MCS Certified Solar Thermal Installers UK

Solar thermal panels heat water directly using the sun’s energy, while solar PV panels generate electricity. Solar thermal is specifically designed to provide hot water for your home — a typical system can meet 50–70% of your annual hot water needs. Solar PV is more versatile as the electricity can power anything. Many homeowners install solar PV instead of solar thermal because surplus electricity can be exported to the grid via the Smart Export Guarantee.

A typical solar thermal installation costs £3,000–£5,500 depending on the collector type and whether you need a new hot water cylinder. Evacuated tube collectors are more expensive than flat plate collectors but perform better in the UK’s climate. There is currently no direct government grant specifically for solar thermal, although the Renewable Heat Incentive (RHI) has now closed. The Boiler Upgrade Scheme covers heat pumps and biomass but not solar thermal.

There are two main types: flat plate collectors and evacuated tube collectors. Flat plate collectors are cheaper and more durable but slightly less efficient. Evacuated tubes perform better in overcast conditions and are popular in the UK. Popular brands include Kingspan, Joule, and Thermomax (evacuated tubes). Your installer should recommend the best type based on your roof orientation and hot water demand.

Solar thermal systems need periodic maintenance every 3–5 years. The glycol antifreeze fluid in the system degrades over time and needs replacing. The installer should also check the pump, expansion vessel, and connections. Annual cost for a service is typically £100–£150. Unlike solar PV, solar thermal has moving parts (a pump) and fluid, so maintenance is more important.