Numlock Sunday: Alexander C. Kaufman on the rise of geothermal

By Walt Hickey

Welcome to the Numlock Sunday edition.

This week, I spoke to Alexander C. Kaufman, who wrote Geothermal startup’s drilling breakthrough shaves ‘tens of millions’ off costs for his newsletter FIELD NOTES. Here's what I wrote about it:

Up until recently, for geothermal energy to work, you had to drill into a hotspot where there were large underground reservoirs of hot water. However, the new class of geothermal startups is pushing drilling tech to build subterranean furnaces. Some companies like Eavor are drilling a lattice of boreholes that connect at the bottom, forming loops through which cold water can be piped in and hot water can be piped out, generating power. Simultaneously drilling two parallel holes that intersect in hot bedrock is a steering nightmare, as GPS and electromagnetic signals don’t work at that depth. A new, long-awaited in-house drilling tool with equipment that communicates through magnetic signals just came fully online as of this week. This new t…