In addition to a $6 million grant from the Energy Department, AltaRock had attracted some $30 million in venture capital from high-profile investors like Google, Khosla Ventures and Kleiner Perkins Caufield & Byers.
“Some of these startup companies got out in front and convinced some venture capitalists that they were very close to commercial deployment,” said Daniel P. Schrag, a professor of geology and director of the Center for the Environment at Harvard University.
Geothermal enthusiasts asserted that drilling miles into hard rock, as required by the technique, could be done quickly and economically with small improvements in existing methods, Professor Schrag said. “What we’ve discovered is that it’s harder to make those improvements than some people believed,” he added.
In fact, AltaRock immediately ran into snags with its drilling, repeatedly snapping off bits in shallow formations called caprock. The project’s safety was also under review at the Energy Department after federal officials said the company had not been entirely forthcoming about the earthquakes produced in Basel in making the case for the Geysers project.
— Running Aground - Geothermal Project in California Is Shut Down - NYTimes.com