Steam

Although most energy in the United States is produced by fossil-fuel and nuclear power plants, hydroelectricity is still important to the Nation, as about 7 percent of total power is produced by hydroelectric plants. To create hydroelectric power huge...
Yes, but not very much. In 1995, power produced by using the earth's steam, called geothermal power, totaled about 6,100 gigawatt hours, which is about 0.2-percent of the Nation's total power production. Only about 59 million gallons per day of water was...
Refer to the Illustration. Heat and volcanic gases from slowly cooling magma rise and warm the dense salty water that occupies fractured rocks above the Yellowstone magma chamber. That brine, in turn, transfers its heat to overlying fresh groundwater,...