Electrical Engineer - Balance of System Integration Engineer

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.

Mainspring is seeking a versatile Systems Integration Engineer to lead the architectural design and deployment of the hardware‑to‑software interface for our Linear Generator sites. You will serve as a cross‑functional technical lead for Balance of System (BoS) strategy, developing modular hardware platforms that scale from small microgrids to utility‑scale power plants. In this capacity, you will own the full design lifecycle and vendor management for our Industrial Control Panels (ICP), which serve as the critical communication and I/O hub for our Linear Generator sites.

• Manage the full design cycle for NEMA 3R and 4X control cabinets, including component selection for industrial PCs, managed switches, and I/O modules
• Design and implement I/O mapping for control and safety systems, including E‑Stop synchronization, black start triggers, and ground‑fault detection using Modbus/TCP‑based edge devices
• Architect robust site‑level communication networks, including managed VLAN structures and fiber/copper hybrid topologies for high‑demand environments
• Be the primary technical interface for outsourced design firms and panel manufacturers, ensuring high reliability designs, UL 508A compliance and manufacturing scalability
• Lead technical reviews and coordinate with contract manufacturers to drive cost‑reduction, design‑for‑manufacturability (DFM), and UL 508A certification
• Manage the physical and electrical interfaces between the linear generator and external balance‑of‑system equipment, such as external grid‑tied inverters

• Bachelor's or Master's degree in Electrical Engineering or a related field
• 8+ years of demonstrated experience developing industrial control panels and integrated systems
• Strong understanding of DC/AC power distribution, relay logic, and industrial communication protocols (Modbus, Ethernet/IP)
• Demonstrated experience integrating complex hardware platforms with…