In Hawaii, the Puna Geothermal power plant sits about 21 miles south of Hilo on the Big Island on the Kilauea Volcano.

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The water originates near a lava flow 6, 000 feet below ground, passes through a nearby geothermal power plant and cools to just over 100 degrees Fahrenheit by the time it reaches the lagoon.

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The geothermal plant provides roughly 30% of the Big Island's power.

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