For centuries the sun has been used as an energy source. In this module, you will learn about several important uses of solar energy. Most new homes being built today are designed to be energy efficient and many include special features to utilize solar energy for heating and cooling. Recently there has also been a great deal of interest in designing solar powered vehicles in order to reduce gasoline consumption as well as air pollution. Less expensive and more efficient solar cells are bringing us closer to the day when it will be common to see solar vehicles on the road.