EarthGrid’s Plasma‑Powered Tunnel Borer Sets New Benchmark for Underground Infrastructure

In a California quarry, a team of engineers watched as EarthGrid’s latest tunnel‑boring machine (TBR) sliced through three metres of granite in a single January test. The machine, described by founder and CEO Troy Helming as “like igniting a rocket,” uses three plasma torches mounted on a rotating head to generate a super‑heated plasma stream reaching 27,000 °C—far hotter than the Sun’s surface.

Helming explained that the plasma creates a violent vortex inside the tunnel, which sucks away debris that sometimes behaves like molten rock. The result was a clean, cigar‑shaped bore that left the surrounding granite largely intact.

Although the machine over‑bored slightly to the top and left of the intended tunnel, Helming’s team plans to adjust the vortex to spin in alternating directions every five minutes, a tweak that should correct the deviation. The company aims to bring the TBR into commercial service as early as next year.

The technology arrives at a time when demand for undergrounding—moving power lines, fibre optics, pipelines, and data centres below ground—is rising. The Russia‑Ukraine conflict has highlighted the vulnerability of above‑ground infrastructure to drone attacks, prompting engineers to seek more resilient solutions.

EarthGrid has already attracted interest from utilities and telecom firms looking to bury cables, as well as from energy companies considering underground pipelines for water, natural gas, and ammonia.

One ambitious project under consideration involves constructing tunnels for an underground freight‑distribution system around airports and warehouses, a move that could reduce truck traffic.

Beyond utilities, the trend toward subterranean data centres is gaining momentum. Trentino DataMine, for example, recently completed a data centre in a 100‑metre‑deep cavern in the Dolomite Mountains of Italy. The naturally cool environment cuts cooling costs and energy use, making underground data storage increasingly attractive.

As the world seeks more secure, efficient ways to protect critical infrastructure, EarthGrid’s plasma‑driven TBR could play a pivotal role in reshaping how we build underground.