As with passive solar heating, fans may be used to encourage this ventilation. Daylighting Daylighting is the use of sunlight to replace electric lighting in a building. There is no technology at the current time capable of storing sunlight for release at a later time. Daylighting is therefore most valuable in applications such as office buildings where most of the lighting demand occurs during the day. The use of daylighting has often been seen as contradictory to the need for keeping a building cool in the summer.
Sunshine streaming through a window provides daylight, but is also a source of heat.
While this heat is valuable in the winter, it can make buildings unbearably hot in the summer. Conclusions Passive solar energy has the potential to supply a large proportion of the energy needs for a properly designed building. Although retro-fitting a building to incorporate passive solar is possible, it is often fairly expensive. The best opportunity for using passive solar is in new construction. Before the proliferation of fossil fuels, architects routinely designed buildings to utilize available solar energy for heating, cooling and lighting.