Solar Panels in St Fagans, Cardiff

A 4kWp system in St Fagans 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 St Fagans's solar yield of 885 kWh/kWp, a 4kWp system generates approximately 3,540 kWh/year, paying for itself in 11-13 years through electricity savings of £630+/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.

Modern solar panels are warrantied for 25-30 years and typically last even longer with minimal maintenance. Panel efficiency degrades by just 0.3-0.5% per year, so after 25 years, your panels will still produce around 85-90% of their original output. Inverters typically last 10-15 years and may need one replacement over the system's lifetime, costing around £900. With a typical payback period of 11-13 years, that leaves 12-19 years of near-free electricity generation. Panels require very little upkeep, UK rainfall keeps them clean in most cases.

Solar panels need very little maintenance over their 25-30 year lifespan. UK rainfall keeps them clean in most cases, and there are no moving parts to wear out. Your inverter may need replacing once during the system's lifetime (10-15 year lifespan, costing around £900). An annual visual check to ensure no debris, bird nesting, or damage is recommended, along with occasional cleaning if panels are near trees or at a low pitch angle. Some installers offer maintenance packages, but these are generally optional rather than essential.

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 residential solar installations in the UK are classed as permitted development and do not require planning permission, provided panels do not project more than 200mm from the roof surface. Listed buildings, conservation areas, Areas of Outstanding Natural Beauty (AONBs), and World Heritage Sites may have additional requirements from your local planning authority. Ground-mounted systems are also permitted development if they do not exceed 9m² in area. Your MCS-certified installer can advise on any local restrictions that apply to your property.

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.

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.