Senior Sales Engineer

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

Job Overview

The Senior Sales Engineer reports to the Senior Sales Engineering Manager and serves as a senior technical contributor within the sales cycle for solution architecture, estimating, and system integration strategy.

As a member of the Sales Engineering team (a subset of Project Delivery), this role exercises independent technical judgment to develop cost-optimized, execution-ready solutions aligned with Mainspring’s linear generator capabilities. The Senior Sales Engineer is accountable for architectural integrity, commercial rigor, and seamless transition from concept through execution.

Responsibilities

• Develop system architecture, preliminary designs, and cost estimates from concept through execution handoff
• Articulate and support sound technical approaches, ensuring appropriate design integration and tradeoff evaluation
• Produce complete, accurate, and timely proposal packages across multiple concurrent projects
• Build well-supported cost estimates, proactively communicate risks, and incorporate market inputs into pricing assumptions
• Support customer meetings, site walks, and solution presentations as the technical subject matter expert
• Communicate technical concepts in clear, structured, and solution-oriented formats across customer and internal stakeholders
• Collaborate with Engineering, Product, Controls, Commissioning, and Project Management to support technical feasibility and execution alignment
• Contribute to peer design reviews to share technical perspective and strengthen overall solution quality

Qualifications

• Bachelor’s degree in Electrical/ Mechanical/ Systems/ Energy Engineering
• 7+ years of experience in sales engineering, applications engineering, front-end engineering development (FEED) or cost estimating within electrical power systems or related industries
• Experience in distributed energy, solar, batteries, fuel cells, microgrids, or related technologies preferred
• Familiarity with electrical power systems, three phase inverters, protection relays, and the physics of grid integration
• Strong understanding of standard electrical drawings such as wiring diagrams, electrical schematics, and one-lines
• Ownership Mentality: Proactive in identifying risks and comfortable advocating for the resources needed to solve them
• Ability to travel nationally (~25%)