Senior BESS Engineer - Sizing & Battery Technology

Hydrogen Group; Juno Beach (FL); On-site; USD 44,000 - 73,000; Full time

Job summary

Hydrogen Group is seeking a Senior BESS Engineer to lead utility-scale sizing and technology evaluation for energy storage projects. You will drive end-to-end sizing, assess degradation, temperature effects and optimization opportunities across PCS, interconnection, and substation interfaces.

The role emphasizes data-driven engineering with tools like Python, Excel/VBA and Power BI, plus collaboration with engineering and development teams to guide technology choices and CAPEX estimates.

Qualifications

• Bachelor's or Master's degree in an engineering discipline.
• Demonstrated experience with utility-scale BESS.
• Strong expertise in BESS sizing, optimization and thermal effects.
• Knowledge of battery technologies and BESS architecture.
• Experience evaluating battery/PCS technologies.
• Ability to communicate findings across teams.

Responsibilities

• Provide technical leadership for utility-scale BESS sizing methodologies and optimization.
• Develop end-to-end BESS sizing from interconnection to battery equipment.
• Maintain sizing tools, inputs, and technical guidance.
• Review sizing results and identify optimization opportunities and risks.
• Deliver sizing recommendations to cross-functional teams.
• Develop and improve engineering tools for BESS sizing and forecasting.
• Apply data analytics and software tools to improve productivity.

Skills

BESS sizing

Optimization

Battery technology

Power electronics

Data analytics

Python

Excel/VBA

Power BI

AI in engineering

Education

Bachelor's or Master's in Engineering

Tools

Python

Excel/VBA

Power BI

Job description

Senior BESS Engineer - Sizing & Battery Technology

Contract: 12 Months

Pay Rate: Up to $52.96 per hour

We are seeking an experienced Senior BESS Engineer to support a Utility Scale Energy Storage team, providing technical expertise across battery energy storage system (BESS) sizing, optimization, battery technology and power conversion systems (PCS).

This position will serve as a technical Subject Matter Expert supporting utility-scale energy storage projects and the evaluation of existing and emerging storage technologies.

The successful candidate will combine strong engineering fundamentals with hands‑on BESS sizing experience and an innovative approach to engineering tools, automation, data analytics and emerging technologies.

• Provide technical leadership for utility-scale BESS sizing methodologies, assumptions, optimization and project‑specific sizing decisions.
• Develop and optimize end-to-end BESS sizing from the point of interconnection through GSU/substation, PCS/inverters, DC systems and battery equipment.
• Account for system losses, battery degradation, augmentation and overbuild strategies, temperature effects, operating constraints and contractual requirements.
• Ensure sizing solutions align with power purchase agreements and project‑specific technical requirements.
• Develop, maintain and continuously improve BESS sizing methodologies, calculators, assumptions and technical guidance.
• Maintain accurate records of sizing inputs, assumptions, technical decisions and results throughout project development and execution.
• Review project‑specific sizing results and identify optimization opportunities, risks and potential improvements.
• Provide sizing recommendations to Engineering, Development, Supply Chain and project teams.
• Maintain sizing tools and equipment databases to incorporate current BESS and PCS ratings and technical characteristics.

Battery & Energy Storage Technology Evaluation

• Evaluate existing and emerging battery technologies for utility‑scale applications.
• Perform technical assessments covering degradation, efficiency, available energy, reliability, state of charge (SOC) and state of health (SOH).
• Evaluate battery performance from cell and module level through complete system applications.
• Assess emerging and alternative energy storage technologies for new use cases and regional market requirements.
• Evaluate technologies based on technical maturity, performance, safety, scalability, supply chain readiness and commercial viability.
• Develop preliminary system sizing and CAPEX estimates for alternative energy storage technologies.
• Support technology selection, business‑case development, pilot projects and commercial deployment decisions.
• Analyze vendor RFP and RFI information to track technology developments, product roadmaps, performance and commercial readiness.
• Summarize technical findings and provide recommendations to engineering and management teams.
• Develop and improve engineering tools used for BESS sizing, technical evaluations and battery performance forecasting.
• Automate repetitive engineering calculations and workflows where appropriate.
• Apply data analytics and software‑based tools to improve engineering productivity, consistency and decision‑making.
• Utilize tools such as Excel/VBA, Python, Power BI, low‑code platforms and AI‑assisted engineering applications where appropriate.
• Identify practical applications for emerging technologies and AI within energy storage engineering.
• Partner with software development and technical teams to translate engineering methodologies into scalable digital tools and automated workflows.

Qualifications

• Bachelor's or Master's degree in Electrical Engineering, Mechanical Engineering, Chemical Engineering, Materials Engineering, or a related technical discipline.
• Demonstrated experience with utility-scale battery energy storage systems (BESS).
• Strong expertise in BESS sizing and optimization, including AC/DC sizing, system losses, degradation, augmentation/overbuild strategies, thermal impacts and project‑specific operating requirements.
• Knowledge of battery technologies and utility‑scale energy storage system architecture.
• Experience evaluating battery and/or PCS technologies.
• Strong analytical and engineering problem‑solving skills.
• Excellent project management, communication and organizational capabilities.
• Ability to communicate complex technical findings and recommendations across engineering and business teams.

Preferred Experience

• Experience with emerging or alternative storage technologies such as flow batteries, multi‑day energy storage, sodium‑ion batteries, fuel‑cell‑like technologies or supercapacitors.
• Knowledge of power electronics, including PCS/inverters, IGBT and SiC technologies.
• Experience working with major or emerging battery and PCS suppliers.
• Experience applying Python, Excel/VBA, Power BI, automation, AI or advanced data analytics to engineering applications.
• Experience developing engineering calculation, sizing or performance‑prediction tools.
• Understanding of utility‑scale energy storage commercial and project requirements.
• Strong interest in emerging battery technologies and continuously improving existing engineering processes.

Some travel to battery manufacturing facilities may be required to support technology assessments.

Desired Skills and Experience

Battery Energy Storage Systems (BESS), Energy Storage, Battery Technology, BESS Sizing, Power Conversion Systems, Battery Degradation, Power Electronics, Renewable Energy, Python, Data Analytics