Deep Fission, Inc. (Nasdaq: FISN) is targeting commercial deployment as early as 2027 following a successful 100-foot borehole demonstration in Fort Myers, Florida. The company announced a collaboration with Youngquist Brothers, LLC on September 21, 2026, to evaluate drilling technologies for its underground reactor model. The partnership focuses on constructing large-diameter boreholes to house the Gravity Nuclear Reactor, a small modular pressurized water reactor designed to sit approximately one mile underground.
| Metric | Value | Context |
|---|---|---|
| Target Deployment | As early as 2027 | Projected timeline |
| Demo Depth | ~100 feet | Scale test |
| Borehole Diameter | 34 inches | Test site |
| Canister Size | 30 inches | Prototype |
The demonstration completed on September 3, 2026, involved lowering and retrieving a 30-inch full-size prototype reactor canister into a 34-inch borehole. The test reached a depth of approximately 100 feet using Youngquist's proprietary drilling equipment. This scale test focused on installation and retrieval mechanics, which is distinct from the full-depth drilling work intended for the collaboration. The math reconciles with the company's stated goal of placing reactors in boreholes roughly one mile deep, as the current test validates the mechanical interface before scaling to full depth.
Drilling Expertise and Safety Design
Youngquist Brothers brings decades of experience drilling large-diameter boreholes to depths exceeding 8,000 feet. Harvey Youngquist, CEO of Youngquist Brothers, noted that the company has refined large-diameter drilling methods since 1971. The collaboration aims to adapt these proven commercial methods to Deep Fission's nuclear application. Liz Muller, CEO and Co-Founder of Deep Fission, stated that working with an established commercial driller allows the company to advance its approach using existing field equipment rather than starting from scratch.
The Gravity Nuclear Reactor uses standard low-enriched uranium fuel and established pressurized water reactor technology. The design secures the reactor in a water-filled borehole, where surrounding rock and water provide containment and cooling. This approach is intended to simplify construction and enhance safety for scalable commercial deployment. Deep Fission is currently advancing its first reactor project in Parsons, Kansas, and was selected for the U.S. Department of Energy’s Reactor Pilot Program. The company aims to deliver low-carbon baseload power to utilities, industrial customers, and data centers. The collaboration is expected to continue as Deep Fission works toward its projected commercial timeline.