| The heat of the Earth makes up what is known | | | | 700 degrees Fahrenheit. When the water travels |
| as geothermal energy. When dust and gasses | | | | to the Earth's surface, it becomes hot springs or |
| from Earth mixed together 4 billion years ago, | | | | geysers. Mostly it stays trapped in fractured, |
| geothermal energy resulted. | | | | porous rocks called geothermal reservoirs. This |
| Inside the Earth at its core, some 4, 000 miles | | | | heat near the Earth's surface becomes a form of |
| deep, the temperature is estimated at about | | | | energy. |
| 9,000 degrees Fahrenheit. Geothermal energy has | | | | Hot water or steam from the reservoir exerts a |
| been used throughout history for bathing, relaxing, | | | | force that can spin a turbine connected to a |
| cooking and heating. It was thought by some to | | | | generator and produces electricity. The cooled |
| have healing effects and was used to treat eye | | | | water is then returned to the reservoir in order |
| and skin diseases. The first geothermal generator | | | | for it to reheat. Much exploration and testing |
| that produced energy was built in Lardarello, Italy | | | | needs to be done to determine where the |
| in 1904. The United States followed with their first | | | | geothermal underground waters are. When ideal |
| attempt at geothermal power in 1912 at The | | | | spots are located, drilling is done to create |
| Geysers in California. Today it is produced in | | | | production wells that bring the water to the |
| twenty-one countries around the world. | | | | Earth's surface for power generation in |
| Geothermal energy is located deep in the ground. | | | | geothermal power plants. |
| The heat at the core of the Earth has an | | | | Although the costs to construct geothermal plants |
| outward flow. As it moves, it is transferred to | | | | and geothermal wells are high, the cost of |
| surrounding rock layers called the mantle. As | | | | producing electricity is lower over time. The fuel is |
| temperatures and pressure increase, the rock | | | | reliable, stable and does not need to be |
| melts and becomes magma. The magma moves | | | | transported. The white smoke you will see over |
| toward the surface of the earth carrying the heat | | | | geothermal power plants is not smoke but rather |
| with it. If the magma reaches the Earth's surface, | | | | steam. During the process of operations it may, |
| it becomes lava. However, most of it stays below | | | | however, bring some hazardous gases from |
| the Earth's crust and heats rocks and water that | | | | underground. |
| surround it. These temperatures can reach up to | | | | |