Save Money with Geothermal You already purchased your property - why not use the free energy source just beneath the surface of your yard? A WaterFurnace geothermal system can distribute a staggering five units of energy for every one unit of electrical energy used. But what does that mean for you? It means you can condition your Charleston home for far less than your neighbors and friends. The equipment we install is the most proficient geothermal products in the industry today. Homeowners can grab a hold of savings up to 70% for heating, cooling, and hot water!