ABSTRACT
All the solar energy systems have been active systems. Passive solar energy systems generally have no moving parts and typically are made up of windows and sometimes walls. Windows placed on the south side of a home are passive solar elements. In the winter months, sunshine enters the windows on a sunny day and heats the room. On cloudy days and at night, heat is lost out of the window. Trombe wall is credited to the French engineer, Felix Trombe, who was, in the 1980’s, the director of the French solar facility in the Pyrenees. Trombe wall serves as a heat storage device. When the sun shines, the wall is heated, and at night or during cloudy periods heat that was stored in the wall is transferred to the room. The material used to construct the wall needs to have a relatively high heat capacity given by the product of its density times its specific heat.
