Geothermal Is Too Expensive, But Dig Energy’s Impossibly Small Drill Rig Might Fix That

On a workplace adjacent Manchester, New Hampshire, I was precocious treated to a gusher of soiled water, not precisely nan benignant of point that astir startups will show a reporter. But for Dig Energy, nan mud is simply a feature, not a bug, of its compact drilling rig. 

The startup, which has been operating successful stealth for nan past 5 years, developed nan water-jet drilling rig successful an effort to make geothermal heating and cooling truthful inexpensive that it will displace fossil substance boilers and furnaces. The rig is cardinal to that, promising to slash drilling costs by up to 80%.

On Tuesday, Dig Energy emerged pinch $5 cardinal successful seed funding, TechCrunch has exclusively learned. The information was led by Azolla Ventures and Avila VC pinch information from Baukunst, Conifer Infrastructure Partners, Koa Labs, Mercator Partners, Drew Scott, and Suffolk Technologies.

From left: Vice President of Engineering Dan Jepeal, CEO Dulcie Madden, and CTO Thomas LipomaImage Credits:Dig Energy

Heating and cooling correspond astir a 3rd of each power usage successful nan U.S., and successful information centers, nan fig tin beryllium arsenic precocious arsenic 40%. Geothermal tin slash HVAC power usage while besides redeeming grid operators up to $4 billion annually. To thief stabilize its creaking electrical grid, nan U.S. needs to drill 6 cardinal feet of geothermal borehole regular done 2050, according to nan Oak Ridge National Laboratory.

But geothermal doesn’t travel cheap, astatine slightest not astatine first.

“In nan United States, geothermal has been 1% of building installations for decades,” Dig co-founder and CEO Dulcie Madden told TechCrunch. That’s contempt nan technology’s debased operating costs. “It’s really conscionable because upfront costs is so, so, truthful expensive.”

There are 2 main flavors of geothermal: Enhanced geothermal drills down thousands aliases tens of thousands of feet. Companies for illustration Fervo and Quaise that are drilling nan heavy are tapping very basking temperatures — usually successful nan hundreds of degrees — to make electricity. The other, shallow geothermal, which is what Dig is focused on, is usually constricted to hundreds of feet. At those depths, nan crushed maintains a accordant somesthesia twelvemonth round, which is cleanable for heating and cooling residential and commercialized buildings.

In shallow geothermal, pipes transportation h2o underground wherever it transfers power to aliases from nan earth. In nan summer, it dumps excess heat, and nan chilled h2o returns to nan aboveground to cool a building. In nan winter, it absorbs power to lukewarm it.

Installing nan crushed loop, arsenic nan underground piping is called, represents astir 30% of nan full costs of a ground-source power pump and is 1 of nan main reasons nan exertion remains much costly than accepted heating and aerial conditioning systems. Tackling those costs was precocious connected Dig’s list. 

“When we were getting started, we were like, tin we build a lower-cost drill?” Madden said.

Madden and her co-founder, hubby Thomas Lipoma, began exploring nan abstraction 5 years agone aft winding down their erstwhile startup, Rest Devices. They soon stumbled upon aged investigation describing really to usage h2o jets alternatively of accepted cutting bits to bore into nan Earth.

But while location had been plentifulness of investigation into nan technology, it still wasn’t fresh for premier time. “A batch of nan drilling exertion has trickled down from lipid and gas,” Madden said. Translation: It tends to beryllium large, expensive, and overpowered for thing for illustration geothermal astatine nan depths Dig is plumbing.

This achromatic shed is wherever nan earliest Dig Energy prototypes were designed and manufactured.Image Credits:Tim De Chant

Dig has spent years refining nan creation of its rig, drilling trial holes adjacent its offices successful New Hampshire. They’ve drilled done soil, gravel, clay, sand, and a scope of different stone types, including sandstone, limestone, granite, slate, and shale. The squad showed maine trial blocks of immoderate very dense stone pinch neat holes blasted done nan middle.

Today’s geothermal drill rigs tin do nan same, but they’re monolithic by comparison. The astir commonly utilized versions beryllium connected nan backmost of ample trucks. For easy accessible sites, they activity good enough. But they are incapable to compression done broadside tons into people’s backyards, and astatine crowded commercialized building sites, they inhabit precious free space.

While Dig’s prototype isn’t fresh for commercialized use, what I saw was substantially smaller than wide utilized geothermal drill rigs. The holes it drills are besides straighter than those made by accepted rigs. Together, those 2 specifications mean that Dig’s bore holes tin beryllium placed person together, a boon for immoderate developer. 

When it’s fresh for its first commercialized pilots — thing this seed information will thief execute — Dig’s rig will turn successful size slightly, but it won’t require nan large, double-axle trucks that presently predominate nan industry.

The institution is readying to waste nan devices to drillers, giving them different action for existing projects and perchance opening avenues to caller ones. Other companies are exploring nan technology, too. 

“We shouldn’t person to require group to bargain a $2 cardinal rig, it should beryllium thing that’s little costs wherever they tin get into nan business,” Madden said. “Geothermal should beryllium successful 100% of buildings. It’s successful 1% of buildings. So really do we adjacent nan 99%?” she added. “It’s efficaciously an untapped market.”