Dig Energy – Making geothermal heating and cooling competitive with innovative drilling tech

While high-temperature geothermal for power generation tends to get most of the media attention, shallow geothermal actually holds the key to supplying a major energy requirement globally – heating and cooling. In response to this, Manchester, New Hampshire-based Dig Energy has developed a compact, purpose-built geothermal drilling system that aims make ground-source heating and cooling practical and more affordable for the built environment.

Recently backed by a $5 million venture financing round co-led by Azolla Ventures and Avila VC, with participation from Conifer Infrastructure Partners, Suffolk Technologies, Mercator Partners, Koa Labs, and and preseed investors Baukunst and Drew Scott, Dig Energy is now preparing for pilot installations that aim to prove the scalability of its technology in real-world conditions.

Unlocking the promise of shallow geothermal

Heating and cooling make up about 35% of global energy consumption, which is largely dominated currently by fossil fuels. Geothermal systems, which leverage the earth’s stable underground temperature, have long been recognized as the most energy-efficient way to regulate indoor climates. Yet despite their promise, geothermal heat pumps remain stuck at roughly 1% adoption in the U.S., largely due to the high cost of drilling.

“The heat beneath our feet is abundant, reliable, and always on,” said Dulcie Madden, CEO and co-founder of Dig Energy. “Our purpose-built, reliable, robust drill finally unlocks the most efficient on-site source of heating and cooling for buildings. By making geothermal simple, scalable, and cost competitive, we can deliver true energy independence to buildings everywhere.”

Dig’s approach tackles the core bottleneck in geothermal deployment: drilling costs. Instead of relying on oversized rigs, Dig Energy has engineered a geothermal-specific system that reduces drilling costs by up to 80%, cuts the equipment footprint by 90%, and operates 50% more quietly than conventional rigs.

Geothermal drilling in urban environments

Traditional geothermal drilling rigs have long been limited by their size and impact, restricting installations in dense neighborhoods and urban settings where space is at a premium. Dig Energy’s compact, low-noise drill rig addresses these challenges. The purpose-built drill uses high-pressure fluid drilling instead of traditional carbide drill bits. The result is a drilling solution that reduces costs by up to 80%.

“Our technology is designed to fit and function in a wide range of environments, including densely populated areas,” explained Madden. “Because it’s significantly smaller and quieter, it enables geothermal installations where traditional rigs simply can’t go—like city blocks, school campuses, and commercial developments.”

The rig’s design also leverages existing materials and supply chains, ensuring scalability without the need for specialized or hard-to-source components. Its high-pressure fluid drilling system eliminates the need for costly carbide drill bits, further driving down costs and simplifying logistics.

“Dig’s deceptively simple drill leverages an existing supply chain and proven materials to tackle drilling cost – the single biggest barrier to geothermal adoption,” said Patricia Wexler, founder and General Partner of Avila VC. “They’ve built a proprietary solution from the ground up that is ready to scale at exactly the right time in the energy market.”

Pilot project and scaling up

With the latest infusion of venture funding, Dig Energy is now transitioning from field testing to pilot installations. These projects will demonstrate how the technology performs in diverse soil and building conditions while validating its potential to expand geothermal access across new market segments.

“The financing will help us grow our engineering and technical teams while deploying pilot projects that test our technology in real-world environments,” Madden said. “This will be a crucial step toward full-scale commercialization.”

Dig Energy plans to start with commercial-scale installations, targeting building and district-scale heating projects where the economic and environmental impact will be most immediate. However, the company also aims to drive costs down enough for residential adoption, enabling geothermal systems for individual homes. Ultimately, the broader vision is to transform heating and cooling everywhere, enabling full electrification of heat, high-efficiency cooling, and accelerating the transition to affordable, clean energy.

Raising the tide for all geothermal solutions

Beyond technology development, Dig Energy is also committed to raising public awareness about the potential of geothermal energy. Madden notes that the industry continues to suffer from persistent misconceptions: that it’s “dirty, expensive, or only viable in certain regions.”

“Our awareness campaign is about reframing geothermal as what it really is – a clean, affordable, and reliable solution for heating and cooling,” she said. “As energy prices rise, more people are recognizing that geothermal can be a cost competitive solution, in recent years because of tax incentives, and soon because Dig can slash the cost of drilling. Our awareness campaign aims to raise the tide for all geothermal solutions and highlight the broader benefits of clean, efficient, heating and cooling.”

With its technology’s potential to redefine cost structures and expand deployment possibilities, Dig Energy aims to contribute significantly towards mainstream geothermal adoption. By enabling scalable, low-impact drilling, the company is helping to make the most efficient form of heating and cooling accessible to more buildings, communities, and households.