Solar Energy

Solar energy is a sustainable and renewable source of power derived from the sun's radiant light and heat. It harnesses the immense energy generated by the sun through various technologies, primarily photovoltaic cells and solar thermal systems. Photovoltaic cells convert sunlight directly into electricity, while solar thermal systems use sunlight to heat a fluid. With the potential to provide clean and abundant energy, solar power plays a crucial role in addressing environmental concerns and reducing dependence on fossil fuels. Its versatility, scalability, and decreasing costs have positioned solar energy as a key player in the global transition towards net zero.

In Britain electricity generation by solar energy has increased rapidly over the past 15 years as a result of subsidies and the falling cost of photovoltaic panels. In 2023 over 15.6 GW capacity had been installed with annual generation of 13.9 TWh representing 4.3% of UK electricity consumption. Whilst the UK receives much less solar radiation than the sunniest parts of Europe, the south of the country with a capacity or load factor of around 10% is comparable with central European countries, including Germany, which generates about 7% of its electricity from solar power. Approximately 1/3rd of capacity is on residential rooftop installations with 2/3rds being on large scale solar parks.

Rooftop installations

More than 1.3 million UK homes have solar panel installations representing 4.1% of the 29 million homes in the UK.  The uptake in rural area is highest (for example Powys 11.5%) and lowest in cities. The average size of residential solar PV systems is estimated to be 3.25 kW, Current capacity is approximately 4.5 GW with the potential for this to be significantly increased with the technical potential for residential solar PV in the United Kingdom estimated at 41 GW. The rapid increase in rooftop installations over the past 13 years was largely driven by the Feed in Tariff scheme designed by government to promote the uptake of renewable electricity generation by paying householders for the electricity generated. The scheme was closed to new applicants in March 2019 but grants for solar panels remain available from a number of sources depending on the applicants circumstances. Unlike France and some German states there is currently no requirement in the UK for new buildings to have solar panels.  

Large scale solar parks

Large scale (or commercial) solar farms can range in size from a few acres to hundreds of acres and are typically situated in rural areas where there’s ample land availability. Land usage per MW capacity varies between 2-5 acres per MW depending on the land type and panels used. There are currently around 1,000 solar farms in the UK, the largest of which currently has a capacity of 350 MW and covers an area of over 800 acres, Compared with other forms of renewable energy large scale solar farms are comparatively quick and cheap to construct at around £1 million per MW capacity however as noted above the capacity or load factor is low at around10%. Concerns raised about their impact on landscape, biodiversity and the loss of agricultural land have resulted in the UK government introducing guidelines for solar farms which require developers to carry out environmental impact assessments and to consider the impact on local communities.