Geothermal heating and cooling systems are gaining in popularity in the United States. They provide energy-efficient heating in the summer, by transferred heat energy from a few feet underground into the home, and cool your home in the summer by depositing heat energy from the home back into the ground. They manage this heat-exchange process by transferring the heat via a system of pipes, usually excavated and installed underground.
If you'd like one of the most efficient ways of heating and cooling your Indiana home, you can't do any better than a geothermal heat pump. These tap into the stable underground temperatures to deliver heated and cooled air. Temperatures above ground fluctuate a great deal, but below the surface of the soil, the temperatures are relatively stable. A heat pump doesn't use any fuel except for electricity and just exchanges or captures heat.