A solar thermal system guarantees savings for the production of domestic hot water which on average ranges from 50% to 90%. The overall saving reaches 40% in combined systems, i.e. when space heating is integrated, as well as the production of domestic hot water.
The energy requirement for the production of domestic hot water of a gas system plus solar thermal it is about one-fifth that of an electric water heater, less than half that of a gas boiler and about 60% that of a system consisting of a larger electric water heater. solar thermal.
But what is the solar thermal? A solar thermal system mainly produces domestic hot water using the energy of the sun, but is also used to integrate heating systems in the winter season, such as traditional, condensing, heat pump boilers, etc. The main components of a solar thermal system they are: the collector that captures solar energy and converts it into thermal energy, the tank that serves to accumulate the thermal energy produced.
One panel solar thermal (or solar collector) is composed of a radiator capable of absorbing the heat of the sun's rays and transferring it to the water tank. The circulation of water from the tank to the domestic tap is achieved by natural or forced circulation, in the latter case the Solar Panel integrates a hydraulic pump with electric power.
A solar thermal panel it takes about 10 hours to heat the water in the tank; the period of time required is highly variable based on sun exposure, season, weather conditions and latitude. When the sky is overcast and in winter the yield of solar panels drops from 40% to 80%. At night it is only possible to use the hot water previously produced during the day. Once the supply of hot water is exhausted, it will be necessary to wait for the sun and a new heating cycle: for this reason it is always advisable to combine the solar thermal to a gas boiler.