Save Money with Geothermal Free energy is 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 reclaims an phenomenal five units of energy for each electrical unit of energy used. But what does that mean for you? It means you can condition your San Antonio home for far less than your neighbors and friends. The equipment we place in your home is the most proficient geothermal products available. Homeowners can realize savings up to 70% for heating, cooling, and hot water!