Principal Engineer, Safety Methods

About TerraPower

TerraPower is a nuclear technology company based in Bellevue, Washington. The company works to raise living standards globally through more affordable, secure, and environmentally friendly nuclear energy and innovations in medical isotopes. Founded in 2006 by Bill Gates and a group of visionaries, TerraPower’s mission is to be a world leader in new nuclear technologies while developing innovators and future leaders in the nuclear field. Its activities span nuclear energy, hybrid energy, and medical applications, delivering safety, economic, and health benefits.

Responsibilities

• Support verification, validation, and uncertainty quantification (V&V) activities for plant‑scale thermal‑hydraulic analysis tools.
• Develop and execute code assessment plans, including validation matrices, test selection, and quantitative comparison methodologies.
• Perform scaling analysis to evaluate the applicability of test data to reference system conditions, assessing similarity criteria and scaling distortion.
• Interpret and apply experimental data from separate‑effects and integral test facilities to support model validation and close technical gaps.
• Define validation needs, develop test requirements, and collaborate with test engineering teams to align model gaps with experimental programs.
• Document V&V methodologies, model assumptions, validation results, and uncertainty analyses for internal design processes and regulatory submittals.
• Collaborate with multidisciplinary teams to support plant design, safety analysis, and licensing workflows.
• Apply and improve TerraPower’s SQA and NQA‑1 modeling quality practices, ensuring traceability and configuration control of analysis inputs, models, and results.
• Mentor junior engineers in system modeling, validation methodologies, and best practices in code assessment.

Qualifications and Skills

• Degree in Mechanical, Nuclear, Chemical Engineering, or a related field.
• 8 + years of experience in system‑level thermal‑hydraulic analysis and code assessment for nuclear or complex energy systems.
• Demonstrated experience in code assessment, model‑to‑test comparison, validation metric development, and uncertainty quantification.
• Hands‑on experience with experimental thermal‑hydraulic data, including data analysis, uncertainty evaluation, and comparison against system‑level predictions.
• Proficiency with system analysis tools (e.g., RELAP5‑3D, TRACE, SAS, or equivalent) for plant‑scale transient and steady‑state evaluations.
• Strong foundation in thermal‑fluid and reactor system behavior relevant to advanced reactor designs.
• Experience performing scaling analysis, applying similarity criteria, and qualifying scaling distortion impacts.
• Experience developing validation strategies, defining data needs, and coordinating with experimental programs.
• Familiarity with SQA and NQA‑1 quality‑assurance practices for modeling workflows (highly preferred).
• Strong analytical thinking, clear technical communication, and ability to manage multiple validation tasks in parallel.

Physical Requirements

• Sitting for extended periods; bending/stooping; grasping/gripping; fine motor control (hands).
• Minimal physical exertion with ability to safely lift up to 25 lb.
• Prolonged repetitive work; visual and audio‑focused tasks.
• Work environment includes stairs, typing/keyboard use, standard office setting (>8 hours/day).
• Travel required: 0‑10 %.

Compensation

Salary Range: $140,021 – $181,845 (Washington State). Full‑time position.

Benefits

• Competitive compensation with eligibility for discretionary short‑term incentive payments.
• Comprehensive medical, vision, dental, and wellness benefits.
• Life and disability insurance.
• Gender affirmation benefits.
• Parental leave.
• 401(k) plan.
• Generous paid time off: 21 days of annually accrued PTO plus 10 paid holidays.
• Relocation assistance.
• Professional and educational support opportunities.