| Expected output (PVGIS) | 1,060 kWh a year per 1 kWp, Exeter, 35 degree pitch, south-facing, 14% losses |
|---|---|
| Distribution licence area | National Grid Electricity Distribution (South West) Plc |
| Grid notice for small systems | Notify National Grid within 28 days of commissioning (G98) |
| Roof panels in England | May project no more than 0.2 m from a pitched roof and sit no higher than the roof's highest part |
What a South West roof can produce
PVGIS is the European Commission’s free solar tool. At Exeter, with a 35 degree pitch, south-facing panels and 14% system losses, it returns about 1,060 kWh a year for each 1 kWp. On the same inputs, central London gets about 1,025 kWh, so the South West sits a little ahead.
The difference is small, however, and your own roof matters more. Pitch, direction and shade all move the result. A quote that promises a big jump over the benchmark deserves a question or two.
Ask each installer for the assumed annual kWh and the inputs behind it, because the inputs decide whether the figure is fair. Our guide on how many panels you need helps you match system size to your use. If your roof faces east and west, the note on east-west against south-facing layouts shows what you give up.
One network operator
Ofgem’s licensee list names National Grid Electricity Distribution (South West) Plc as the distribution licensee for the region, and the ENA guide ties meter numbers starting with 22 to South Western England. National Grid’s connections site lets you check a postcode to see whether it serves your address.
For small systems, National Grid calls its route micro generation (G98). It describes this as a fit and notify process. You must notify it within 28 days of commissioning, and it says the online form takes around 10 to 15 minutes and gives an instant acknowledgement.
Your installer normally files the form. Even so, ask for the acknowledgement, because it proves the notice went in. Our guide to G98 and G99 applications explains when a bigger system needs approval first.
Questions to ask at the survey
Although a sunnier postcode helps, it does not fix a weak design, so use the survey visit well. Ask the surveyor to explain why the panels sit where they do. If part of the roof is left empty, ask whether shade, roof condition or cost drove that choice.
Roof condition matters because panels stay up for many years. Ask whether the quote covers any roof repairs, and who pays if the installer finds a problem once the work starts.
Also ask about the inverter and any battery. Our guide to inverter types explains the trade-offs, and a written answer from the installer will help you compare like with like.
Planning rules for England
England sets its own permitted development rules. Under Part 14 of the England order, panels on a pitched house roof can project no more than 0.2 metres, and they cannot sit above the highest part of the roof. Chimneys do not count towards that height.
The order excludes listed buildings. In a conservation area, panels cannot go on a wall that fronts a highway. If your home may be in a conservation area, check with the council first. Our planning permission guide lists the questions to ask.
For a flat roof on a house, the order allows equipment to rise no more than 0.6 metres above the highest part of the roof. Read our note on solar panels on a flat roof before you agree to a tilted frame, since the 0.6 metre limit applies to the highest part of the equipment.
Exports and funding
The Smart Export Guarantee covers installations located in Great Britain. Licensed suppliers set their own rates and contract lengths, although a rate must always be above zero. Compare several before you choose.
We found no South West scheme on the official pages we checked. Funding therefore follows the national picture, and the grants and VAT guide lists what applies in England. If a salesperson mentions a local grant, ask for the scheme’s official page.
Payback depends on your use, your tariff and the price you pay, because each one changes the result. Our payback guide shows the sums to run on your own numbers. Prices vary, so get written quotes.
How the South West compares with other nations
England’s rules differ from those in Scotland, Wales and Northern Ireland. Scotland’s guidance describes a one metre bubble, where England’s order sets 0.2 metres for a pitched roof. Read the page on how Scottish rules and funding differ if you also own property there.
The neighbouring South East page has different grid steps because two network operators share that region.
Comparing your quotes
Use the quote comparison checklist to line up scope, equipment and warranty terms. Then ask each installer to confirm the grid notice, the scaffolding and the date of any deposit. When you are ready, the free enquiry form can match you with MCS-certified installers.