Senior Mechanical Design Engineer

Company Overview Amperesand is reinventing how the world powers its most critical systems. We are facing a once-in-a-generation opportunity for infrastructure disruption. Electricity demand is skyrocketing, driven by AI factories, electric vehicles, and modern industrial growth. Energy supply is shifting to incorporate a more diverse mix of resources – including solar, gas, and batteries – at a massive scale. And yet the power infrastructure behind our latest mega-projects hasn’t meaningfully changed in nearly 100 years. Supply chains for today’s infrastructure equipment can’t match the pace and sophistication of critical energy projects. Amperesand is building hardware and software that rewrites this broken power infrastructure playbook to support a new era of energy abundance. We’ve built a new class of intelligent, software-defined power infrastructure products leveraging a decade of advanced medium voltage Solid State Transformer research that’s now ready for commercial deployment. Our products and solutions go far beyond the capabilities of traditional electrical equipment. We make power systems that are faster to deploy, dramatically smaller and more efficient, and capable of supporting modern, dynamic energy needs for tomorrow’s most demanding energy consumers. Scalable in-house advanced manufacturing capability is our foundation for meeting timeline and quality expectation to serve infrastructure customers around the world. Amperesand is led by breakthrough energy hardware development veterans and funded by top tier investors who share our vision of building a category-defining energy technology company. With hubs in San Francisco, Reno, and Singapore, our global team is laser focused on building foundational technology to solve the most pressing problems in power infrastructure at scale. Join us in building the power foundation of the future! Role Summary: We are seeking a skilled Senior Mechanical Design Engineer to join our team and contribute to the development of power electronics products. The primary function of this position is to design custom machinery and support the entire project cycle from concept development through installation, commissioning, and handover to the operations team. You will work closely with cross-functional teams, including product design, Controls, manufacturing, and test engineers, to ensure efficient performance and reliability in high-power density environments. Responsibilities: Utilize CAD software CAD software (3D EXPERIENCE (3DX), CATIA, NX, SolidWorks, Creo etc.) to create detailed mechanical designs. Model and design complex electro-mechanical parts, including plastics, sheet metal, insulators, magnetic components, and high-voltage connectors. Perform mechanical design analysis, including structural FEA, thermal CFD, vibration, and fatigue assessments. Solve packaging challenges involving electrical isolation, sealing, thermal dissipation, EMI/EMC shielding, and mechanical shock/vibration. Define and execute validation test plans including structural, thermal, and environmental testing. 2D drawings with GD&T for production and inspection. Create engineering documentation, tolerance stacks, BOMs, and release packages through PLM systems. Collaborate cross-functionally with electrical, thermal, Firmware and controls, manufacturing, test, and industrial design teams. Work closely with suppliers to optimize DFM, DFA, and tooling strategies for high-volume production. Lead prototype development, fabrication, assembly, and mechanical testing of new designs. Support root-cause analysis of design issues in pilot or production builds and lead iterative improvements. Drive trade studies to inform system-level decisions on design architecture, materials, and manufacturing processes. Guide selection for structural, thermal, and electrical compatibility in high-voltage environments. Contribute to the layout and design of integrated cooling systems including cold plates, thermal interfaces,