Key takeaways
- • Plug-in solar in Great Britain is limited to a maximum output of 800W.
- • Savings depend heavily on how much electricity you use during daylight hours.
- • Permission may be required if you rent, lease or live in a managed building.
Balconies are the classic plug-in solar location, and also the one with the most rules attached.
Assess the balcony first
Note the direction it faces, how many hours of unshaded sun it gets between 10am and 4pm, the railing type and whether you are above the second floor. South and west facing balconies perform best; north facing is rarely worth the money.
Mounting choices
Railing clamps are quickest and avoid drilling. Vertical mounting loses roughly a quarter to a third of annual output compared with a 35 degree tilt, but tilt brackets that overhang the rail may not be permitted. Balustrade-mounted panels must be secured against wind uplift with fixings rated for the job.
Permission
Balcony structures are usually retained by the freeholder even in an owned flat. Get written consent, and expect questions about appearance and safety from a managing agent.
Electrical connection
Have an electrician fit a dedicated connection point on a circuit that can accept the generation. Trailing cables through a door or window are a trip and weather risk and will invite objections.
Realistic expectations
A vertical 800W balcony system in the Midlands typically produces 380-500 kWh a year, saving roughly £70-£110 depending on how much you consume live.
Frequently asked questions
Sources
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