Geothermal start-up AltaRock suspends drilling

A new company pursuing an advanced geothermal energy technology has had to suspend its first attempt to drill a deep well in Northern California.

AltaRock Energy on Wednesday said it ran into problems during drilling for a demonstration project, "resulting from geologic anomalies particular to the formation" at the Geysers Geothermal field.

The project, said to be budgeted at $17 million, was partially funded by a Department of Energy grant given to several companies to explore the viability of enhanced geothermal systems. Sausalito, Calif.-based AltaRock was funded by Google and venture capital company Kleiner Perkins Caufield & Byers.

(Credit: AltaRock Energy)

Although technical difficulties are normal in drilling projects, the progress of AltaRock is significant because it is one of few companies pursuing enhanced, or engineered, geothermal systems. It's a technology that holds great promise but that has raised safety concerns.

Traditional geothermal power draws on naturally occurring underground hot-water reservoirs to make electricity. With enhanced geothermal systems, wells are dug a few miles underground, and rock formations are fractured. Then water is injected into the wells, heated by the rock, and pulled back up. That hot water is converted to steam to turn an electricity turbine.

A Massachusetts Institute of Technology study two years ago found that using this enhanced method of geothermal power generation could supply 10 percent of the electricity in the United States. It could also be done in a wide variety of locations, rather than just the limited number of locations that have traditional geothermal resources.

But an article in The New York Times in June raised questions over the safety of enhanced geothermal systems, due to the deep drilling. In one test in Switzerland, drilling from a geothermal project caused earthquake tremors, causing the project to shut down. The Department of Energy and the Department of the Interior's Bureau of Land Management will not allow AltaRock to fracture rock before a review which is still pending, according to the Times report.

In its statement, AltaRock didn't offer many details on why it suspended drilling but said it is evaluating other locations to build a demonstration facility, including other spots at the site where it had been working.

[doubtthat]

Aren't we going to cool the earths core doing this? It's bad enough we have global warming going on now we will have core cooling. This can't be good. ;>)

[MD_Willington]

No it will not cool the interior of the earth.

[T_Hoff]

@MD_Willington

Sure it will. Initially this will not be measurable, but eventually we'll have to drill deeper and deeper to sustain thermal energy production.

When we started dumping our waste into the oceans, we rationalized that as well and told ourselves that it was a drop in a very large bucket. Given a large enough scale and decades of this practice, it has had a significant impact.

[Jim1900]

The earth's core has been cooling for 4.5 billion years. Volcanoes are orders-of-magnitude more effective at it than anything we can do. On the other hand, global warming could end civilization as we know it in a couple of hundred years. Even more worrying, we could get to the point of no return where the positive feedback effects cause the warming to accelerate in a few dozen years. Maybe we are there already. Significant cooling of the core is the least of our concerns, and probably won't even be seen by the human species, much less our civilization.

[jaguar717]

It astounds me that so many people fail to understand basic orders of magnitude.

Drop in the bucket? How bout drop in a lake?

[texaslabrat]

the thread under this post represent various degrees of reality. The answer is "yes" some cooling will occur...but as others have pointed out the macroscopic effect won't even begin to be measurable. In fact the core is constantly creating *new* heat via radioactive decay which largely renders even this infinitesimal effect moot on a global scale. That said, the *local* cooling at the place where the water is being pumped into will be more substantial, and at some point, when the excess latent heat in the "reservoir" has been exhausted, there will be a limit to how much steam can be produced per unit time which is related to the heat flux into the region (ie the rate at which the heat removed by the water is replaced via conduction through deeper rock from the core). I don't know the exact numbers involved, but this effect necessitates a rather large reservoir be created to ensure a large amount of conduction maintains the heat flux over the long-term. And this is where the safety concerns are...a large reservoir means a large amount of fractured rock, which potentially means a higher chance of man-caused tremors and the like occurring depending on the surrounding geologic formations.

[inachu1]

They really are a green company but nobody knows this better than me.
They will get lic. from whatever state to test for potential areas to build and will make all the paper legal work if your house sits over one then you can not transfer owndership of your house to your children in your will.

This happend to my family and my grandparents house is now destroyed either to make electricity or as a bath house row for tourists.

People really know how to kill the neighborhood.

[bschmock]

@ doubtthat

That's what I was thinking.

Also what about the water that's converted to steam how much water loss is there? Are the using fresh water? BC people seem to forget that we don't have a limitless supply of fresh water.

[texaslabrat]

If done correctly, such systems should be closed-loop so very little water will be lost in the process.

[coconutgirl1]

do people ever bring up what happened at the geothermal plant on the big island. i know there was one "explosion" that blew the front door off my friend's home, which is within 1/2 mile of the plant. the frame of the house is still crooked.i think it was hushed a bit and the homes around the plant were never compensated. also, ud rather be upwind from them if you live near one.

[essfilms]

I'm not sure why you'd build one of these in California..one of the most active Seismic zones in the US. Try the Granite state intead, maybe? Solid!

[carlhage]

Geyserville is a volcanic hotspot where magma comes close to the surface. It already the major source of geothermal power from wells drilled into naturally produced steam. Unfortunately, the wells are running dry so production has been declining (from overdrilling). This enhanced geothermal project was to inject water into the ground for conversion to steam rather than rely on natural groundwater. Where ever you drill, your best bet is to drill into a volcanic hotspot. They are related to the areas of moving plates-- the main source of earthquakes, but usually not exactly at the same spot.

[highguard01]

Nikola Tesla has the cure but he is dead so you will have to look it up whatever your doing wrong.
im thinking maybe you should try to use smaller diameters and procure less energy there is a magnetic option here at some point you may or may not understand me so just ask highguard01
ok plastic cylender shape magnetic valve shape oil goes on magnet magnet pumps air to turbines
which make good pumps and turbines make good power honestly dont think steam dependancy is the issue think its what your not using since steam could be used as a starter you just need to slow down natural streams and keep them more full with water the end