https://www.greenmountainenergy.com/why-renewable-energy/renewable-energy-101/geothermal/ While some renewable energy sources — like the sun, the wind, and water — can easily be seen and/or felt, geothermal (or simply “thermal”) energy comes from a more enigmatic source: the heat far below the Earth’s crust. For more than 100 years, steam from below the Earth’s surface has been used to generate power. From electricity generated through geothermal power plants to district energy systems that heat and cool buildings using an underground network of pipes, this alternative energy source has big potential. Now that’s deep! Check out this video to learn more about how geothermal energy works. Transcript: Renewable Energy 101 If you've ever observed an erupting volcano or the geysers at Yellowstone National Park, you've seen geothermal energy in action. The Earth's crust is made of rocks and water. Deep below that is a layer of hot, molten rock called “magma,” which is even hotter than the sun's surface. The heat just over six miles below the surface contains 50,000 times more energy than all the oil and natural gas resources in the world. Releasing a small amount of that heat in the right way can create electricity. A well drilled a couple of miles deep can capture the rising hot water and steam. That steam spins a turbine and a generator produces electricity. Geothermal is one of the least explored sources of renewable energy in the U.S., and most of us probably don't spend much time thinking about it. But since it's a pollution-free renewable source of energy that's consistently reliable — at least it has been for the past 4.5 billion years — maybe we should! About Green Mountain Energy: As the nation’s longest-serving renewable energy retailer, we’ve been on a mission to change the way power is made since 1997. By choosing our 100% clean, renewable wind and solar energy plans for their homes and businesses, Green Mountain customers have avoided more than 81 billion pounds of CO2 emissions to date — that’s like taking 8.6 million cars off the road for an entire year! But, we’re more than just an energy company. We’re helping our customers make a positive environmental impact, support a cleaner grid and green their carbon footprints with sustainable living solutions, renewable energy plans and the purchase of carbon offsets. And, our charitable program, Green Mountain Energy Sun Club®, has donated more than $10 million in grants to nonprofits for sustainability projects focused on renewable energy, energy efficiency, resource conservation and environmental stewardship. For more information, visit greenmountainenergy.com and gmesunclub.org. Together, we’re building a cleaner, greener tomorrow. More from Green Mountain Energy! Website: http://bit.ly/1IKvQId Facebook: http://on.fb.me/1Ovf9AV Twitter: http://bit.ly/1Qmn2dk Instagram: http://bit.ly/1g7xE2t © 2020 Green Mountain Energy Company. All rights reserved.