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Geothermal the next big alt-energy? One company thinks so

A Seattle firm's new project seeking to prove geothermal energy is safe and viable will have to overcome two obstacles: concerns over induced earthquakes and a need for a challenging amount of funding.

The Newberry Caldera

The Newberry Caldera U.S. Geological Survey

The Newberry National Volcanic Monument includes this lava butte.

The Newberry National Volcanic Monument includes this lava butte. glennwilliamspdx (Glenn Scofield Williams)/Flickr (CC)

Map of the Newberry Volano east of the Cascades in Oregon

Map of the Newberry Volano east of the Cascades in Oregon U.S. Geological Survey/Wikipedia

The Seattle-based company AltaRock Energy, along with Oregon company Davenport Newberry, is embarking on a project that is a longstanding dream of sci-fi nerds everywhere: creating energy by harnessing the heat found deep within the Earth.

This will be done through a new process called Enhanced Geothermal Systems, which AltaRock founder and president Susan Petty believes will yield more energy and prove more economic than previous methods of attaining geothermal power.

The potential is rich on the West Coast, where, as part of the Pacific Ring of Fire, a great deal of geothermal activity can be found within the Cascades. But first Petty and Davenport Newberry will have to overcome public concerns and fears over possibly structure-damaging micro-earthquakes, which a similar project in Switzerland caused in the recent past. That's the goal of AltaRock's project, which is a simulation of the EGS process, and will not actually have a power plant to produce energy with.

The go ahead for the demonstration was given by the Bureau of Land Management, which issued a Finding of No Significant Impact at the beginning of April.

In preparation for the event, Tacoma Pump & Drill, a small drilling company from Graham, will soon be drilling holes for seismological monitors to attain background data in the Newberry Volcano in central Oregon south of Bend. The volcano is not the protruding Mount Rainier fare, but is rather more akin to Yellowstone: shallow and wide, 20 miles in diameter, with magma bubbling not far beneath the surface. 

The EGS simulation, expected to begin in late July or early August, will start by pumping 24 million gallons of water at 800 gallons per minute deep into the volcano. In a process called hydro-shearing, the water will come into contact with hot bedrock, creating cracks in the earth and forming deposits, thus allowing more water to collect and heat up at once. Once boiled to perfection, the water will then shoot back up as steam to the surface through two more holes drilled on either side of the deposits, where the water’s heat energy and pressure will be used to power turbines and produce electricity.

A video posted on YouTube by AltaRock provides a visual representation of what this process will look like.

Hydro-shearing is not the same as the strangely similar sounding but much more notorious hydraulic fracturing, or hydro-fracking, which has garnered much media attention and criticism lately. Hydro-fracking shatters the rock, while hydro-shearing only slightly widens natural cracks by fractions of an inch. Additionally, the diesel and toxic chemicals used in the process of hydro-fracking can effectively poison ground water and possibly pollute the air. Hydro-shearing, on the other hand, uses mostly cold water to form the cracks, with some help from non-toxic, biodegradable diverters and tracers, which according to a study will have no significant environmental impact.

The greatest concern, and the greatest obstacle to progress, are earthquakes. Referred to as “micro seismic events” by AltaRock, the process could create miniature earthquakes that often gauge below 1 on the seismic scale, but could scale in as high as 3.5 or 4, according to a report prepared by URS Corporation, Seismic Hazards Group. It is believed to be unlikely that these events will be felt by people, but they will be picked up by sensitive earthquake equipment.

In Brasen, Switzerland, a similar project caused up to $9 million in earthquake damage to homes and other structures, though no bodily harm occurred, according to a story, "Deep in Bedrock, Clean Energy and Quake Fears," by New York Times reporter James Glanz. A government study concluded that the project would cost millions of dollars of damage each year were it to continue. Which it did not.

Earthquake concerns over the Switzerland project arose when AltaRock Energy first tried to start a project in California, which ultimately failed as a result of drilling problems.


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Comments:

Posted Mon, May 7, 12:11 p.m. Inappropriate

"Washington State Geologist Dave Norman said that the drilling involved would cause a high frontend cost, which could prove to be unattractive to potential funders."

Hydroelectric dams also involve a large front-end investment, but once built they can be operated at a profit indefinitely. It's hard to imagine that there is a greater barrier to entry in this field than there is to hydro power. It would be interesting to know if the earthquakes associated with this type installation are new and unique to the hydrothermal process, or if they are the result of relieving stress on existing faults and thereby mitigate against larger earthquakes in the future. If that's the case, the earthquakes would be a definite positive outcome.

dbreneman

Posted Mon, May 7, 2:11 p.m. Inappropriate

Impoundments behind dams are not indefinite, because they fill up over time.

Steve E.

Posted Mon, May 7, 3:41 p.m. Inappropriate

dbreneman, I should have clarified. From what I understand, the small seismic events are caused by the hydrothermal process, when the cold water hits the hot bedrock. Unfortunately, I've heard nothing of the possibility of larger earthquakes being mitigated by this.

Posted Tue, May 8, 9:11 a.m. Inappropriate

But, Steve E, indefinite is not eternal.

dbreneman

Posted Thu, May 10, 8:28 a.m. Inappropriate

@debrenaman

The micro earthquakes would not relieve significant stress in the ground. It takes thousands of M1s to release the stress of even an M4 earthquake.

And a minor correction - people would feel an M3.5 to 4 earthquake fairly distinctly, although it would likely cause no damage.

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