Solar space heating is one of the more intuitive use of solar thermal energy by using the sun’s heat to subsequently heat spaces within buildings. The technologies within space heating can be separated into two distinct categories: passive and active.

Passive Space Heating

Passive solar space heating involves the design of buildings to absorb, store, and redistribute thermal energy without the use of mechanical equipment. This effect can be achieved through the use of specific materials, architectural features, and an understanding of thermal fluids. A common passive feature is a Trombe wall, which uses a glass wall and a masonry wall to trap thermal energy in a gap between walls. This trapped energy can then be used to flow through the rest of the building and stimulate air circulation for hours afterwards.

Trombe Wall (Meadow Lark Builders)

Active

Active space heating, while built on many of the same principles as passive, differs vastly in its versatility and complexity. Collectors are required in active heating to absorb the thermal energy and redistribute the heated fluid. These collectors differ from passive systems in their ability to include energy storage and their more standardized design. Placing large flat-plate or evacuated tube collectors on a roof is functionally similar to implementing photovoltaic electricity cells. These collectors differ in their temperature efficiency ranges, but their ultimate purpose remains the same. Industrial process heating is a larger consumer of active solar thermal technologies than passive design, due to its high upfront costs and higher efficiencies.

Authored by: Sam Brinton

Edited by: Chris Castello