Solar Panels UK: Frequently Asked Questions
Answers to common questions about weather, planning permission, maintenance, and lifespan.
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Do solar panels work on cloudy days?
Yes, absolutely. Solar photovoltaic (PV) panels run on light, not heat. While they generate less power than on a sunny day (typically 10-25% of peak output), they still work effectively in the UK's overcast climate.
Do I need planning permission?
In most cases, no. Solar panels are considered 'Permitted Development' in England, Scotland, and Wales. Exceptions include listed buildings and homes in conservation areas (though even these are often approved if panels are not street-facing).
How many panels do I need?
A typical 3-bedroom semi-detached home usually installs a 4kW system, consisting of about 10-12 panels. This occupies roughly 20-25 square metres of roof space.
What happens when the panels get dirty?
In the UK, rainfall is usually substantial enough to wash away dust and debris. However, if you live near a busy road or beach (salt spray), a professional clean every 2-3 years can maintain 100% efficiency.
Do solar panels increase property value?
Yes. Research suggests homes with higher Energy Performance Certificate (EPC) ratings sell faster and for more money. Solar panels typically improve a home's EPC rating by at least one band.
How long do they last?
Most modern panels come with a 25-year performance warranty (guaranteeing 80-85% output). The system will likely keep generating for 30-40 years. The inverter typically needs replacing after 10-12 years.