An air cavity is left between the collector and the building wall. A fan inside the building draws air through the holes in the collector, up through the space between the collector and the building, and delivers the fresh air to the building. Ventilation air is heated by solar energy Instead of using conventional heating fuels to heat ventilation air, the Solarwall system uses the renewable resource of solar energy. Building heat normally lost is recaptured Heat normally lost through a south-facing building wall is recaptured by the ventilation air moving through the cavity behind the Solarwall and is returned to the building. Thus, Solarwall effectively increases the insulating value of the wall.
Indoor air is destratified Many buildings have poor air temperature distribution.
Warm air accumulates at ceiling level and cold air sinks to floor level. This condition, known as stratification, causes two problems. First, because warm air is furthest from where it is needed, extra energy is spent providing warmth at floor level. Second, heat at ceiling level is wasted when the warm air is exhausted directly or the heat is lost by conduction through the roof. This cool air enters the building at ceiling level, and its natural movement to floor level acts to mix and destratify indoor air.