Internship - Mechanical Engineer (Fluid Systems, Mechanisms, or Structures)

Radiant is an El-Segundo, CA-based clean energy startup building a nuclear microreactor. A climate-friendly alternative to diesel generators, Radiant's Kaleidos 1MW microreactor will be the world's first portable, zero-emissions power source that works anywhere. We plan to test our development reactor by 2026 and if successful, it will be the first new commercial reactor design to achieve a fueled test in over 50 years. Radiant's goal is to bring one of the world's first factory-constructed microreactors to market. Our microreactor can bring power to remote parts of the world and provide backup power for life-saving applications in hospitals or disaster-relief scenarios.

Internship - Mechanical Engineer (Fluid Systems, Mechanisms, or Structures)

Radiant is seeking a highly motivated Mechanical Engineering Intern for Fall 2025. Under the KDU Engineering team, you will be responsible for a project tailored towards the finalization of the design, assembly and testing of the Kaleidos Development Unit – the United States' first new fueled reactor design in over 50 years. You will be tasked with this project based on your skillset (fluid systems, mechanisms, or structures) and our organization's priority. You'll learn from a direct mentor, cross-functional teammates, and have a tangible impact on the readiness of KDU for fueled operations next year.

Responsibilities and Duties:

- Own all aspects of a project within given discipline.

- Deliver project on time and with minimal supervision to accelerate KDU development.

- Present a final project review at the end of internship to engineers and leadership.

Required Skills and Qualifications:

- Strong connection to engineering first principles expected from a third-year engineering student (thermodynamics, fluid mechanics, statics, dynamics, strength of materials).

- Currently pursuing BS in mechanical engineering, aerospace engineering, or related discipline.

- Hands on project examples outside of the classroom such as extracurricular projects, clubs, research, lab work or personal projects.

Desired Skills and Qualifications:

- Currently pursuing MS in mechanical engineering, aerospace engineering, or related discipline.

- A high level of independence in solving challenging engineering tasks is preferred.

- Ability to seek out resources and proactively ask questions to finish projects through completion effectively, accurately, and timely.

- Ability to work in a fast-paced startup environment with a proactive and collaborative attitude.

- Genuinely excited for our mission to rapidly deploy nuclear microreactors to remote locations requiring abundant, clean energy.

- Knowledge of reactor physics will provide useful context but is not necessary.

- Prior internship experience helpful but not required.

Additional Requirements:

- This internship will require working onsite at our El Segundo HQ.

- You may be asked to work extended hours or weekends occasionally to support project goals.

Employee Benefits for Eligible Employees:

- Stock: Substantial incentive stock plan for all full time, salaried employees.

- Medical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans.

- One Medical: Sponsored memberships for employees and their dependents.

- Vision: 100% top tier plan coverage + 50% for dependents.

- Dental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.

- Voluntary Life, Accident, Hospital, Critical Illness, Commuter and FSA are offered as employee contributed benefits.

- Free snacks and drinks onsite.

- Flexible PTO policy.

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability status, genetic information, protected veteran status, or any other characteristic protected by law.

Unfortunately, we are unable to provide visa sponsorship at this time. This position involves access to technology that is subject to U.S. export controls. Any job offer made will be contingent upon the applicant's capacity to serve in compliance with U.S. export controls.