Two high-profile geothermal projects in the U.S. and Europe were both permanently halted late last week, after federal officials in both countries questioned their safety and propensity to cause earthquakes. Projects in Basel, Switzerland, and in northern California were both abandoned, raising questions about the danger of purposefully cracking open the Earth to extract its heat.
The California project, operated by a firm called AltaRock, had been halted since September after the company ran into repeated snags with a drill. The project, about 100 miles north of San Francisco in an area called The Geysers, had also been under a U.S. Department of Energy review, according to the New York Times.
The Swiss project had been on hold since late 2006, when it caused earthquakes in the city of Basel, doing about $9 million in mostly minor damage to homes and businesses.
Both projects used an "enhanced geothermal" system, which works by fracturing bedrock and circulating water through the cracks to superheat it and produce steam. The steam would be used to spin turbines in a power plant.
Both projects were based in areas with a history of seismic activity, whether it was earthquakes, geysers, hot springs or fumaroles (steam vents). Those are associated with vents or cracks in the bedrock deep beneath the Earth's surface. The Basel and AltaRock projects aimed to force water underground to open new cracks. Additional water would then be pumped underground, where it would be superheated and turned into steam. Drilling into sandstone also releases water, which turns to steam, too.
Power companies already use shallow steam beds and fumaroles to generate small amounts of electricity; The Geysers is the world's largest dry-steam geothermal steam field, and at its peak in 1987, it served 1.8 million electricity customers, according to the Energy Department.
Geothermal energy can also be used to heat and cool homes; geothermal heat pumps involve circulating fluids at shallower depths to be passively warmed by the Earth's heat. But for geothermal energy to be used as a major power source, companies have to tap into the heat at much deeper levels. The fracturing process is one such method.
By its nature, fracturing causes earthquakes, but most of them are small enough to go unnoticed -- except when they aren't.
The Swiss project caused a 3.4 magnitude tremor Dec. 8, 2006, and although no one was hurt, it caused enough damage -- and fear -- to stop the drilling. What's more, the initial tremor was just the beginning. The region experienced 3,500 additional quakes in the following year, according to the Times. Most were small, but at least three more were above magnitude 3, the Times reported.
A Swiss government study announced last week that the project, which cost about $60 million, was likely to cause earthquakes that would do several millions of dollars in damage each year. Residents could expect between 14 and 170 quakes over the 30-year life of the project, though most would be minor.
American officials have not yet finished a study on AltaRock's Geysers project, where the company is now removing its drill rig. AltaRock had problems reaching the required depths at the site; drill bits repeatedly snapped off in shallow formations called caprock, the Times reported. The Geysers project had won a $6 million grant from the Energy Department along with about $30 million in private investment from firms including Google, according to the Times. The company is turning its attention to another project in Oregon.
Despite the setbacks, the Energy Department considers geothermal power a potentially rich, clean replacement for fossil fuels; the department is still working on a draft National Geothermal Action Plan, and invested more than $400 million in geothermal projects just this year. Several other enhanced geothermal projects have also received federal financing, including one in Idaho, operated by the University of Utah; one in Nevada; and another in California, a few miles from AltaRock's site.
As for the content of the article: too bad about these setbacks. Hopefully we'll still be able to use the tech safely.
Why don't they drill in the ocean where we have water and geothermic activity already together. Unless those earthquakes they produce cause tsunamis.
This article generates an incorrect view of tha facts concering the facts of these EGS projects. The AltaRock project was halted due to drilling related problems of entering a pre-existing hole and not as inferred in the first sentence to unsafe conditions nor a concern of generating an earthquake. The AltaRock project did not raise concerns of "craking the earth" to mine heat. The Basel project has not been proven to be the source of the refereneced earthquake. It is my opinion that the article appears to lack all of the facts concenring these proijects, appears uninformed about EGS, and has made statements that have not been completely nor properly researched and / or understood. The article appears to me to generate a very misleading view of these early efforts to better understand EGS which may eventually prove to be the only reliable base load energy resource large enough to solve our energy problems. Please check your facts before you opine on this subject.
