Senior Thermal Engineer

Company Description

Critical Energy is a trailblazing startup in stealth mode, poised to redefine the world of clean energy.

Our Mission: To build an abundant, low-cost, 100% clean energy future through groundbreaking geothermal innovation.

We’re a team of passionate engineers, designers, and visionaries building cutting-edge solutions to meet the world’s energy needs with 100% clean energy. We are in the early stages of development and building our founding team. This is your chance to get in on the ground floor of something big! If you’re ready to work at a fun, fast-paced, groundbreaking organization that is positioned to revolutionize geothermal energy, apply today!

Role Description

This is a full-time, in-person role for a Principal/Senior Thermal Analyst. The role will be responsible for developing and validating thermal models that are critical to the design and operation of our thermoelectric power plant hardware. This includes:

• Developing 0D thermofluidic system models using first-principles correlations to estimate bulk performance.

• Building and implementing 1D and 2D numerical models from scratch to analyze component and system-level thermal behavior.

• Validating thermal models through experimental testing and hardware correlation.

• Performing trade studies and sensitivity analyses to guide thermal design decisions.

• Working closely with design engineers to provide performance input and influence hardware architecture.

• Translating analytical and simulation results into actionable design recommendations across hardware, fluids, structural, and power engineering domains.

• Supporting the design and analysis of heat exchangers, coolers, and other thermofluidic components.

This role will work side-by-side with mechanical, fluids, and power electronics engineers to develop novel thermal systems from the ground up. The team is focused on rapid prototyping, testing, and iterative improvement of real hardware, with strong alignment between analysis and build.

As with all positions at this stage of the company, this role will evolve significantly over time. The ideal candidate is flexible, mission-driven, and excited to help build a world-class engineering organization from scratch.

Looking for candidates with very strong fundamentals and experience applying them in the real world including hands-on experience with hardware they have developed.

Compensation includes significant equity stake in the startup. Job title and salary is variable based on the applicant and will be chosen to best suit the hire's level. Full health care benefits provided.

Required Qualifications

• Master’s or PhD in Mechanical Engineering, Physics, Aerospace Engineering, Chemical Engineering, or a related discipline with a focus on thermal sciences or thermofluids.

• Demonstrated experience building and validating thermal/fluid models from first principles.

• Strong background in both numerical modeling and experimental testing.

• Hands-on experience working directly with hardware (thermal systems, test rigs, sensors, etc.).

• Solid understanding of fluid mechanics, heat transfer, and thermodynamics.

• Experience with numerical methods for solving heat and mass transport equations (1D/2D modeling).

• Experience translating model results to guide hardware development.

• Excellent analytical and problem-solving skills

• Good communication and team-working skills

• Highly self-motivated

Desired Qualifications

• Experience across multiple industries/applications (aerospace, automotive, power generation, etc.).

• Familiarity with CFD tools such as ANSYS Fluent, STAR-CCM+, COMSOL, Thermal Desktop, or similar.

• Experience designing or analyzing air-cooled and fluid-based heat exchangers.

• Prior work involving thermal systems in power generation or energy applications.

• Familiarity with thermal design for transient and steady-state regimes.

• Understanding of thermal interactions with electrical and mechanical systems.