Senior BESS Engineer

The Green Recruitment Company.; Greater London; On-site; GBP 90,000 - 130,000; Full time

Job summary

The Green Recruitment Company seeks a Senior BESS Engineer to act as the technical lead for battery energy storage systems, including standalone and solar co-located projects within the UK. You will shape design, procurement, construction, commissioning and operation to meet performance guarantees such as availability and round-trip efficiency.

Responsibilities include defining technical requirements, interfacing BESS with PV, driving grid connection studies, and mentoring teams on storage tech.

Qualifications

• 5+ years in utility-scale BESS engineering across design, procurement, construction or operations.
• Deep knowledge of BESS architecture: cells, racks, PCS/inverters, EMS/BMS/SCADA, thermal, fire protection.
• Experience reviewing contractor designs and witnessing tests.
• Familiarity with IEC, UL, NFPA 855 battery safety standards.
• Ability to translate data into clear technical decisions.

Responsibilities

• Define BESS technical requirements and sizing, including MW/MWh, duration, AC/DC coupling.
• Define interfaces between BESS and co-located solar PV systems.
• Provide input into grid connection studies and engaging DNO/NESO.
• Develop and maintain BESS technical specs and reference designs.
• Oversee supplier evaluation, warranties, degradation, and RTE guarantees.
• Support contract negotiations with technical schedules and requirements.
• Monitor tech developments and establish BESS standards and best practices.
• Witness factory acceptance tests, site inspections and commissioning.
• Manage defects, variations and contractual claims.
• Monitor performance metrics: availability, capacity, degradation, RTE.

Skills

BESS engineering

Project leadership

Grid integration

Thermal management

Fire safety standards

Data analysis

Education

Electrical/Mechanical/Chemical/Energy engineering degree

Job description

A leading European renewable energy developer and independent power producer is seeking a Senior BESS Engineer to act as the technical lead for battery energy storage systems, including both standalone and solar co-located projects.

The role will ensure BESS projects are appropriately designed, procured, constructed, commissioned and operated, with responsibility for protecting key performance guarantees including power, energy, availability and round-trip efficiency.

Key Responsibilities:

Design & Development

• Define BESS technical requirements and sizing, including MW/MWh, duration, AC/DC coupling and augmentation strategy.

• Define technical interfaces between BESS and co-located solar PV systems.

• Provide technical input into grid connection applications, studies and DNO/NESO engagement.

• Develop and maintain BESS technical specifications and reference designs.

Procurement & Technology

• Technically evaluate BESS suppliers and integrators, including cell chemistry, PCS, thermal management, fire safety, warranties, degradation and RTE guarantees.

• Support supply, EPC and LTSA contract negotiations, with responsibility for technical schedules and requirements.

• