Circularity Fuels

Details

Position: Mechanical Engineering Intern 
(Pilot Hardware and Fluid Systems)
Location: Redwood City, CA
Innovation Area: Materials and Chemicals; Energy, Food, and Water Nexus; Generation and Conversion
Position Type: TomKat Center-supported
Compensation: $8,500
Internship Term: 8 weeks

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Circularity Fuels is developing a pathway to convert biogas-derived methane into low-carbon fuels, including sustainable aviation fuel (SAF). Our work spans lab experimentation, reactor development, and scale-up planning for commercial deployment.

About the Role

We are seeking a highly independent Mechanical Engineering intern to help design, build, and test mechanical hardware and fluid systems supporting our pilot and commercial scale-up roadmap. The work is hands-on and will include rapid iteration from design to fabrication to testing.

Key Responsibilities

  • Design, develop, and test novel mechanical hardware and fluid systems.
  • Collaborate with cross-functional teammates to integrate controls, electronics, and software components.
  • Run and interpret hardware simulations in SolidWorks Simulation, Ansys, or similar tools, then validate with bench testing.
  • Create mechanical drawings to industry standards and design parts for manufacturability and integration into larger assemblies.
  • Assemble and operate fluid systems safely, including fittings, valves, pumps, and pressure-rated components.
  • Document designs, test plans, procedures, and results to enable repeatability and knowledge transfer.

Required Expertise

  • Currently pursuing a bachelor's degree in Mechanical Engineering (Stanford undergraduate preferred for TomKat), or a closely related discipline.
  • Coursework or project experience in thermofluids, heat transfer, or related topics.
  • Strong CAD proficiency (SolidWorks or similar), with the ability to produce drawings suitable for fabrication.
  • Demonstrated hands-on capability building and troubleshooting mechanical systems.
  • Clear written and verbal communication skills and comfort working across disciplines.
  • Commitment to safe work practices and attention to detail in a laboratory and hardware environment.
  • Ability to manage multiple workstreams, prioritize, and execute with limited oversight.

Preferred Skills

  • CFD simulation experience and experimental design experience.
  • Prior internship or project experience designing, manufacturing, and testing mechanical hardware.
  • Experience with pressure systems, leak testing, and standard lab or shop tooling.

Who Should Apply

This role is a strong fit for a builder who enjoys translating engineering fundamentals into working hardware, learning quickly through iteration, and taking ownership of deliverables. Students who are curious about scaling climate and energy hardware from early prototypes to pilot systems will do well.

Learning Opportunities

  • Hands-on experience designing and operating fluid systems and pilot hardware.
  • Exposure to the realities of scale-up, safety, and manufacturability in energy hardware.
  • Mentorship from engineers working across R&D and project development.

Application Materials

  • Resume
  • Short note (2 to 4 paragraphs) describing your most relevant hands-on project and why you want this internship
  • Unofficial transcript (optional)

TomKat Program Notes

This position will be filled through the TomKat Center Energy Internship Program. The TomKat Center pays the $8,500 stipend directly to the student. Circularity Fuels provides supervision, mentorship, and an on-site work environment.