ON.energy is building the power infrastructure that makes the AI era possible. As AI demand surges past what the grid and traditional data centers can support, ON.energy provides a new class of power technology proven at gigawatt scale and trusted by the world’s leading cloud and AI companies. Our systems are already deployed across 2.5 GW of hyper-scale campuses, validated by top U.S. national labs, and certified for grid-safe operation by major utilities. With real products in the field, we’re scaling faster than the grid can, transforming power from a bottleneck into a competitive advantage for the companies building the future.
We’re looking for a Senior BESS Engineer with project-based engineering experience to lead the BESS and DC Cabinet product design, documentation, project-specific technical compliance and support the development activities related to these products. This is a product focused role—we need someone who can speak fluently about both BESS systems and DC cabinets, ideally have experience with mission critical applications, and interface with project, commissioning and O&M engineering teams.
What You’ll Do- Support the business development team by providing technical proposals e.g. SLDs and GAs that meet the customer’s needs.
- SOC analysis for multiple market applications.
- Compile product technical information packages for the project engineering team.
- Co-lead review and validation of the BESS- and DC Cabinet-related topics during the project execution phase.
- Maintain technical documentation including as-built drawings
- Support product development by capturing design improvement feedback from the different project phases: design, commissioning and O&M.
- Support product development by recommending design approaches and vendors of the main equipment.
- Participate in product design sprints with the development team.
- Participate in the product’s commissioning phase.
- Bachelor’s degree in Electrical Engineering, Power Electronics Engineering, or similar technical field.
- 8+ years of hands-on BESS engineering experience in project-based or industrial settings.
- Proven system-level design experience of MWh scale BESS
- Understanding of BESS systems integration with power electronics equipment.
- Ability to produce and read single lines and general arrangement drawings
- Excellent communication skills across technical and non-technical teams.
- Willing to travel up to 20% for product FAT inspection and site commissioning witnessing.
- Experience with Power Electronics, UPS/mission critical applications or utility-scale infrastructure
For US-based roles - What you’ll get:
- Competitive salary + annual performance-based bonus eligibility
- Medical, dental, and vision insurance
- 401(k) with company match
- Paid time off and company holidays
For Mexico-based roles - What you’ll get:
- Competitive salary + annual performance bonus eligibility
- Christmas Bonus (Aguinaldo): 30 days
- Major medical expenses and life insurance
- Paid time off and holidays (per local policy)
For all roles:
- Professional development and growth opportunities
- Opportunity to grow with a mission-driven team shaping the future of clean energy
- Equal Opportunity: ON.energy is committed to equal employment opportunity and to maintaining a work environment free of harassment, discrimination, or retaliation.
- Accommodations: If you need an accommodation during the application process, email [email protected]
- Benefits vary by role and location and are subject to change.
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