Photovoltaics (PV)
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Also known as: PV, solar PV, solar panels, photovoltaic
Definition
Photovoltaics (PV) is the technology that converts daylight directly into electricity using solar cells, usually fitted together as panels. A domestic solar PV system also needs an inverter to convert the direct current the panels produce into the alternating current used in the home.
In practice
System size is quoted in kilowatts peak (kWp), the output under standard test conditions. A typical three-bedroom home system is around 4kWp, roughly nine or ten panels. Output depends on orientation, pitch, shading and location. Electricity you use yourself saves the full import price, while surplus can be exported and paid for through the Smart Export Guarantee.
Installations up to 50kW normally need an MCS-certified installer to join a Smart Export Guarantee tariff, and the network operator must be told about the connection under G98 or G99. In England, roof-mounted panels on houses are generally permitted development, subject to conditions.
Building Regulations
Rules were amended for domestic solar in England from 27 August 2026. Check the Planning Portal and your council for the current conditions.
Full guide: Solar PV for UK homesSee also