Are solar panels worth it on a UK home?

What decides the output

• Orientation. South facing is best, east and west split the output across the day and still work.
• Pitch. Around thirty to forty degrees suits most UK latitudes.
• Shading. A single chimney, tree or neighbouring roof can cut output disproportionately.
• Available area. Dormers, hips and roof lights fragment the usable space.
• Roof condition. Panels last decades, so a roof due for replacement should be done first.

Self consumption is where the money is

Electricity you use yourself displaces the full price you would have paid to import. Electricity you export earns a lower rate under the Smart Export Guarantee, and rates differ between suppliers. That means a household at home during the day, or one that shifts washing, dishwashing and car charging into daylight hours, gets significantly more value from the same array.

What it does to the EPC

Solar generation is included in the energy model, so panels normally lift the rating. It is often the measure that carries a home the last few points into a higher band, which matters for landlords working to the minimum standard and for buyers looking at green mortgage products.

Practical checks before you commit

1. 1Get at least three quotes with the same array size and panel specification so they are comparable.
2. 2Ask for the estimated annual generation and the assumptions behind it, including shading analysis.
3. 3Check installer certification and what the workmanship warranty covers, not just the panel warranty.
4. 4Confirm the electrical work will be notified to the network operator.
5. 5For a listed building or conservation area, check whether permission is required before you order.

Buying a house that already has panels

Ask whether the panels are owned outright or subject to a roof lease from an older rent a roof arrangement, because a lease can complicate mortgages and sales. Ask for the installation paperwork, any export agreement, the inverter age, and whether the inverter has already been replaced. Inverters have shorter lives than panels.