Hey everybody, I've got it!
Let's stop burning so much darn oil and coal!!!
You know, that idea is so CRAZY it just might work...
I hate how it seems that the information from this article has been made up and no supporting link for the article was provided.
Yes, Stavatti, I agree with you, and did you also notice that those geothermal power plants that caused earthquakes were intentionally built over natural faults? You would think that common sense would tell those morons...don't do that. There are fourteen states in the U.S. that have geothermal power plants and none of them are built over a fault and none of them have caused an earthquake. Oil wells are drilled deeper than geothermal holes and the oil wells do not cause earthquakes, and if they do, you do not see them being shut down for fear of more earthquakes. This article is defently a pro oil, coal, and natural gas article designed to scare the illiterate. Norway has been using geothermal for over eighty years and they have had no earthquakes. Geothermal is and always will be the safest, cleanest, and cheapest source of producing a never ending sorce of power.
Brilliant, JamesDavis,"This article is defently a pro oil, coal, and natural gas article designed to scare the illiterate." An article to scare the illiterate - that will surely work. Maybe it will scare the ignorant as well.
That aside, they drill on faults, because that lets you get the most heat for the least drilling. Also, it isn't so much the drilling that causes problems, but the flashes. The water vaporizing at that heat creates outward pressure as well as upward pressure, which can cause already stressed faults to crack. It is possible that some of those 3500 quakes were not "earth quakes" from shifting earth, but "earth shakes" from the flashes (much like how heavy machinery can create false rictograph reports).
Geothermal, when done on non-seismic lang, creates much less power, but in a far safer and more sustainable manner. Of course, massive power plants with huge outputs would be cheaper, but less sustainable (replacement costs, etc).
So a magnitude 3.4 earthquake in Switzerland cause millions of dollars in damage. They must have some pretty shoddy construction in Switzerland.
To "popular scientist" - Sorry, that is not going to happen any time soon.
If Cap & Tax passes congress, I personally will set-up my own incinerator and burn everything I can get my hands on to generate electricity cheaply. Grass clipping, plastic, paper, rubber, you name it. I've already designed and costed it out and it is very economical. I should be able to recoup my investment in about ~7 years based upon the projected cost increase of energy. The real kicker is that most of the system is off the shelf. I just needs to be combined.
The illiterate can't read. Cap and trade is communism. There's more oil than world leaders are letting on. And Yellowstone will make a crater the size of the US by the time POTUS steps down as supreme commander of the world.
Hey 'popular scientist' - If you're buying I'll take solar, geothermal and a couple Tesla electric cars, otherwise who can afford not to burn cheap oil or coal for energy these days? Cost is the main factor in the midst of this recession. Gotta love all the silver bullet solutions that don't really take anything into consideration though.
Here's a better idea - why don't all the wealthiest Americans start a huge financial Energy Fund to help assist less wealthy and poor Americans convert to efficient renewable energy (like the Copenhagen summit). Sounds a little socialist, but I'll be waiting patiently for the assistance by my mailbox - in the winter cold.
Thank you for the information that your your article provides! The New York Times articles that have reported on this project have been very informative and are a good link if you want more info on the science related to this type of energy production and the earthquakes geothermal has been causing in our area. I am a neighbor of geothermal on High Valley Road in Cobb Mountain, in an area north of the Anderson Springs community. My community has been significantly impacted by the illegal activities of our neighborhood geothermal power plant, Bottle Rock Power LLC. We are all very concerned with the air and water pollution from H2S, and the array of hazardous chemicals the neighborhood is getting exposed to, caused by geothermal operations. Living next to a geothermal operation is like living next to an active volcano, the ground shakes, the air stinks with unknown acrid chemicals; you don't know how it is affecting your health for the short or long term. If they really were a clean green energy source, I wouldn't be commenting but it just isn't so....