Description
A passive solar building is one in which the flow of heat from solar energy is achieved by natural means. Thermal conduction, free convection, and radiation are used to transport heat rather than the pumps and blowers associated with active solar heating systems.. In most cases, the elements of a passive solar system are integral parts of the building for which heat is provided. A direct gain building, for example, admits sunlight through ordinary south-facing windows that have good exposure to the low winter sun. The sunlight bounces around the interior until most of it is absorbed on the bounding surfaces. The absorbed solar energy is transformed into heat; part of it serves to meet the current heat load of the building whereas the remainder is stored in the structural mass for later use after the sun has set.