Segal Geothermal
Drill to the heat that never stops.
Deep and supercritical geothermal. Closed loops where rock allows, engineered reservoirs where it doesn't, and next-generation drilling toward depths where one well does the work of dozens.
Tap the mantle.
The hottest, most reliable reactor on Earth is the Earth. Four thousand kilometres down, the mantle holds more thermal energy than civilization could spend — and it never cycles, never sets, never runs out of fuel. The constraint was never the heat. It was reaching it, and reaching it cheaply. Segal Geothermal engineers the path down: closed loops where rock allows, engineered reservoirs where it doesn't, and next-generation drilling toward supercritical depths where a single well does the work of dozens.
Past the supercritical point of water — about 374 °C and 22 MPa — the working fluid carries several times the enthalpy of conventional geothermal steam, so a supercritical well delivers far more power per metre drilled. Reaching those conditions means going deep and hot, which conventional rotary drilling does slowly and expensively in hard, hot rock. The heat is effectively infinite; the cost-per-metre at depth is the entire economic question.
We pair closed-loop conductive systems (AGS) — sealed pipe, no fracturing, sited anywhere — with enhanced geothermal systems (EGS) — engineered fracture networks in hot dry rock — and invest in directed-energy drilling (millimetre-wave gyrotron rock-melting and plasma-spallation) to reach mantle-adjacent temperatures where the economics invert. A supercritical well also flows brine rich in lithium and silica, so the same borehole that makes firm power can hand a mineral stream to Segal Resources instead of a mine.
- ~90%+
- Capacity factor — firm, 24/7, weather-immune— target
- >374 °C
- Supercritical threshold we drill toward
- <1%
- Surface footprint vs equivalent solar/wind per firm MW— engineering target
- By-product
- Lithium & silica recovered from brine, not mined
SIMULATE
Subsurface twin — geology, heat, and live telemetry.
DRILL
Deep, mantle-adjacent boreholes; AGS or EGS as rock allows.
PRODUCE
Supercritical working fluid — >374 °C, max enthalpy per metre.
CONVERT
sCO₂ and steam turbines to firm, dispatchable power.
CLOSE
Closed loop, managed drawdown, lithium & silica co-production.
Subsurface thermal & reservoir simulation
A living subsurface twin fuses geology, thermal models, and live drilling telemetry to predict thermal drawdown and well life before committing a metre.
Closed-loop (AGS) conductive harvest
Sealed pipe draws heat by conduction with no fracturing — geographically unconstrained, low induced-seismicity, sited where the grid needs it.
Enhanced geothermal systems (EGS)
Engineered fracture networks open hot dry rock to circulation where natural permeability is absent — the workhorse for most of the continent.
Supercritical well design
Wells targeting >374 °C / >22 MPa working fluid, where enthalpy per metre — and power per well — steps up sharply.
Directed-energy / millimetre-wave drilling
Detail on directed-energy / millimetre-wave drilling is gated under U.S. export-control rules. Verified partners can request access — we confirm jurisdiction and eligibility before sharing.
Request accesssCO₂ & superheated-steam conversion
Supercritical-CO₂ and steam turbine cycles matched to wellhead enthalpy, converting deep heat to dispatchable electrons.
Lithium & silica co-production
Direct extraction of lithium and silica from production brine — by-product minerals recovered, not mined, handed off to Segal Resources.
Drilling deep into hot, hard rock fast and cheap is the unsolved variable — bit wear, wellbore stability, and cost-per-metre at depth. The heat is effectively infinite; the engineering is the entire game. Directed-energy drilling is a research bet, not a product, and we mark it as one.
Subsurface Twin
Reservoir + thermal-front simulation fused with live drilling telemetry; predicts thermal drawdown and well life over decades.
- Coupled thermal-hydraulic-mechanical reservoir model
- Live drilling telemetry assimilation
- Thermal-front and drawdown forecasting over field life
- Induced-seismicity risk surfaces for EGS
Brine Ledger
Auditable accounting of lithium, silica, and mineral co-production per well — the book that proves by-product recovery, tied into Segal Resources.
Closed-Loop Thermal Bore
Conductive harvest validated against the subsurface model.
Bench and thermal test bore demonstrating closed-loop conductive heat harvest, with measured output matched to the subsurface twin's prediction.
Supercritical Wellhead Pilot
Instrumented hot-rock loop measuring enthalpy vs depth.
An instrumented loop into hot rock measuring the enthalpy-versus-depth curve that sets supercritical well economics — data over assumption.
Directed-Energy Drilling Demonstrator
Millimetre-wave penetration rate in basalt analogue.
A research demonstrator measuring millimetre-wave penetration rate against a basalt analogue — the bet that could collapse cost-per-metre at depth. Explicitly a bet.
Firm Geothermal-to-Grid
Dispatchable baseload onto a live interconnect.
Reference engagement: a well and conversion plant delivering firm, dispatchable baseload onto a live interconnect.
Directed-energy drilling penetration rate
Can millimetre-wave rock-melting beat rotary cost-per-metre in hard hot rock? We measure penetration rate in basalt analogues. High upside, unproven — a bet, named as one.
Supercritical wellbore stability
Materials and completions above 374 °C / 22 MPa are an open problem. We test casing, cement, and tool survival against the conditions, not catalog ratings.
Thermal drawdown over field life
A reservoir cools as you produce. The subsurface twin forecasts the thermal front; we validate it against real bores to size sustainable production.
Direct lithium extraction from brine
Selective recovery of lithium and silica from hot production brine, handed to Resources. Selectivity and uptime at temperature are the measured variables.
Different gradient, same rule. Geothermal is firm, weather-immune power available with today's physics — the heat is proven, only the drilling is hard. It earns its place by capacity factor, not novelty.
Above ~374 °C and ~22 MPa, water becomes a supercritical fluid carrying several times the enthalpy of steam. One supercritical well can deliver the power of many conventional ones — if you can reach and hold those conditions.
It is a research bet at low TRL. Millimetre-wave rock-melting is demonstrated at lab scale; field penetration rates and economics are not proven. We fund it as a bet and report it as one.
Work with the Geothermal team.
Direct to the program team. No newsletter, no funnel.