ON.energy is building the backbone of energy and AI infrastructure powering grid-safe data centers and mission-critical facilities. The company supplies and operates hyperscale power systems that solve the toughest resilience challenges, delivering custom solutions for AI data centers, mission-critical facilities, and front-of-the-meter assets. ON recently announced a 5GW partnership, with 3GW currently under construction across multiple hyperscale data center campuses. With patented technology and proprietary software, ON.energy develops projects worldwide that set new benchmarks for resilience.
Role Summary
At ON.energy, the Simulation Engineer for Battery Energy Storage Systems (BESS) is responsible for building, running, and validating simulation environments that ensure our energy management software performs correctly before it ever touches real hardware. This is a simulation-first role where the primary deliverables are high-fidelity Software-in-the-Loop (SIL) and Hardware-in-the-Loop (HIL) test environments that give our engineering teams confidence in every algorithm, control loop,



and protection function we deploy.
The idóneo candidate is an early-career engineer with a solid foundation in dynamic systems, power electronics, or control theory, and a hands-on curiosity for building models that accurately reflect real BESS behavior. This role offers direct mentorship from senior R&D; engineers and access to industry-leading real-time simulation hardware.

Key Responsibilities
SIL Simulation & Validation
Develop and maintain Software-in-the-Loop (SIL) environments in MATLAB/Simulink to validate energy management algorithms, protection logic, and control strategies prior to hardware integration.
Build high-fidelity battery system models in Simulink — including cell electrochemistry, thermal dynamics, State of Charge (SoC), and State of Health (SoH) — and continuously improve model fidelity against measured data.
Design and execute automated regression test suite

📌 Junior Simulation Engineer (Ciudad de México)
🏢 On.Energy
📍 Ciudad de México