Principal Magnet Cryogenics Engineer

Thea Energy

• $190K — $215K *
Energy & Utilities
8 - 10 years of experience
Job Overview by Ladders

Qualifications

  • 10-15+ years in cryogenic engineering with a focus on HTS systems.
  • Experience managing large-scale fusion projects over $10M.
  • Expertise in high-current cabled HTS configurations.
  • Full lifecycle experience in superconducting magnet systems from concept to cool-down.
  • Knowledge of cryogenic safety and compliance regulations.

Responsibilities

  • Lead lifecycle from conception to commissioning of HTS cryogenic systems.
  • Design and validate thermal management systems for HTS conductors.
  • Perform dynamic thermal-hydraulic analysis and margin calculations.
  • Develop strategies for quench and fault management during events.
  • Define infrastructure requirements for mega-watt cryogenic plants.
  • Oversee thermal management for high-current HTS joints.
  • Manage vendor contracts for cryogenic systems and infrastructure.
  • Plan and execute magnet test campaigns including cool-down and warm-up procedures.

Benefits

  • Comprehensive health benefits (medical, dental, vision).
  • Employee equity stock options.
  • 20 days paid time off (PTO).
Full Job Description
Position Overview:

We are seeking a Principal Magnet Cryogenics Engineer with over 10-15 years of industry experience to lead the complete program lifecycle-from concept through commissioning-of large-scale cabled High-Temperature Superconducting (HTS) magnet systems for next-generation fusion reactors.

In this role, you will hold end-to-end technical ownership for the cryogenic design, thermal-hydraulic modelling, forced-flow cooling distribution, and cryogenic integration of large-scale CICC (Cable-in-Conduit Conductor) or advanced stacked-tape HTS magnets. You will bridge megawatt scale cryogenic plant engineering with microscopic thermal-hydraulic magnet behaviour, leading multi-disciplinary teams through multi-million-dollar hardware deliverables.

Key Responsibilities:

  • Program Lifecycle Ownership: Lead the complete lifecycle (Conceptual, Preliminary, Detailed Design, Qualification, Fabrication, Assembly, Commissioning, and Decommissioning) for large-scale HTS fusion magnet cryogenic systems.
  • Cryo-Thermal System Architecture: Design, model, and validategaseous helium (gHe), or sub-cooled liquid nitrogen (sLN2) thermal management systems tailored to high-field HTS cabled conductors (stacked HTS conductors).
  • Thermal-Hydraulic Modeling: Perform dynamic thermal-hydraulic analysis, transient load modelling (nuclear heating, AC losses, eddy currents, ramp rates), and margin calculations under operational and fault conditions.
  • Quench & Fault Management: Own the cryogenic response strategy during quench events, including rapid helium expansion, overpressure relief sizing, burst disc integration, and thermo-mechanical stress containment.
  • Large-Scale Infrastructure & Plant Integration: Define requirements for mega-watt class cryogenic plants, cold compressors, heat exchangers, sub-coolers, helium distribution boxes (valve boxes), and low-heat-leak transfer lines.
  • Joints & Current Leads: Oversee cryogenic thermal management for high-current demountable or permanent HTS joints and conduction-cooled hybrid (HTS/LTS) gas-cooled current leads (60+ kA).
  • Vendor & Subcontractor Governance: Manage major sub-contracts for large-scale cryogenic infrastructure, conductor fabrication, pressure vessels, and vacuum insulated systems (cryostats).
  • V&V and Commissioning: Plan and execute full-scale cryogenic and high-current magnet test campaigns, leading cool-down, steady-state operation, quench mitigation, and warm-up procedures.


Required Experience:

  • 10-15+ Years of Direct Experience in cryogenic engineering and thermal-hydraulic design for superconducting magnet systems, with a primary focus on HTS tape/cable architectures (REBCO/BSCCO).
  • Large-Scale Fusion/Physics Program Delivery: Proven track record of ownership over large-scale (> $10M+) magnet work packages within fusion energy programs (e.g., W7x, ITER, JT60SA, KSTAR, DEMO) or major scientific facilities (e.g., CERN, FERMILAB).
  • Cabled HTS Architecture: Demonstrated expertise in high-current (tens of kA) cabled HTS configurations (e.g., Cable-in-Conduit Conductors, stacked tape conductors) and forced-flow cooling strategies.
  • Full Lifecycle Track Record: Experience taking at least one major superconducting magnet or cryogenic system from initial concept through initial cool-down and operational validation.
  • Regulatory & Code Compliance: Deep familiarity with pressure vessel standards applied to cryogenic temperatures (ASME BPVC Section VIII, EN 13445, B31.3) and cryogenic safety standards (ISO 21010/CGA).

Technical Knowledge
  • HTS Material Physics: Solid understanding of critical surfaces for REBCO coated conductors, strain sensitivity, thermal margin assessment, and current sharing regimes.
  • Cryogenic Fluids & Thermophysical Properties: Mastery of low-temperature fluid dynamics (gHe, sLN2) using database tools.
  • Transient Thermal Analysis: Deep domain knowledge of AC losses (coupling, hysteresis, flux creep) nuclear volumetric heating, heat-leak budgets, and conduction/radiation thermal shielding (MLI design).
  • Instrumentation & Controls: Extensive knowledge of low-temperature thermometry (Cernox, TVO, optical fibers/FBG), cryogenic flow meters, pressure transducers, and cryogenic valve telemetry.

Skills & Competencies
  • Computational Tools: Proficiency in finite element analysis (FEA) and thermal-hydraulic system modeling tools (e.g., COMSOL Multiphysics, ANSYS Thermal/CFD, MATLAB/Simulink).
  • System Engineering & Requirements Flowdown: Capability to write clear system requirement documents (SRDs), interface control documents (ICDs), and lead major design reviews (CoDR, PDR, CDR).
  • Leadership & Team Mentorship: Demonstrated ability to lead cross-functional engineering teams (structural, electrical, vacuum, systems) and mentor junior magnet/cryogenic engineers.
  • Strategic Risk Mitigation: Mastery of FMEA, applied to cryogenic system failures, vacuum loss (loss of vacuum/L VAC), and runaway quench scenarios.


Company Benefits:

  • Comprehensive health benefits (e.g. medical/dental/vision)
  • Employee equity stock options
  • 20 days PTO


$190,000 - $215,000 a year

It's not necessary to meet all of the skillsets outlined above. Please feel free to send us a note and tell us why you would still be a great fit for this role or Thea Energy.

Similar Jobs

More Jobs at Thea Energy

More Energy & Utilities Jobs

Find similar Principal Magnet Cryogenics Engineer jobs: