What percentage of my hot water will come purely from the solar system in the UK?
The UK receives slightly more than half of the solar energy received at the equator, definitely enough to operate a solar water heating system. As you can see above, this varies depending on where you are in the country, with best returns in the south . A typical solar water heating system in the UK provides 50% – 60% of annual domestic hot water requirements. This is spread out over the year to approximately 90% in summer, 50% in spring, and 20% in winter. A solar system provides heat input even on cloudy days by utilising energy from diffuse light. In winter the system will pre-heat the water in the cylinder, meaning the solar system will make meaningful reductions to the gas, oil or electricity consumption throughout the year. The solar water heating system works alongside the existing hot water system. On cloudy days, the little sunlight there is will preheat the water in the cylinder – and the boiler or immersion heater will do the rest.
