Senior Mechanical Design Engineer - Electromechanical

Company Overview Mainspring Energy is revolutionizing power generation with the world’s most flexible and adaptable local power generation technology, 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 reaction with near‑zero NOx emissions. Backed by top‑tier investors including Khosla Ventures, Bill Gates, American Electric Power, Lightrock, and General Catalyst, 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. Job Overview Mainspring is seeking Staff Mechanical Design Engineers with a focus on designing electrical enclosures and cables while improving functionality and system‑level performance. In this role, you will lead projects from setting requirements, designing, conducting cross‑functional reviews, coordinating testing and release to ensure that key electrical subsystems meet challenging technical requirements with a potential for direct reports. Ideal candidates will have a strong combination of technical expertise and the drive to solve complex problems in a collaborative environment. Core Responsibilities Involved in brainstorming and technical review sessions to develop innovative solutions that enhance the performance and cost‑efficiency of the Linear Generator and electrical subsystems Ownership of design, optimization, and execution of electrical hardware, balancing cost reduction, safety improvements, and system‑level reliability Collaborate with reliability and test teams to validate systems and components, ensuring fast iteration cycles and incorporating feedback to drive the next‑generation deployment of the Linear Generator Collaborate cross‑functionally with electrical engineering, manufacturing engineering, NPI, and external suppliers to deploy new designs into production, ensuring all systems meet the necessary performance and manufacturability requirements Development of electrical hardware, including requirements development, prototyping, testing, iteration, and tooling, ensuring project milestones are met and resources are allocated effectively Qualifications Degree: BS or MS in Mechanical Engineering or a similar engineering field from an accredited institution. Experience and degree will determine the level, with the following minimum requirements: Senior: BS + 8 years or MS + 6 years Proven experience taking ownership of electrical enclosure and/or cable design, from initial design to launch Strong expertise in sheet metal design for medium‑volume production, electrical component specification, mechanical design for electrical systems, and design‑for‑manufacturability challenges A solid understanding of electrical engineering principles and thermal modeling, and the ability to integrate them effectively into larger system designs Extensive experience in SolidWorks and PDM (or a similar CAD version control system). Experience with CFD, FEA, and programs like SolidWorks Flow Simulation or Ansys is a plus Demonstrated ability to manage complex technical decisions, influence the direction of designs, and coordinate with teams to achieve successful outcomes Passion for creating innovative and cost‑effective solutions to enable the large‑scale deployment of zero‑carbon energy technologies $133,000 - $156,000 a year This position is onsite at our Menlo Park HQ. The salary will be adjusted to reflect local market conditions based on employee location as well as the experience of the employee. Along with the base salary, Mainspring offers pre‑IPO stock options and benefits. 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. 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. #J-18808-Ljbffr