Mechanical Engineer; Balance of Plant​/Plant Systems) Remote

Mechanical Engineer (Balance of Plant / Plant Systems)

Remote, USA

Applied Atomics delivers firm, clean electricity with proven technology. We design, build, and operate nuclear plants directly alongside the facilities they power. With n o reactor science or new fuel to invent , we have n o reason to stall. We are the first fully integrated nuclear power provider built to deploy now. Founded by a team of engineers and operators who built the launch sites, test complexes, and factories behind SpaceX , designed and commercialized nuclear reactors, and ran billion-dollar asset portfolios , the team is now focused on clean power deployment.

Applied Atomics is b acked by Alpaca VC, Transition, and Morpheus Ventures.

About the role:

Applied Atomics is seeking a Mechanical Engineer to support the design, development, and build-out of the major thermal-fluid systems for our first-of-a-kind (FOAK) nuclear power plant. You’ll work alongside senior engineers to develop systems such as the main steam system, feedwater system, condensate system, air-cooled condenser (ACC), heat exchangers, pumps, valves, piping, and auxiliary thermal-mechanical equipment.

This is a high-impact role for an engineer who wants to learn fast, contribute to real hardware, and have ownership of major plant systems. You’ll perform engineering analysis, system modeling, CAD design, vendor coordination, testing support, and system integration. If you are a strong mechanical engineer who enjoys complex thermal-fluid systems, hands-on hardware, and startup pace, you’ll thrive here.

Why we need you

We are transitioning nuclear energy from a theoretical science into a practical reality, and that requires practical problem-solvers. We need engineers who are eager to take direct responsibility for their work and see it through to completion. Your role will be critical in transforming complex designs into safe, reliable, and operational power plants that will operate for decades to come.

What you will do

Key Responsibilities

• Work on the design and development ofbalance-of-plant (BOP) systems, including but not limitedto:main steam system & piping, feedwater system, condensate system, air-cooled condenser systems, heat exchangers and auxiliary systems, turbine-side thermal cycle equipment & interfaces.
• Support creation of mechanical design concepts, equipment layouts, and piping configurations.
• Ensure designs comply with applicable design criteria, requirements, and system interfaces.
• Perform thermal, structural, and fluid analyses using hand calcs and engineering tools.
• Support development, review, and validation of system simulation and analytical models (e.g., thermal cycles, pressure drops, transient behavior, etc.).
• Create and update CAD models, drawings, and system diagrams(NX, Solid Works, Creo, etc.).
• Proficient with fluid system PIDs.
• Develop and maintain design documentation, including descriptions, technical notes, calculations, and engineering change packages.
• Support preparation and presentation ofPDRs, CDRs, and internal design gates.
• Support vendor outreach for pumps, valves, heat exchangers, piping, instrumentation, and packaged equipment.
• Support manufacturing, assembly, and installation of BOP systems.
• Support development of test plans, integration procedures, and commissioning documentation.
• Participate in hardware bring-up, field testing, and system-level troubleshooting as needed
• Interpret and implement industry codes and standards (ASME,API, NRC, etc.).
• Collaborate with interfacing system owners.
• Support documentation for regulatory submissions (e.g., NRC).
• Define and manage Bills of Materials (BOMs), component specifications, and configuration control.
• Develop…