Solar Energy

The oldest principle of solar architecture is building orientation, which involves positioning a building in a way that considers environmental conditions such as topography and ground cover as well as overshadowing from trees or structures. As a rule, a solar-friendly building's lengthwise axis should run east/west and the structure should be twice as long as it is wide. The structure also can be designed to naturally circulate air or incorporate cooling elements such as a solar chimney to help with ventilation.

In general, windows facing the equator should be equal to five to seven percent of the building's floor space. If heating is a concern, window area facing away from the equator should be minimized and insulated glazing with low-emissivity coatings should be used to maximize solar gain while reducing heat losses by 30 to 50 percent. In hot climates, low-emissivity coatings on the outside of window panes can be used to reduce and control solar gain.

Solar Vehicles

Development of a practical solar powered car has been an engineering goal for 20 years. The center of this development is the World Solar Challenge, a biannual solar-powered car race covering over 3,021 km (1877mi) across central Australia from Darwin to Adelaide. The race's objective is to promote research into solar-powered cars and teams from universities and enterprises participate. In 1987, when it was founded, the winner's average speed was 67 km/h (42 mph).[54] By the 2005 race, this had increased to an average speed of greater than 100 km/h (62 mph), even though the cars were faced with the 110 km/h (68 mph) South Australia speed limit.