Until now, geothermal technology has only been used on a small scale to produce power. But with major new projects now underway, deep geothermal systems may soon begin making a significant contribution to the world’s energy needs.
Ultimately, thanks to unusually hot rock close to the surface and existing infrastructure from oil-and-gas production, the Cooper River basin alone could produce about 10,000 megawatts of electricity — enough to replace 20 large coal-fired power plants, says geologist Doone Wyborn, Geodynamic’s chief scientist. That’s just a taste of the potential that this technology, known as enhanced geothermal systems, holds for Australia and the world, according to Wyborn.
In the US, researchers estimate that for just $1 billion invested over 40 years — the cost of one large coal-fired power plant and a fraction of the cost of a nuclear power plant — 100 gigawatts of clean, dependable geothermal power could be developed in the United States alone.
The Geysers geothermal power plant in California is the world’s largest.
But deep geothermal power — water pumped down to the hot rock, heated, and then brought back to the surface to turn turbines for electricity — is increasingly being eyed as an enormous potential source of pollution-free energy.
But some analysts and scientists say that deep geothermal power, accessed through so-called “enhanced geothermal systems” (EGS), could contribute far more to America’s — and the world’s — energy grid.
At present, geothermal power delivers a kilowatt-hour of electricity for somewhere between 10 cents and one dollar, depending on the depth of the hot rock and the As much as 5 percent of U.S. power could come from geothermal by 2050, according to government estimates.
Today, The Geysers, the largest geothermal power plant in the world, produces enough electricity for 725,000 homes.
The more than 1 gigawatt of geothermal power currently produced globally — from California to Iceland to the Philippines — relies nearly exclusively on such natural outpourings of the earth’s heat.
Already, there are more than 3,000 megawatts of geothermal capacity in the United States – the bulk of it at the The Geysers – and as many as 100 new geothermal power plants are proposed for promising sites.
The researchers estimate that for just $1 billion invested over 40 years — the cost of one large coal-fired power plant and a fraction of the cost of a nuclear power plant — 100 gigawatts of clean, dependable geothermal power could be developed in the United States alone.
Once in place, geothermal power plants produce electricity nearly all the time, according to Dennis Gilles, senior vice president for geothermal at The Geyser’s owner, Calpine.
Some more background on geothermal energy. Last year, the Hawaii Electric Light Company (HELCO) announced that it would invest more time and money in exploring promising geothermal sites throughout the state. As petroleum-based fuels get more expensive and harder to extract, geothermal could provide a basic energy "cushion" for Hawaii at a reasonable cost. Aloha, Russ
See on e360.yale.edu