The short answer for Devon: a 4kW south-facing system in Devon generates about 4,210 kWh a year on the EU's PVGIS model — about 3% more than London. Installed prices for that size run roughly £6,600–£7,800 on the UK government's 2025/26 cost data, and at October–December 2026 South West electricity prices (26.58p/kWh) it is worth roughly £800 a year without a battery, or £900 if a battery lets you use most of it yourself.
Devon is big enough for the sun to vary across it. On the same PVGIS settings a south-facing kW makes about 1,120 kWh a year at Plymouth, 1,050 at Exeter and 1,020 at Barnstaple. Add two National Parks, five National Landscapes, many detached rural homes and more than one home in five heated by oil, LPG or electricity alone, and a good Devon quote depends a lot on where you live.
How much a solar panel system generates in Devon
The table uses the European Commission's PVGIS tool for Exeter: crystalline panels at a 35° pitch, with PVGIS's standard 14% allowance for system losses and the local horizon. Your installer's MCS estimate will differ a little because MCS uses its own irradiance tables and your actual pitch and shading, but the gap between places and orientations is what matters here.
| Roof faces | Per kW | 3kW system | 4kW system | 6kW system |
|---|---|---|---|---|
| South | 1,052 kWh | 3,160 kWh | 4,210 kWh | 6,310 kWh |
| East | 837 kWh | 2,510 kWh | 3,350 kWh | 5,020 kWh |
| West | 836 kWh | 2,510 kWh | 3,340 kWh | 5,020 kWh |
Annual output, PVGIS 5.3 (SARAH3 satellite data, 2005–2023) for Exeter, fetched 30 October 2026. Actual output varies year to year.
Of the 25 areas we cover, Devon ranks fifth for south-facing yield (Dorset is highest at 1,126 kWh per kW, Glasgow lowest at 853). The seasons matter as much as the location: in December a 4kW system here makes about 141 kWh for the whole month, against 500 kWh in June — which is why a battery is mostly a summer and shoulder-season tool, and why nobody should promise you winter bills near zero.
The table uses Exeter as the middle of the county. South Devon and the coast around Plymouth model about 7% higher; north Devon around Barnstaple about 3% lower. East- and west-facing roofs make roughly four-fifths of a south-facing one throughout. On Dartmoor and Exmoor, and in the deep river valleys, the hills around you matter more than the county figure, so trust the surveyor's shading check for your own roof.
Coastal homes: on both coasts, ask for panels certified for salt-mist corrosion (IEC 61701), stainless or coated fixings, and a warranty that doesn't exclude coastal exposure. Exposed north coast and moorland roofs also take more wind, so ask how the fixings are rated.
What solar costs and saves in Devon
There is no separate "Devon price" for solar — installers price by system size, roof and access — so the fairest benchmark is the government's own cost series. Across domestic installations registered with MCS between April 2025 and March 2026, the average installed cost was £1,955 per kW for systems up to 4kW and £1,645 per kW for 4–10kW, VAT included and batteries excluded.
| System | Output in Devon | Typical installed price | Year-one value, no battery | Simple payback |
|---|---|---|---|---|
| 3kW | 3,160 kWh | £4,900–£5,900 | £600 | 9–10 years |
| 4kW | 4,210 kWh | £6,600–£7,800 | £800 | 9–10 years |
| 6kW | 6,310 kWh | £9,900–£11,700 | £1,100 | 9–10 years |
Price range: DESNZ Solar PV cost data (published 28 May 2026), each size priced between the 4–10kW average (£1,645/kW) and the up-to-4kW average (£1,955/kW); bigger systems tend towards the lower figure per kW. Value: south-facing PVGIS output, 40% used in the home at the South West price-cap unit rate of 26.58p/kWh (1 October to 31 December 2026), the rest exported at 12p/kWh (the 12p rate several large suppliers pay their own import customers in September 2026). Payback ignores panel degradation, future price changes and inverter replacement.
Two things move those numbers more than anything about Devon itself. First, how much you use yourself: every unit you use saves 26.58p, every unit you export earns only what your export tariff pays — 12p in this illustration. Our illustration assumes you use 40% without a battery; with a battery taking that to around 70%, the same 4kW system is worth about £900 a year — but the battery adds several thousand pounds, so price it as its own line and judge it on its own payback (battery storage guide). Second, the export tariff: rates are set by suppliers, not Ofgem, and range widely — see the solar payback guide for current examples.
VAT on solar panels and batteries installed in homes is 0% until 31 March 2027 (how the relief works), so a quote that adds 20% VAT to a domestic install is wrong.
Devon homes and what they mean for your roof
Census 2021 counted 352,620 households in Devon: 26.2% semi-detached, 22.7% terraced, 35.8% detached and 14.4% flats or maisonettes, with 68.2% owner-occupied and 19.0% privately rented (England and Wales: 61.6% owned).
