Did you know almost 90 percent of Icelanders heat their homes using geothermal energy? Ancient Romans used geothermal energy to heat their bathwater. Geothermal energy can also be used to generate electricity. As our energy needs grow, scientists and other innovators are seeking new energy sources that are efficient, sustainable, and environmentally friendly. In this book, you’ll examine both how we are using geothermal energy now and how geothermal power might fit into our energy future.