päikeseküte

Päikeseküte on term for solar thermal heating systems that convert sunlight into heat for residential or commercial buildings. It generally refers to solar thermal technology that heats water or air rather than generating electricity.

There are two main types: passive solar heating (design choices that collect and store solar heat through building mass and orientation) and active solar heating (systems that use collectors, pumps, and storage). Active systems use flat-plate or evacuated-tube solar collectors, which capture solar radiation and transfer heat to a working fluid (usually water or heat-transfer oil). The heated fluid passes to a storage tank or heat exchanger, from which the heat is distributed for domestic hot water or space heating. In colder months, an auxiliary heater such as a gas boiler or heat pump is used as backup.

Performance depends on collector efficiency, storage, heat losses, and climate; in northern latitudes like Estonia or the Baltic region, seasonal storage and well-insulated tanks are important. Proper installation, antifreeze in closed-loop systems, and controls to prevent overheating and freezing are standard concerns.

Advantages include reduced fossil fuel consumption, stable energy costs, and low operating emissions; payback periods vary based on price, incentives, and building energy demand. Limitations include weather dependence, higher upfront costs, space requirements for collectors and storage, and potential overheating risk in summer without proper controls.

Päikeseküte is distinct from solar photovoltaic systems, which generate electricity rather than thermal energy. It is part of broader sustainable building practices and is supported by national and EU energy efficiency policies in many European countries.