Whenever I say “geothermal” in discussion, I always have to make clear which version of that technology I’m referencing.
One is the “Advanced” Geothermal, which uses cutting edge drilling techniques from the fracking industry to access heat buried deep in the earth’s crust – and I’ve posted recently on how rapidly that is progressing.
The other kind that might be more familiar to homeowners, which is shallow wells or trenches that access the stable temperatures just below the frost line that exist everywhere, and can be cheaply accessed to provide both heating or cooling.
The big barrier has always been the cost of drilling those wells or trenches.
Now, somebody claims to have solved for that.
Big if true.
Farther below, Jesse Jenkins of Princeton University suggests that the applications for cooling Data Centers, one of the toughest technical issues, could by itself be a paradigm shift.
A company called Dig Energy might have cracked that code.
Dig’s innovation: a rig purpose-built to drill geothermal boreholes with less noise, less water usage, and far lower cost than conventional drilling equipment.
Dig says its technology could upend this math, cutting the cost of drilling by up to 80% as compared to conventional geothermal drilling. The companies declined to share specific numbers, but Dig “put some early proof points out there that, from a cost and schedule perspective, they’re going to be very competitive in the market,” said Parker Mundt, a partner at Suffolk Technologies.
In the standard process, the borehole is drilled first, typically with a metal bit or compressor, and shored up along the way with a casing to prevent collapse before a heat exchange pipe is inserted.
Dig’s system, by contrast, uses a high-pressure nozzle that sprays water at 10,000 pounds per square inch to bore through soil and rock. The approach was explored by the oil and gas industry decades ago, but never gained traction because it didn’t increase productivity in those sectors, Madden said. She and her partners saw an opportunity to adapt the idea for geothermal and spent years honing the technology.
When Dig CEO Dulcie Madden first shared their plans and deck with me two years ago, as soon as I understood the dramatic reduction in borehole drilling costs they were poised to unlock, I knew that if they succeeded that, over time, this would simply become the best way to heat and cool every building everywhere.
No exaggeration there.
I immediately agreed to join Dig Energy’s advisory board. This is game changing technology. Cheap, fast, low-impact drilling of shallow geothermal boreholes transforms geothermal heat pumps from an expensive niche tool for well-to-do sustainability-minded customers into simply the most economic way to do space or water heating and cooling. Period.
If that doesn’t sound like a big deal, keep in mind: more than one-fifth of ALL energy consumption globally is used to for space heating and cooling (and even more for water heating/cooling).
Not to mention, it’s by far the most efficient way to cool data centers (and logistics cold chains!) and slash the scarce grid capacity devoted to data center cooling rather than compute (see https://docs.nlr.gov/docs/fy26osti/100780.pdf).
The total addressable market here is MASSIVE.
I LOVE the simplification of the process an material demands they came up with!
I hope this goes like gangbusters, and I hope enough state, urban and suburban governments see that they could benefit even more if the up-front cost structure was improved by setting up incentives for taking a district-heating approach wherever digging.
Share the dig cost across a set of property owners, there could also be (thinking as someone living in dense city environment with hard winters) use of the same system to supply some of that underground thermal energy to under-sidewalk heat distribution to reduce the need to melt or shovel the snow and ice each winter.
I’ve been on a few college campuses in winter where they’d built the sidewalks with the campus steam pipes running beneath. It sure helps.