Let me count the ways…first, the solar fan costs nothing to run. The electric fans are generally noisy and tend to wear out after only a few years of service. ..that’s three. Most electric fans, because they cost money to operate, are coupled with a thermostat. The thermostat turns the fan on when the attic temperature reaches a set temperature, usually 90 or 100 degrees…by that time you’ve lost the battle. How effective is a fan that is trying to cool a 100 degree attic with outside air that is probably 90 degrees. The solar fans come on in the morning when the sun hits the solar panel and begins to draw cool air through the attic. Our customers who had an electric fan in their attics and left it there after we installed the SRS solar powered fan, tell us the electric fans hardly ever come on…the solar fan does all the work. And don’t forget the solar fans are designed to work 12 months a year which means they operate summer and winter…but that’s another question.