Senior Staff Mechanical Engineer

Mainspringenergy; Edison (CA); On-site; USD 140,000 - 190,000; Full time

Job summary

Mainspring Energy seeks a Senior Staff Mechanical Engineer to shape technical direction across multiple teams within the Linear Generator platform. You will guide system-level design decisions, resolve cross-functional tradeoffs, and establish validation strategies and data-driven guidance for high-consequence decisions.

Ideal candidates demonstrate advanced technical ownership, operate with autonomy, align stakeholders, and improve decision quality across projects while balancing performance,

Qualifications

• This role requires advanced technical ownership across mechanical systems and programs.
• Demonstrated ability to lead cross-functional design decisions and tradeoffs.
• Experience developing hardware for energy systems and validated design curves.

Responsibilities

• Lead technical direction for broad mechanical projects with high ambiguity and program impact.
• Guide architecture and subsystem-level design decisions across teams.
• Frame complex problems, identify tradeoffs, and align stakeholders on paths forward.
• Establish validation, test, and data strategies for major technical decisions.

Skills

Technical leadership

Cross-functional

System-level design

Risk assessment

Data-driven decisions

Stakeholder alignment

Education

BS/MS/PhD in Mechanical Engineering

Tools

FMEA

System modeling

Finite element analysis

Job description

About Mainspring

Mainspring Energy manufactures and delivers fuel-flexible, low-emissions local power solutions that rapidly add new capacity and deliver reliable, affordable, and sustainable electric power. The company began commercial shipments of its Mainspring Linear Generators in 2020 and today has hundreds of megawatts in advanced development and field operations for leading Fortune 500 companies, data centers, and utilities. Mainspring also partners with global energy leaders including AEP, NextEra Energy Resources, Schneider Electric, and more.

The core values that ground our work, guide our decisions, and connect us together:

• Pragmatic Optimism
• Excellence without Ego
• Proactive Collaboration

About the Role

Mainspring is seeking a Senior Staff Mechanical Engineer to shape technical direction across multiple teams, systems, or major program areas within our Linear Generator platform. In this role, you will guide system-level design decisions, resolve complex cross-functional tradeoffs, identify risks that may not be visible within individual projects, and create technical leverage through architecture, standards, validation strategy, and high-quality decision-making.

This role is intended for engineers who have already demonstrated advanced technical ownership within a major subsystem, team, or technical area and are now ready to influence outcomes across a broader part of the organization. A strong candidate should be able to operate with high autonomy, frame ambiguous system-level problems, align stakeholders, improve technical decision quality across projects, and help teams avoid rework caused by weak assumptions, incomplete validation, or missed integration risks.

Candidates who primarily provide technical leadership within one team, subsystem, or technical area may be better aligned to a Staff Mechanical Engineer role, while candidates who serve as a company-level technical authority in a critical domain may be better aligned to a Principal Mechanical Engineer role.

• Lead technical direction for a broad system, platform area, discipline, or group of related mechanical projects with high ambiguity, system-level tradeoffs, and major program impact.
• Guide architecture, system, subsystem, or platform-level design decisions that affect multiple projects or teams, balancing technical performance, reliability, cost, manufacturability, serviceability, scalability, and business priorities.
• Frame complex cross-functional problems at the right level, identify critical tradeoffs, and drive alignment on practical technical paths forward.
• Establish analysis, validation, test, and data strategies for major technical decisions where the available evidence may be incomplete, imperfect, or spread across models, experiments, field data, and production learning.
• Identify system-level risks, recurring failure modes, integration gaps, and organizational blind spots that may not be visible within individual projects.
• Create technical leverage across teams through design reviews, risk reviews, architecture discussions, technical strategy, standards, methods, troubleshooting, and guidance on high-consequence decisions.

• BS, MS, or PhD in Mechanical Engineering or a similar engineering field, with demonstrated success providing technical leadership across complex mechanical systems, subsystems, or major program areas.
• Repeated experience developing, validating, releasing, and improving complex hardware across multiple design cycles, project types, failure modes, and implementation environments.
• Strong system-level mechanical judgment, including the ability to balance performance, reliability, cost, manufacturability, serviceability, scalability, safety, schedule, integration, and business priorities.
• Demonstrated ability to resolve ambiguous, cross-functional technical problems where ownership, requirements, evidence, or tradeoffs are not initially clear.
• Proven ability to use analysis, testing, data, field learning, production learning, and engineering judgment to make or guide high-consequence technical decisions.
• Strong communication and influence skills, including the ability to align stakeholders across teams and levels of the organization around technical strategy, risks, tradeoffs, and recommended paths forward.

• Experience serving as the technical lead or subject matter expert for a broad system, product area, platform, or discipline.
• Experience developing hardware for energy systems, engines, generators, compressors, pumps, thermal systems, fluid systems, structures, high-cycle fatigue environments, precision alignment systems, electromechanical systems, or industrial equipment.
• Experience creating design standards, architecture principles, validation methods, risk frameworks, review practices, troubleshooting methods, or other reusable approaches that improve engineering execution across teams.
• Experience with reliability strategy, accelerated life testing, failure analysis, structured root cause analysis, design of experiments, risk-based validation planning, or system-level trade studies.
• Experience influencing major technical decisions across engineering, manufacturing, quality, supply chain, suppliers, service, product, or leadership stakeholders.
• Experience helping teams sequence work, reduce uncertainty, avoid rework, and focus on the highest-leverage technical problems.

Does your experience not meet all of our posted requirements? Studies have shown that some people are less likely to apply to positions unless they meet every listed requirement. At Mainspring, we are committed to building a diverse, inclusive, flexible, and collaborative environment, so if you want to help us transition the world to clean and affordable electricity, and don’t meet all posted requirements for a particular role, we’d still love to hear from you. Mainspring can sometimes be flexible enough to shift responsibilities for the right person, or otherwise identify open or upcoming roles that may better fit your professional background.

In more traditional words, Mainspring Energy, Inc is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status and will not be discriminated against on the basis of disability.

This compensation and benefits information is based on Mainspring Energy's estimate as of the date of publication and may be modified in the future. We generally do not negotiate on salary once we have made an offer. The level of pay within the range will depend on a variety of job-related factors that may include location, relevant prior experience and/or education, or particular skills and expertise. New hires joining the company tend to be paid within the starting base pay range noted above, with opportunities to increase pay over time based on development of additional skills, competencies, and company-specific knowledge.