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Geothermal Energy Basics (Text Version)

This is the text version of the video "Geothermal Energy Basics."

The earth is hot. [cat call] No, not like that. Like, physically hot.

With a temperature of nearly 11,000°F, the Earth's core is hotter than the surface of the sun

And humans have found a way to safely harness a small portion of that heat energy to generate power.

It's called geothermal energy.

The Earth is constantly releasing its heat. Sometimes, we even see it … in the form of hot springs or geysers, like Old Faithful at Yellowstone National Park.

Heat from the earth is one of the most reliable, oldest forms of energy … and by old, we're talking 4.5 billion years.

Ancient Romans, Chinese, and Native American cultures have used the geothermal energy for thousands of years—using hot mineral springs for bathing, cooking, and eating.

So, how do we capture Earth's incredible energy? There are a few ways.

We can tap into the consistent temperature located just a few feet into the ground to use the Earth like a thermos, heating buildings in the winter, and cooling them in the summer …

or dig deeper to access the Earth's heat. In some places in the Western U.S. and Hawaii, this heat is shallow (<3 km), but this heat is everywhere, no matter where you are on Earth—you may have to drill a little deeper!

These geothermal resources provide energy that can be used on both large and small scales.

A geothermal power plant uses heat to produce steam, which turns a turbine, which drives generators, and converts the power into electricity.

Or, the heat can be applied directly for various uses in buildings, roads, agriculture, industrial plants, and even homes.

In 2019, United States geothermal power plants produced 16 billion kilowatt-hours of electricity—all in the Western U.S. That's only a small fraction, less than a half percent, of the total U.S. utility-scale electricity generation … and there is so much potential! In fact, there is more than enough heat below the U.S. to provide all its needed energy.

So, why don't we use more? Geothermal is one of the least-explored sources of clean energy.

But with such a long track record, scientists continue to work on better ways to capture and use this clean, natural, renewable resource to be able to use it anywhere in the U.S.

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