On a farm near Manchester, New Hampshire, a burst of muddy water signaled the promise of Dig Energy’s new approach to geothermal drilling. The five-year-old startup, operating in stealth until now, has unveiled a compact water-jet drilling rig designed to cut geothermal installation costs by up to 80%.
On Tuesday, the company announced it had raised $5 million in seed funding led by Azolla Ventures and Avila VC, with participation from Baukunst, Conifer Infrastructure Partners, Koa Labs, Mercator Partners, Drew Scott, and Suffolk Technologies.
Heating and cooling account for about a third of U.S. energy use, and as much as 40% in data centers. Geothermal could reduce HVAC energy consumption while saving grid operators billions. But high upfront costs have long kept adoption stuck at just 1% of buildings in the U.S.
Dig Energy’s co-founder and CEO, Dulcie Madden, alongside CTO Thomas Lipoma, believes their smaller, straighter-drilling rigs can overcome that barrier. Unlike massive truck-mounted rigs derived from oil and gas technology, Dig’s compact machines can maneuver into tight spaces like backyards and crowded commercial sites.
The company’s prototype has already proven capable of drilling through varied rock types while allowing boreholes to be placed closer together, a key advantage for developers. With its new funding, Dig plans to refine the rig, launch pilot projects, and sell units directly to drillers.
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“We shouldn’t have to require people to buy a $2 million rig,” Madden said. “Geothermal should be in 100% of buildings. It’s in 1% of buildings. So how do we close the 99%? It’s effectively an untapped market.”
