They have long been a feature of rooftops in southern European countries, but with dramatic advances in solar technology, they can now be seen anywhere from Sweden to Cyprus. There are as many solar collectors per capita in Austria as in Greece, even if this technology relies upon solar radiation that is not equally available throughout the year. Despite the fact that solar heating systems include their own heat storage, a low-carbon backup solution is required to supplement this fully carbon-neutral technology to achieve full coverage of heat demands. The natural partner technology for solar thermal power in rural areas is gas (natural or LPG). A gas-condensing boiler can harness all the benefits of solar-heated water, whilst providing a constant source of low-carbon-generated heat whenever it is needed throughout the year.
Solar energy utilises roof-mounted sun collectors that supplement conventional boilers.
It provides hot water and space heating.
Solar energy is used mainly in residential and sometimes commercial buildings.