You have “geo,” meaning earth, and “thermal” meaning heat. Together, you have “geothermal,” another word for super hot earth. Where and how does earth get so darn hot?
Magma Heats Things Up
Planet Earth’s center contains melted rock called magma. This rock is as hot as the surface of the sun. We live on the outermost layer of Earth called the crust. The Earth’s crust can be thick in spots, or very thin.
Water Gets Steamed
In some places, magma comes so close to the Earth’s crust that it can heat pools of water above it, turning them into hot springs and geysers. Sometimes magma, in the form of lava, actually oozes out through cracks in the planet’s crust.
When rainwater gets into these cracks it immediately heats up the water, producing steam. We can capture steam and hot water created by these underground molten hot rocks using pipes drilled into the Earth’s crust. This steam can heat homes and buildings, or is pumped to geothermal power stations where it operates turbines that turn it into electricity.
Where to Go Geothermal
Geothermal energy can be found heating pools in South America, Iceland, and at Yellowstone Park in the U.S. It can also be found on islands where there’s a lot of volcanic activity, like in the Hawaiian Islands or the Azore Islands in Portugal.
Geothermal Pros and Cons
The best things about geothermal energy are that it’s renewable, since heat is always being produced inside the Earth, and that it doesn’t create any greenhouse gases. The down side to geothermal energy is that there are not many places on Earth where the crust is thin enough to access this energy. It’s also difficult to transport geothermal energy away from where it’s created.
There definitely are places, like volcanic Islands, where you can’t beat this kind of non-polluting, renewable power. So keep on rocking it, geothermal energy!