Solar Powered Attic Fan: An Overview of Energy Saving Features

The first Solar Decathlon, sponsored by the U.S. Department of Energy, was a showcase of solar innovation and building technology. The 14 collegiate teams used the sun to power every home appliance and to heat and cool the home — a key component of the competition.

Andrew Lee of Carnegie-Mellon University says, "Heating and cooling is typically the greatest amount of energy used in a home. That can be reduced with the right amount and type of insulation, as well as by sealing the home properly."

Some of the collegiate solar innovations showcased are:

• Auburn University's special water tanks. Part sculpture, part solar heating system, the water-filled glass tanks heat up during the day and release the heat throughout the evening.

Many of these innovations are already being used in residential homebuilding. Homeowner Alden Hathaway built a net-zero colonial-style home in rural Virginia, and enthusiastically shares information with those who want to undertake the same type of project.

Alden's home contains the following innovations and solar technologies:

• 4-kilowatt amorphasilicon solar array
  
• 2-kilowatt solar monocrystalline array
  
• Solar hot water system
  
• Passive solar features/design
  
• An inverter to switch collected energy from DC to AC
  
• Is grid-tied so that extra energy collected is credited by the local utility
  
• The installation of an attic fan that will reduce overhead heat and further reduce cooling costs.