Director of Mechanical Engineering

Mainspring Energy is a power infrastructure company that designs and manufactures the Linear Generator, a novel primary power solution that delivers firm, flexible, and low-emissions electricity at the point of need. The company serves a wide range of markets including utilities, data centers, enterprise customers, and industrial operations, offering modular units that can be deployed quickly and scaled from hundreds of kilowatts to hundreds of megawatts. The Linear Generator is capable of operating on multiple fuels including natural gas, biogas, and field gas, and is designed to transition seamlessly to zero-carbon fuels over time.

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

Director of Mechanical Engineering

We are seeking a Director of Mechanical Engineering to lead a substantial portion of the team scaling the Linear Generator — a first-of-kind distributed power platform that converts a low-temperature, flameless reaction directly into electricity using high-frequency linear motion instead of rotating machinery. The system integrates reciprocating pressure-driven assemblies, air-spring return chambers, precision alignment systems, and linear electromagnetic machines within a modular 250 kW-class packaged unit. It operates under cyclic loads, tight sealing constraints, thermal gradients, structural dynamics, and grid-interactive performance requirements typical of commercial power generation equipment.

Reporting to the VP of Mechanical Engineering, this role is being created to expand leadership capacity, elevate risk visibility, and enable disciplined scaling of a growing hardware portfolio.

You will own ~40–50% of the mechanical organization’s active projects and lead ~25 direct and indirect reports, with scope expected to grow. Your teams will oversee multiple core subsystems that are tightly coupled and reliability-critical.

Success requires both deep mechanical intuition and strong organizational leadership. You will strengthen technical rigor, improve prioritization across 50+ active efforts, and build execution systems that allow the organization to scale without sacrificing engineering excellence.

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.

Core Responsibilities

Leadership of ~25 engineers (direct and indirect), including managers

40–50% of the mechanical project portfolio

Accountability for multiple core subsystems

Early identification and mitigation of subsystem and program-level risks

Strong engineering review discipline (FMEA, DVP&R, tolerance analysis, ECO governance)

Partnership with Manufacturing and Supplier Quality to support at-scale production

Development of future engineering leaders

Qualifications

18+ years delivering complex industrial or energy hardware

Experience in high-volume, at-scale environments

Leadership of 15–30+ engineers (direct + indirect)

Strong judgment around technical and program risk

Ability to balance architecture evolution with production realities

Management experience required; Director title not mandatory

Senior-level design credibility to lead experienced engineers