Solar Panels in Cefn Fforest, Caerphilly

A 4kWp system in Cefn Fforest 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 Cefn Fforest's solar yield of 831 kWh/kWp, a 4kWp system generates approximately 3,324 kWh/year, paying for itself in 11-13 years through electricity savings of £592+/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.

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.

Solar PV panels generate electricity from sunlight using photovoltaic cells, while solar thermal panels heat water directly using the sun's warmth. For most UK homes, solar PV is the better investment: it is more versatile (powering all electrical appliances), benefits from 0% VAT, and you can sell excess electricity via the Smart Export Guarantee at around 13-15p/kWh. Solar thermal only heats water and does not generate electricity or qualify for SEG income. Solar PV panels also last longer (25-30 years versus 15-20 for solar thermal) and have lower maintenance requirements.

Shading from trees, chimneys, or nearby buildings can reduce output significantly, even partial shading on one panel can affect the whole string in older systems. Modern systems use power optimisers or microinverters so that shading on one panel does not drag down the performance of other panels, typically recovering 20-25% of otherwise lost generation. Your MCS-certified installer will assess shading patterns throughout the year during the site survey using specialist tools. If shading is unavoidable, optimisers add approximately £50-£80 per panel but are well worth the investment for maintaining overall system performance.

Most roofs are suitable for solar panels. You need at least 18-20 m² of unshaded roof space for a typical 4kWp system (10 panels at ~400W each). South-facing roofs at 30-40° produce the best yield, but east and west-facing roofs still achieve 80-85% of optimal output. Your MCS-certified installer will assess your roof's orientation, pitch angle, shading from trees or buildings, and structural suitability during a site survey. Slate, tile, and metal roofs are all suitable, though flat roofs require angled mounting frames which add slightly to the cost.

Yes. East or west-facing roofs still produce 80-85% of the output of a south-facing roof, making them well worth installing. Many installers recommend splitting panels across east and west faces to spread generation throughout the day, which can improve self-consumption and reduce the amount of electricity exported at the lower SEG rate. East-facing panels generate more in the morning, while west-facing panels peak in the afternoon, both align well with typical household usage patterns. Only north-facing roofs are generally unsuitable for solar in the UK.

In most cases, regular UK rainfall keeps solar panels clean enough to perform well. If your panels are near trees, under bird flight paths, or at a low pitch angle (below 15°), an annual clean may improve output by 2-5%. Never use abrasive materials, pressure washers, or household cleaning products, a soft brush and clean water is sufficient. Professional panel cleaning services typically cost £50-£100 per visit. Your panels have no moving parts and require very little maintenance over their 25-30 year lifespan.