These census figures are for the Devon County Council area, which doesn't include Plymouth or Torbay. With so many detached, owner-occupied homes, many roofs can take a 5–6kW system if your use justifies it. Plymouth and Torbay are different: a quarter of Plymouth households and three in ten in Torbay live in flats, where the freeholder or management company has to agree before panels go on a shared roof.
Older Devon houses bring their own questions. Panels are not fixed to thatch, so a thatched cottage needs an outbuilding roof or a ground-mounted array. Natural slate is common and slower to work on than concrete tile; ask how the brackets will be fixed and who pays for any broken slates.
Devon's heating is unusual: 10.1% of households heat with oil alone, 2.3% with LPG alone and 10% with electricity alone (Census 2021). For all-electric homes, solar cuts the most expensive daytime units directly. If you heat with oil, plan solar with a future heat pump in mind: see heat pump grants for oil and LPG homes.
Planning permission in Devon
For houses in England, roof-mounted solar is permitted development — no planning application — as long as the panels stand no more than 20cm proud of the roof slope and don't rise above the highest part of the roof. The main exceptions are listed buildings (which need listed building consent), panels mounted on a wall that faces a road in a conservation area, and properties where the council has removed permitted development rights with an Article 4 direction. Blocks of flats have their own, similar permitted development rules, but panels on a shared roof still need the freeholder's consent. The rules were last amended on 27 August 2026.
Devon County Council doesn't decide house planning: that is done by the city or district council (Exeter, East Devon, Mid Devon, North Devon, South Hams, Teignbridge, Torridge or West Devon), or by Plymouth or Torbay council (Devon County Council; council structure). Inside Dartmoor National Park, and the third of Exmoor National Park that lies in Devon, the Park Authority is the planning authority (Devon County Council).
Devon has five National Landscapes: the Blackdown Hills, East Devon, North Devon, South Devon and the Tamar Valley. With the two National Parks, these protected landscapes cover 35% of the county (Devon County Council). Roof panels on a pitched roof stay permitted development in all of them. Dartmoor National Park Authority says panels on a house usually don't need permission, with the main exceptions being listed buildings and flat roofs (Dartmoor FAQ). On a flat roof in either National Park, a National Landscape, a conservation area or a World Heritage Site, you must apply to the planning authority before work starts, so it can decide whether it needs to approve how the panels will look (GPDO Part 14, A.2(ba)). Exmoor National Park Authority says roof panels on a house generally don't need permission, and that its Local Plan supports freestanding arrays, though a ground-mounted array is likely to need permission (Exmoor guidance).
Devon has parts of two World Heritage Sites: the Jurassic Coast east of Exmouth, and the Cornwall and West Devon Mining Landscape (Devon County Council). The Jurassic Coast boundary follows the cliff tops and the back of the beach and leaves out the Sidmouth and Seaton frontages (site boundary statement), so few homes are in it. Inside either site, as in a conservation area, panels can't go on a wall, balcony or roof enclosure facing a road. A listed house always needs consent.
Connecting to the grid: National Grid Electricity Distribution (South West)
All of Devon, including Plymouth and Torbay, is on National Grid Electricity Distribution's South West network and in the South West price-cap region used in the tables above (Ofgem). Your installer notifies or applies to it for the connection; your electricity supplier is a separate company. Many rural Devon homes sit at the end of long lines, where a larger system, or panels with a big battery, is more likely to need G99 approval or an export limit, so ask early whether your design needs one.
For a typical home system the installer handles this. A single-phase installation up to 3.68kW of inverter capacity (16 amps per phase) is connected under the G98 process and the network operator is notified within 28 days of commissioning. Anything larger — including a bigger system, or panels plus a battery whose combined inverter capacity passes that limit — goes through G99, which needs the network operator's approval before installation and can add weeks. Ask your installer which route your design needs and whether an export limit is being applied.
Getting a quote in Devon
Tell us about your home
Postcode, property type and how you'd pay. Two minutes.
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If an accredited (MCS-certified) installer covers your area, we'll pass your enquiry to them, and only them. They can arrange a roof survey and quote.
Judge the quote
Check it against the figures on this page. If it's out of range, you can say no. No obligation at any stage.
How your enquiry is handled
- One installer introduction, fulfilling your request. If an accredited (MCS-certified) installer covers your area, we'll pass your enquiry to them, and only them — not a list of companies.
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- It costs you nothing. An installer may pay Great British Energy a referral fee if you go ahead, and that fee does not change your price.
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Get your solar quote in Devon
One MCS-certified installer who covers your postcode. Nothing is shared until you submit.
