Solar Panels in Llanfoist, Monmouthshire

A 4kWp system in Llanfoist typically costs £6,600-£8,500 with 0% VAT included, the zero-rate VAT alone saves around £1,300-£1,700 compared to the standard 20% rate. Based on Llanfoist's solar yield of 825 kWh/kWp, a 4kWp system generates approximately 3,300 kWh/year, paying for itself in 11-13 years through electricity savings of £587+/yr and Smart Export Guarantee income of around 13-15p/kWh. Adding a home battery (5-10 kWh) costs an additional £3,000-£6,500 and also benefits from 0% VAT. We recommend getting at least three quotes from MCS-certified installers to compare pricing and equipment.

A smart meter is required to sell surplus electricity back to the grid under the Smart Export Guarantee (SEG) and earn around 13-15p/kWh for your exports. Your energy supplier will install a smart meter for free if you do not already have one, contact them before or shortly after your solar installation. You do not strictly need a smart meter for the solar panels themselves to work, but without one you cannot receive SEG payments. Your MCS-certified installer submits the G98/G99 application to your Distribution Network Operator after installation to register your system for grid export.

Most homes in Llanfoist benefit from a 3-6 kWp system. A 4kWp system (10 panels at ~400W each) generates 3,300 kWh/yr at Llanfoist's yield of 825 kWh/kWp, covering 87% of average household electricity use. The system requires approximately 18-20 m² of unshaded roof space. If you have an electric vehicle or heat pump, a larger 5-6 kWp system (12-15 panels) may be more appropriate to offset the additional demand. Your MCS-certified installer will assess your roof space, orientation, shading, and electricity consumption to recommend the optimal size during a site survey.

The Smart Export Guarantee (SEG) is a UK government scheme that requires licensed energy suppliers with 150,000+ customers to offer a tariff to small-scale generators for surplus electricity exported to the grid. Typical rates are around 13-15p/kWh, with some suppliers offering up to 30p/kWh on time-of-use or agile tariffs (such as Octopus Flux with a battery) that pay more during peak demand. You need a smart meter and an MCS-certified installation to be eligible. Your energy supplier will install a smart meter for free if you do not already have one. The SEG replaced the Feed-in Tariff scheme, which closed to new applicants in 2019.

Standard grid-tied solar systems shut down automatically during a power cut for safety reasons, this is to protect engineers working on the grid lines. Your panels will resume generating as soon as the grid power is restored. If you need backup power during outages, you can install a hybrid inverter with battery storage that isolates your home from the grid and continues supplying electricity from the battery and panels. This emergency power supply (EPS) feature is available on most modern hybrid inverters and is worth considering if you experience frequent power interruptions.

Based on PVGIS satellite data for Llanfoist's coordinates, a 4kWp system generates approximately 3,300 kWh per year at a yield of 825 kWh/kWp, covering 87% of average household use (3,800 kWh/year). The area receives around 1,460 sunshine hours annually. Monmouthshire ranks #46 of 102 UK counties for solar yield, above the national average. Output peaks between May and August and is lower in winter, though annual generation figures already account for this seasonal variation. South-facing roofs at a 30-40° pitch achieve optimal yields, while east or west-facing roofs still produce 80-85% of maximum output.

Yes. Under the UK's Smart Export Guarantee (SEG), licensed suppliers with 150,000+ customers must offer a tariff for surplus electricity you export to the grid. Typical rates are around 13-15p/kWh, with some suppliers offering up to 30p/kWh on time-of-use tariffs like Octopus Flux when paired with a battery. You need a smart meter and an MCS-certified installation to be eligible, your supplier will install a smart meter for free if needed. A typical 4kWp system without battery storage exports around 50-60% of its generation, providing a meaningful income stream alongside electricity bill savings.