The most common application of solar thermal energy is solar water heating.
Solar panels, generally located on a south-facing roof, transform solar radiation into heat. The heat produced during the day is stored in a large hot water cylinder, so that it can be used at any time.
Solar water heating systems are generally sized to cover 50 to 60% of a household’s hot water (about 1 to 1.5 m2 of solar panel per person; 50 litres of water storage per m2 of panel). Such a system will provide almost all of your house’s hot water needs during the summer.
A solar combi-system is based on the same type of components but sized to make a useful contribution (30 to 40%) to total heating requirement of the house (space and water heating). For an average house, this requires between 10 and 20 m2 of solar panels and a storage tank of 800 to 1,500 litres.
The sizing and design of a solar combi-system requires a careful analysis of the heating requirement of the house by an experienced technician.
As it is not feasible to depend on Solar Panels all the time in Ireland, a solar water heater or a solar combi-system needs a back-up heating system like a boiler (gas, oil or pellets), a heat pump or an electric heater.