What the quote should show
- The installer's MCS certificate number — needed for a Smart Export Guarantee tariff — and their consumer code (RECC or HIES).
- Named panel and inverter make and model, with quantities, and the MCS performance estimate for your roof in kWh a year. Every saving quoted to you should come from that estimate.
- Scaffolding stated as included or excluded, and any battery priced as a separate line.
- No VAT added on a home installation (0% until 31 March 2027), warranty terms split out, and, if financed, the total repayable next to the cash price.
The full checklist is on the solar quotes page.
Questions from Devon homeowners
Is Devon good for solar panels?
Yes. On PVGIS data a south-facing roof at Exeter makes about 3% more per kW a year than the same roof in London, and the south coast around Plymouth about 10% more. North Devon around Barnstaple is about the same as London. Your savings depend mostly on how much of the output you use yourself.
Do I need planning permission for solar panels on Dartmoor?
Not usually for panels on a pitched roof of a house. For panels on a flat roof you must apply to Dartmoor National Park Authority before installation, so it can decide whether it needs to approve their appearance, and a listed building needs consent. Ask the Authority if you are unsure.
Can I put solar panels on a thatched or cob house in Devon?
Not on the thatch itself; the usual options are an outbuilding roof or a small ground-mounted array. Cob or stone walls do not change the planning rules; what matters is the roof covering and its condition. If the house is listed, you need consent first.
Do solar panels cope with sea air in Devon?
Good ones do. Near either coast, ask for panels tested to the salt-mist standard IEC 61701, corrosion-resistant fixings, and a warranty that doesn't exclude coastal sites.
Who connects solar panels to the grid in Devon?
National Grid Electricity Distribution, which runs the South West network across all of Devon, including Plymouth and Torbay. Your MCS installer notifies it, or applies for approval first for a bigger system.
Other areas
- Solar in Birmingham
- Solar in Newcastle
- Solar in Manchester
- Solar in Bristol
- Solar in Sheffield
- Solar in Doncaster
- Solar in Nottingham
- Solar in Cornwall
- Solar in Aberdeen
- Solar in Cambridge
- Solar in Cardiff
- Solar in Derby
- Solar in Dorset
- Solar in Edinburgh
- Solar in Essex
- Solar in Glasgow
- Solar in Hull
- Solar in Kent
- Solar in Leeds
- Solar in Leicester
- Solar in Liverpool
- Solar in London
- Solar in Norfolk
- Solar in Telford & Shropshire
Heat pump pages: Birmingham, Bristol, Newcastle, Nottingham, Sheffield, Doncaster, Norfolk, Suffolk, West Wales, and all heat pump quotes.
Solar for a shop, office, farm or factory instead? See commercial solar panels and the business energy audit guide.
Sources
- European Commission JRC, PVGIS 5.3 — grid-connected PV, Exeter, 1kWp crystalline silicon, 35° slope, 14% system loss, south/east/west, SARAH3 2005–2023; queried 30 October 2026.
- Office for National Statistics, Census 2021 tables TS044 (accommodation type), TS046 (central heating), TS050 (bedrooms) and TS054 (tenure), local authority level, via Nomis.
- DESNZ, Solar PV cost data, updated 28 May 2026 — domestic, mean cost per kW, Total Installed Capacity basis, 2025/26 (Official Statistics in development).
- Ofgem, Changes to energy price cap between 1 October and 31 December 2026 (26 August 2026) and regional unit rates and standing charges; electricity at 0% VAT from 1 October 2026 to 31 March 2027 (HMRC).
- Ofgem, Smart Export Guarantee: tariffs must be above zero; suppliers with 150,000+ domestic customers must offer one. Supplier export rates checked on supplier websites, 23 September 2026.
- HMRC, VAT Notice 708/6: 0% on installing energy-saving materials in homes, 1 May 2023 to 31 March 2027.
- Town and Country Planning (General Permitted Development) (England) Order 2015, Schedule 2 Part 14 Class A, as amended to 27 August 2026.
- Network connection thresholds (G98 up to 16A per phase — 3.68kW single-phase; larger systems G99): SP Electricity North West; find your operator via the Energy Networks Association.
- Devon County Council, national and UNESCO designations, planning and how local government in Devon is structured; Dorset and East Devon Coast World Heritage Site: statement on the boundaries (checked 30 October 2026).
- Dartmoor National Park Authority, do I need planning permission for solar panels?; Exmoor National Park Authority, guidance for domestic solar PV (checked 30 October 2026).
- Town and Country Planning (General Permitted Development) (England) Order 2015, Schedule 2 Part 14 (as amended to 27 August 2026); Ofgem, price cap rates by region; network area checked by postcode on the industry grid supply point lookup (30 October 2026).