Скачать или смотреть Can Enhanced Geothermal Help Save Our Planet?

Enhanced geothermal systems, or EGS, involve advanced drilling methods for extracting heat from deep in the Earth to generate electricity and to heat buildings. Is this a clean and useful technology? I’m Mark Jacobson, Professor of Civil & Environmental Engineering at Stanford University to answer this. High-temperature heat from within the Earth is needed to generate geothermal electricity. Almost all geothermal electricity today is from conventional geothermal plants, where the heat is drawn from shallow underground heat reservoirs near volcanos, geysers, hot springs, and tectonic plates. Elsewhere, temperatures in the Earth naturally increase by about 25 degrees Celsius per kilometer of depth. So, drilling 3 to 8 kilometers is usually needed to obtain sufficient heat to generate electricity. The resulting EGS wells are drilled with hydraulic fracturing techniques borrowed from the oil and fossil gas industries. With EGS, two or more wells are drilled – at least one is an injection well for cold fluid to go down and at least one is a production well for hot fluid to rise. The fluid used is either contaminated groundwater, treated municipal water, industrial process wastewater, irrigation return water, storm water runoff, brackish water, or freshwater, often with ~1% by weight of chemicals added. The chemicals improve the fluid’s ability to expand and crack rock. The fluid heats as it flows through the cracked rocks. The hot fluid is then pumped through a production well to the surface, where the heat is transferred to a low-boiling-point organic fluid that evaporates. The hot vapor then generates electricity in a turbine before it is recondensed and recycled. Sufficient heat can be extracted from deep in the Earth with EGS to satisfy the world’s entire energy demand for all purposes upon electrification of most energy. About 25 percent of all land available worldwide may be suitable for EGS electricity generation. Because EGS electricity-generating plants recycle the gas used to generate electricity, they result in no emissions. Geothermal heat is also replenished naturally. As such, EGS is a clean, renewable technology that can help solve air pollution, climate, and energy security problems.


More information
Still No Miracles Needed: How Today’s Technology Can Save Our Climate and Clean Our Air
https://web.stanford.edu/group/efmh/j...

The Impact of Enhanced Geothermal Systems on Transitioning all Energy Sectors in 150 Countries to 100% Clean, Renewable Energy (available January 2026) https://web.stanford.edu/group/efmh/j...