates.
What is balcony solar?
A balcony solar kit is a small grid-tied system — usually two 400W panels and an 800W microinverter — designed to hang on a balcony or sit on its floor and plug into a normal socket. It generates while the sun is up and feeds your flat first, cutting what you draw from the grid during the day. It is the same category the UK government calls “plug-in solar”, and the terms are used interchangeably.
What fits a UK balcony
Railing-mounted panels
Clamp brackets hang two 400W panels vertically on a balcony rail. No drilling, fully removable — the most renter-friendly option.
Wall or angled mounts
Adjustable brackets tilt panels toward the sun for more output, ideal on a solid wall or a wide balcony floor.
Free-standing / floor
A weighted A-frame stands on the balcony or a flat roof. Nothing attached to the building at all.
What an 800W balcony kit generates (best day)
| Location | South-facing best day (800W) |
|---|---|
| Cornwall / Devon | 3.0–3.2 kWh |
| London | 2.7–2.9 kWh |
| Bristol | 2.6–2.8 kWh |
| Birmingham | 2.5–2.7 kWh |
| Manchester | 2.3–2.5 kWh |
| Edinburgh | 2.1–2.3 kWh |
| Glasgow | 2.0–2.2 kWh |
Indicative best-day figures for a south-facing 800W kit. East/west ≈ 75–85% of south; north ≈ 40–50%. Enter your postcode in the app for a personalised forecast.
Know your best solar hours
A balcony kit pays back fastest when you run appliances while the sun is out. The free Sun Hours app gives you a personalised 7-day forecast for your exact postcode and balcony aspect — enter two details and Sol tells you when today is a good solar day.
FAQ
Is balcony solar legal in the UK?
From 27 August 2026, a certified kit (up to 800W, batteryless, meeting the Interim Product Specification v2) can legally plug into a standard socket under SI 2026/848. Before then, or for an uncertified kit, a hardwired connection by a qualified electrician with DNO notification is the compliant route.
Can renters install balcony solar?
Usually yes — balcony kits are non-permanent and unplug when you move. Check your tenancy for external-fixing rules and avoid drilling. Leasehold flats and conservation areas may need a quick check if panels are visible from the street.
Does a balcony need to face south?
South is best, but east or west-facing balconies still deliver about 75–85% of south-facing output, and even north-facing gets 40–50%. The Sun Hours app shows your best generation hours for any aspect.
Related: plug-in solar UK guide · certified-kits tracker · the 27 August legalisation, explained