What is the difference between passive solar energy systems and active solar energy systems?
Passive solar energy systems use the architectural design, natural materials, or absorptive structures of a building as an energy-saving system. The building itself serves as a solar collector and storage device. An example would be thick-walled stone and adobe dwellings that slowly collect heat during the day and gradually release it at night. Another example of a passive solar energy system is a greenhouse. Passive systems require little or no investment of external equipment. Active solar energy systems require a solar collector (a device used to store energy) and controls linked to pumps or fans that draw heat from storage as necessary. Active solar systems generally pump a heat-absorbing fluid (air, water, or an antifreeze solution) through a collector. Collectors, such as insulated water tanks, vary in…