Technologies
Technology Overview —
The Cold-Sink Advantage
Conventional combined-cycle plants reject heat to ambient air or cooling water — a sink temperature around 25 to 40°C. Our system rejects heat into the LNG itself as it vaporizes from −162°C up to ambient. That cold sink is more than 200°C colder than the alternative, dramatically expanding the Carnot envelope available to the bottoming cycle.
The result: a 3.3 MW gas turbine yields ~6.5 MW of net combined output — nearly doubling the work extracted from the same fuel — without adding a fuel-burning stage.
The Three-Stream Architecture
- Hot stream: Gas turbine exhaust at 505°C drives the HRSG that vaporizes ethylene
- Cold stream: LNG vaporizing from −162°C condenses ethylene at −130°C / 0.17 bar
- Working stream: Ethylene R1150 expands across a 2-stage turbine at 118:1 pressure ratio
Performance Comparison
| System | Efficiency | Portable |
| Diesel genset | 38–42% | Yes |
| Reciprocating gas engine (Caterpillar, Wärtsilä) | 42–50% | Yes |
| Simple-cycle gas turbine | 28–38% | Yes |
| Conventional combined-cycle plant | 55–62% | No (fixed) |
| NexGen CryoDrive 5 | 58.2% | Yes (2 containers) |
The Cryo-ORC Cycle Explained
An Organic Rankine Cycle is a closed-loop heat engine that uses an organic working fluid instead of water. The cycle has four stages: pump, evaporate, expand, condense. CryoDrive's innovation is in the condense stage — using LNG cold instead of ambient cooling.
Working Fluid: Ethylene R1150
- Critical point: 9.2°C / 50.4 bar — supercritical heat absorption in HRSG eliminates pinch point
- Operating range: −130°C (condenser) to 150°C (turbine inlet); 0.17 to 20 bar
- Classification: ASHRAE A3 (flammable, low toxicity); GWP < 1
- Why ethylene: Selected from a six-fluid evaluation matrix as optimal for the LNG cold sink temperature; dry fluid behavior eliminates wet expansion risk
Cycle State Points (CD5-3200 Reference
The full system has 16+ engineered state points covering all flows, temperatures, pressures, and phases. Key conditions:
| Point | Description | T (°C) | P (bar) |
| SP-1 | Ethylene at HRSG inlet (post-recuperator) | ~80 | 20 |
| SP-2 | Ethylene at turbine inlet (HRSG outlet) | 500 | 20 |
| SP-3 | Ethylene at turbine outlet (post-expansion) | ~150 | 0.17 |
| SP-4 | Ethylene at recuperator hot outlet | ~−25 | 0.17 |
| SP-5 | Ethylene condensed | −130 | 0.17 |
| SP-6 | LNG fuel inlet (cold sink) | −162 | — |
Full state-point detail and HYSYS verification documentation available under NDA for technical evaluation.
Core Components
Gas Turbine — Honeywell SPG 54
- 3.3 MWe aero-derivative; 14,400 RPM
- Military heritage; 40,000-hour track record
- Dual-fuel capable (LNG, NG, propane/LPG, diesel backup)
- Sourced via Signal Power Group (Brookshire, TX) — sole civilian licensee
Permanent-Magnet Generator — Hitachi Custom
- 3.3 MWe synchronous IPM; 6,900V, 480 Hz
- Cryogenic cooling option using LNG cold
- ~950 kg total; 4-pole interior PM rotor with 17,600 RPM overspeed rating
- 17-4 stainless shaft (UNS S17400); Nomex/polyamidimide insulation
- MTBF 120,000 hr; overhaul 40,000 hr; unit replacement in 10 hours
Heat Exchangers
- HRSG: Finned-tube, double-wall (ethylene auto-ignition safety); 7,880 kW; 505°C → 0°C
- Recuperator (IHX): Brazed aluminium plate-fin; 7,144 kW; ε = 60%; vendors: Chart Industries, Linde
- ORC condenser: Shell-and-tube or BAHX; 4,747 kW; ethylene at −130°C / LNG at −162°C
- GT inlet cooler: Compact fin-tube; 440 kW; LNG cold; 40°C → 5°C
ORC Turbine & Pump
- 2-stage axial or radial expander; 118:1 PR; 3,384 kW gross; 85% isentropic target
- Magnetic-drive centrifugal pump (hermetic — no shaft seal at 0.17 bar suction); 236 kW
- Candidate vendors: Atlas Copco, Turboden, GE Dresser-Rand
Power Conversion & Controls
- Isolation transformer 6.25 MVA; AC/DC converters 2× 2.6 MWe → 500–800 VDC
- Engine control: Woodward Flex; Alternator monitoring: Woodward 3500 XT
- ORC control: Siemens S7 PLC with ethylene inventory management
- Safety systems: SIL 2 rated; ATEX-certified instrumentation throughout ORC zone
IP Portfolio
NexGen has filed nine patent applications covering the core CryoDrive architecture and railroad propulsion concepts. Five US provisionals are scheduled for conversion to utility filings, with an additional seven applications planned during the 2026–2027 prosecution cycle.
Patent Application Portfolio
- 8. AI ground traffic control software for distributed-propulsion freight rail
- 9. Hybrid modular freight train design (1/8 scale model + dynamic testing)
- 10. End-of-train control car (55 ft depressed platform chassis)
- 11. Modular freight car (55 ft depressed platform with steeraxle)
- 12. Railroad car steeraxle with independent traction motors
- 13. LNG power generator-set prototype for qualification testing
- 14. Distributed power delivery system (1/8 scale)
- 15. Factory-built containerized 5–10 MWe stationary power systems
- 16. Novel cryogenic cooling system for permanent-magnet motors and generators
Founder Patent Heritage
Dennis W. Chalmers is named as lead inventor on every USPTO LNG cryogenic submerged motor pump and turbo-generator patent applied for or granted since 2004. He holds two World Patents covering TC 34.2 LNG cryopumps and electric feed-throughs. This 20-year body of work establishes the technical credibility that supports the current patent prosecution strategy.
Technology Roadmap
2026 — Validation
- HYSYS thermodynamic simulation completed and independently verified
- First prototype build at Kingman, AZ — GT + cryo-ORC integrated test
- 500-hour endurance test with full telemetry instrumentation
2027 — First Commercial Deployments
- 3 pilot units delivered to Permian Basin operators under cost-plus pricing with performance guarantees
- FAT acceptance test protocol formalized; ISO 9001 framework in place
- Hitachi generator series-production qualification
2028–2030 — Scale & Adjacencies
- CD5-5000 and CD5-8000 production lines stood up
- Data center behind-the-meter deployments at hyperscale customers
- RailPower 1/8-scale dynamic testing complete; FRA approval pathway initiated
2030+ — Carbon Capture Integration
- Oxy-fuel Brayton cycle topping stage for near-zero-emission LNG power
- CO₂ sequestration integration for Permian Basin EOR applications
- IP licensing to industrial gas companies for global LNG terminal integration