Save Money with Geothermal Free energy is just sitting there waiting to be used and it's only several feet below the surface of your backyard. What are you waiting for? A WaterFurnace geothermal system pulls an astounding five units of energy for each electrical unit of energy used. But what does that mean for you? It means you can condition your Southwest Michigan home for much less than your neighbors and friends. The equipment we put in your home is the most efficient geothermal products available. Homeowners can realize savings up to 70% for heating, cooling, and hot water!