System Firmware Controls Engineer - EMS & SCADA, BESS

Enphase Energy is a global energy technology company and a leading provider of solar, battery, and electric vehicle charging products. Founded in 2006, our innovative microinverter technology revolutionized solar power, making it a safer, more reliable, and scalable energy source. Today, the Enphase Energy System enables users to make, use, save, and sell their own power. Enphase is also one of the most successful and innovative clean energy companies in the world, with more than 80 million products shipped across 160 countries.

Join our dynamic teams designing and developing next‑gen energy technologies and help drive a sustainable future!

As a Staff System Firmware Controls Engineer, you will design and develop the system‑level control firmware and software for the Energy Management System (EMS) and SCADA layer of our MW/MWh‑scale Battery Energy Storage Systems (BESS) serving data centers, spanning outdoor cabinets and containerized platforms. You will build the master site controller that coordinates the PCS (inverters), BMS, and thermal subsystems, and interfaces the BESS with utility and grid SCADA and higher‑level plant controllers.

This role requires hands‑on expertise in embedded and real‑time controls, EMS control algorithms, SCADA and industrial communications, and BESS grid‑code compliance. You will work closely with inverter, BMS, thermal, systems, safety, and cloud/software teams to ensure the product meets performance, reliability, interoperability, compliance, and cost targets ― delivering production‑ready designs from concept through deployment and commissioning. You will also mentor junior engineers and contribute to the team’s technical direction.

• Design and develop system‑level control firmware and software for the BESS EMS and master site controller.
• Implement real and reactive power dispatch, state‑of‑charge (SOC) and state‑of‑health (SOH) management, and coordination of multi‑vendor subsystems (PCS, BMS, thermal) to meet site and grid requirements.
• Develop control logic for grid services such as frequency response (PFR/FFR), voltage/AVR regulation, capacity firming, peak shaving, energy arbitrage, and black start.
• Integrate the BESS control system into utility, ISO/TSO EMS/SCADA systems and higher‑level plant controllers.
• Implement and maintain industrial communication interfaces using Modbus, DNP3, OPC-UA, MQTT, and IEC 61850.
• Define and validate controls specifications, functional descriptions, points lists, and data‑integration mappings and telemetry for monitoring, control, and historian/data‑logging needs.
• Ensure real and reactive power commands comply with interconnection agreements (LGIA), power purchase agreements (PPA), and grid codes (IEEE 1547, UL 1741‑SB).
• Apply cybersecurity and IT/OT best practices to controller and SCADA network architecture.
• Develop unit and system test software, and validate control behavior using simulation and hardware‑in‑the‑loop.
• Support site bring‑up, commissioning, witness testing, and acceptance with utility and AHJ stakeholders.
• Organize thorough PR reviews, documentation rigor, and well‑managed release branches.
• Accelerate firmware and software development and testing flow utilizing AI tools.
• Mentor junior engineers and contribute to the team’s technical direction.

• BS/MS in Electrical Engineering, Computer Engineering, Controls Engineering, or a related field.
• 8+ years developing embedded/system firmware or control software, preferably for power systems, BESS, microgrids, or grid‑connected products.
• Strong experience with EMS, site/plant controllers, or SCADA systems for energy storage or power generation.
• Proficiency in C, C++, and Python; familiarity with IEC 61131‑3 and/or C# is a plus.
• Strong experience with industrial communication protocols (Modbus, DNP3, OPC-UA, MQTT, and IEC 61850).
• Strong understanding of BESS architecture and coordination with BMS, PCS, and thermal derating logic.
• Knowledge of grid‑services use cases (PFR/FFR, AVR, capacity firming, arbitrage, black start) and ISO market participation (e.g., CAISO, ERCOT, ISO‑NE).
• Working knowledge of grid and safety standards…