Planning Permission for Solar & Heat Pumps in Cornwall: Full Guide 2026
Most solar panel and heat pump installations in Cornwall fall under permitted development rights — meaning no planning permission is needed. But there are important exceptions: conservation areas, listed buildings, and AONBs all have additional restrictions. This guide explains exactly when permission is and isn't required.
Permitted Development Rights: The Basics
Most solar panel and heat pump installations on residential properties in Cornwall fall under permitted development rights — meaning no planning permission is needed, provided the installation meets specific criteria. However, these rights can be restricted or removed in specific circumstances: conservation areas, listed buildings, and large installation sizes.
Solar Panels: Permitted Development Criteria
- Panels do not protrude more than 200mm above the roof plane
- Panels are not installed on a wall or roof slope facing a highway
- The property is not a listed building (requires listed building consent)
For standalone ground-mounted solar, permitted development allows systems up to 9m² within the curtilage of a dwelling. Larger arrays need full planning permission.
Heat Pumps: Permitted Development Criteria
- Volume of the outdoor unit does not exceed 0.6m³
- Unit is not installed on a roof (wall or ground mounting only)
- Only one heat pump installed at the property
- Unit is at least 1 metre from the property boundary
- Not on a listed building or within a conservation area on a highway-facing wall
- Meets MCS planning standards for noise (typically 42dB at 1 metre)
Conservation Areas in Cornwall
Cornwall has over 140 conservation areas. Key areas in our service territory:
- Fowey: Extensive conservation area. Solar panels on highway-facing roofs require permission.
- Lostwithiel: Medieval town centre. Front elevation restrictions apply.
- Mevagissey: Working fishing village. Heat pumps on harbour-facing walls require permission.
- Charlestown: UNESCO World Heritage Site buffer zone. Pre-application advice strongly recommended.
- Truro city centre: Multiple conservation areas around the cathedral and historic streets.
See also: Solar Panels in Cornwall Conservation Areas.
Listed Buildings
Listed buildings require listed building consent for alterations that affect the character of the building — including solar panels and heat pump outdoor units. This is separate from planning permission and must be applied for even if the installation would otherwise be permitted development.
AONBs & National Landscape Designations
The Cornwall AONB covers parts of the Roseland Peninsula, coast between Mevagissey and Fowey, and areas around Bodmin Moor. Permitted development rights for domestic solar and heat pumps are the same within AONBs as outside — designation does not remove PD rights for domestic installations. However, AONB designation is a material consideration if a full planning application is required for other reasons.
Pre-Application Advice
If uncertain, Cornwall Council's Planning Department offers a pre-application advice service for £66 (2026 fees), with a written response within 20 working days. CCS Heating & Renewables will advise you during your free survey whether your installation requires any planning application. Book a free survey and we'll assess your specific property's planning position as part of the visit.
Need personalised advice?
Our MCS certified engineers can answer your questions and provide a free, no-obligation assessment for your property.