Lämpökeräins

Lämpökeräin, often translated as heat collector or thermal collector, is a device designed to absorb solar radiation and convert it into thermal energy. This captured heat is then typically used for heating water or air, or for other applications requiring low-grade heat. The fundamental principle behind a lämpökeräin is that sunlight, which carries energy, strikes a dark surface. This surface absorbs the solar energy and heats up. This heat is then transferred to a fluid, such as water or a mixture of water and antifreeze, that circulates through the collector.

There are several common types of lämpökeräins. Flat-plate collectors are the most prevalent, consisting of an insulated box with a transparent cover (usually glass) over a dark absorber plate. Fluid-carrying pipes are attached to or form part of the absorber plate. Evacuated tube collectors are another type, utilizing a series of glass tubes that are vacuum-sealed. Each tube contains an absorber element and a heat pipe. The vacuum between the glass layers acts as an excellent insulator, reducing heat loss and making evacuated tube collectors more efficient, especially in colder climates.

The heat collected by a lämpökeräin can be stored in a hot water tank for later use. This stored heat can then be distributed for space heating or domestic hot water. Lämpökeräins play a significant role in renewable energy systems, contributing to reduced reliance on fossil fuels for heating purposes. Their efficiency and effectiveness are influenced by factors such as collector design, installation angle, climate, and maintenance.