Staff Mechanical Engineer - Exhaust System

Company Overview

Mainspring Energy is revolutionizing power generation with the world’s most flexible and adaptable onsite power generator, the Mainspring Linear Generator. Commercial, industrial, and utility leaders are choosing Mainspring over traditional options like engines, turbines, and fuel cells to quickly and reliably deliver local power for EV charging, commercial facilities, data centers, and grid-scale operations. The Mainspring Linear Generator is fuel flexible, ramps up and down to meet demand, and utilizes a flameless technology with near-zero NOx emissions.

Backed by top-tier investors such as Khosla Ventures, Bill Gates, American Electric Power, and Lightrock, Mainspring designs, manufactures and delivers its products to customers across the U.S. today, and we’re quickly scaling for international expansion.

Inspired by our vision of the affordable, reliable, net-zero carbon grid, Mainspring is rapidly expanding within the $816B global electricity equipment market, and we’re hiring the best talent to meet growing customer demand around the globe. We welcome a broad range of backgrounds, experiences, and talents to bring fresh perspectives and ongoing innovation to our customers.

We are looking to build relationships with people who share our values:

Pragmatic Optimism. Building a new category of world-class power generation requires the optimism of ambition and creativity, balanced with practicality to solve problems efficiently. The challenges that arise are opportunities for growth.

Excellence without Ego. We bring expertise and commitment to creating the best customer experience, from sales to deployment and service, just as we apply deep technical rigor to building and delivering world-class products. We strive for excellence and behave as leaders with the humility to acknowledge our challenges, both collectively and as individual contributors.

Proactive Collaboration. The integration and cross-disciplinary nature of Mainspring’s business requires intentionally seeking out others who bring different skills, perspectives, and priorities. Our culture of inclusion and respect extends beyond our team to interactions with our partners and customers.

More information can be found at www.mainspringenergy.com

Job Overview

Mainspring Energy is seeking a highly talented Staff Mechanical Engineer to take a leading role in the design and development of the exhaust system for our innovative Linear Generator technology. This critical system manages high temperatures and vibration while ensuring emissions compliance, acoustic attenuation, and long-term durability. This challenging role requires strong technical leadership, creativity, deep expertise, and broad skills to drive significant advancements in this crucial area of our clean energy solution.

• Own and lead the full product development lifecycle of complex exhaust subsystems, including architectural decisions, conceptualization, detailed design, advanced 3D CAD modeling (Solidworks), sophisticated engineering analysis (FEA/CFD tools like ANSYS for coupled thermal-structural-flow analysis), rigorous testing strategies, in-depth root cause investigation, and comprehensive documentation
• Drive innovative solutions for challenging exhaust system requirements, including advanced material selection for extreme temperatures, robust design strategies for severe vibration and long-term durability, optimization of emissions control performance, and innovative acoustic attenuation techniques (e.g., muffler design)
• Architect and guide collaboration with cross-functional teams (Electrical Engineering, Controls, Manufacturing, Suppliers) to ensure seamless subsystem integration, optimize performance, and lead new product introduction efforts (DFM/DFA strategy, work instructions, tooling/fixtures design)
• Develop, plan, and execute rigorous verification and validation testing campaigns to ensure designs meet and exceed demanding requirements (functional, durability, thermal, vibration, acoustic, safety, reliability)
• Provide technical guidance and mentorship to junior engineers and technicians, and actively contribute to the continuous improvement and definition of engineering processes, tools, standards, and best practices related to exhaust system design and analysis
• Stay current on advancements in mechanical engineering relevant to exhaust systems, power generation, acoustics, and emissions control, proactively identifying and championing opportunities to reduce cost, improve performance, and increase reliability
• Uphold and further Mainspring's mission to create clean, affordable, and reliable power generation that accelerates the world's transition to a sustainable energy future

• Bachelor's or Master's degree in Mechanical Engineering or similar field
• 8+ years as a professional mechanical design engineer, demonstrating increasing levels of responsibility and technical leadership
• Delivered products as a technical lead through 3+ full design lifecycles from concept to manufacturing support, preferably involving industrial equipment, power generation, engine systems, or similar demanding applications
• Self-starter with a proven ability to architect and deliver complex, functional designs in a rapid development environment, with a strong track record of innovation and continuous improvement

• Deep expertise designing components or systems operating in high-temperature and high-vibration environments, with a strong understanding of relevant failure modes
• Mastery of engineering fundamentals in thermo-fluid system design and structural mechanics. Extensive experience with stress analysis, and vibration analysis (FEA) is required
• Proven ability to design for durability, fatigue life, and reliability in harsh operating conditions, including thermal fatigue considerations
• Demonstrated expertise in acoustic analysis and muffler design, or deep experience architecting and integrating emissions control systems (e.g., catalysts, SCR), is highly desirable
• High proficiency in 3D CAD modeling (Solidworks preferred), expert-level engineering drawing creation (GD&T), and experience implementing or managing PDM or similar CAD version control systems
• Advanced knowledge of mechanical design principles, materials selection (esp. high-temp alloys, ceramics), manufacturing processes (sheet metal, welding, casting, joining techniques), and proven ability to anticipate and resolve complex DFM issues
• Strong hands-on mechanical prototyping, assembly, and testing skills, including defining test requirements and interpreting complex data from various instrumentation
• Expertise with engineering analysis tools (FEA), including results interpretation, model validation, and driving design decisions based on simulation

• Excellent problem-solving, creative thinking, communication, and collaboration skills for effective cross-functional teamwork and technical leadership
• Ability to work independently, manage complex projects and priorities in a fast-paced environment, and demonstrate strong leadership and mentoring abilities
• Passion for clean energy and commitment to creating a more sustainable world

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.