Dig Energy Raises $5 Million to Unlock Cost-Competitive Geothermal Heating and Cooling

Manchester, N.H. – Dig Energy has raised $5 million in venture financing to advance its patented geothermal drilling technology, aimed at transforming building heating and cooling systems into cost-competitive, sustainable solutions. The round was co-led by Azolla Ventures and Avila VC, with participation from Conifer Infrastructure Partners, Suffolk Technologies, Mercator Partners, Koa Labs, Baukunst, and Drew Scott. The company has also secured support from Suffolk Technologies’ BOOST accelerator and the U.S. Department of Energy’s EPIC Prize.

Tackling Heating and Cooling’s Carbon Footprint

Heating and cooling represent 35% of global energy consumption, with fossil fuels dominating supply. While geothermal heat pumps are recognized as the most energy-efficient HVAC solution, adoption in the U.S. remains below 1%. A key barrier is drilling costs, as traditional rigs are designed for oil and gas, making them expensive and impractical for smaller-scale applications.

A Compact Drill Built for Geothermal

Dig Energy has developed a purpose-built, compact drill that replaces costly carbide bits with high-pressure fluid drilling, reducing borehole installation costs by up to 80%. This breakthrough enables geothermal to compete directly with fossil fuels and air source heat pumps without relying on subsidies or policy support.

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

Investor Confidence in Scalable Innovation

Investors see Dig’s drilling system as the missing link for mainstream geothermal adoption. Azolla Ventures’ Johanna Wolfson noted that pilot projects will demonstrate how the technology can transform HVAC markets. Avila VC’s Patricia Wexler added that the drill leverages existing supply chains, making it “ready to scale at exactly the right time.”

Toward Pilot Installations and Market Expansion

With the new funding, Dig Energy will advance from field testing to its first pilot installations, showcasing a pathway to decarbonize heating and cooling across residential, commercial, and municipal sectors. By lowering drilling barriers, the company aims to accelerate geothermal adoption worldwide.

About Dig Energy

Founded in New Hampshire, Dig Energy designs geothermal-specific drilling technology to make heating and cooling cost competitive with fossil fuels. Its compact system reduces drilling costs by up to 80%, unlocking the potential for widespread geothermal heat pump adoption. Learn more at www.dig.energy.