As we discussed a few months ago, drilling for geothermal energy is a process that is fraught with complications. In June, startup AltaRock Energy announced plans to use a controversial method to drill for geothermal energy in an area called the Geysers, located in Northern California. But the company was criticized by the New York Times  for using a method of drilling known to have caused thousands of small earthquakes in Basel, Switzerland. And now the drama continues as AltaRock has announced that it is halting drilling operations in the Geysers. So what happened?
AltaRock isn't too forthcoming with the details, saying in a statement only that it "has encountered a number of physical difficulties" in the well as a result of "geologic anomalies particular to the formation underlying this well location." When I asked an AltaRock representative for specifics about the anomalies, I was told that the company can't release any more details.
Perhaps this has something to do with the aforementioned earthquakes? We may never know--AltaRock is already scouting out new well sites in the Geysers and elsewhere. With funding from Google and Kleiner Perkins Caufield & Byers, the pressure on for AltaRock to make its engineered geothermal systems (EGS) technology work.
AltaRock is one of the only companies working on EGS, but the technology has plenty of promise--according to MIT, it could potentially provide 10% of all power in the United States.
[AltaRock Energy (PDF)]