In most domestic situations for roof mounted solar PV no planning consent is needed as it falls under Permitted Development rights. This is not the case for listed buildings or properties forming part of a scheduled monument. For properties in Conservation Areas or part of a World Heritage sites panels should not be installed to the highway frontage.
Planning permission is required for any ground mounted array except for small arrays (9m²) within the curtilage of a domestic property and 5m from a public highway.
Planning consent may be required for solar PV installations to commercial properties.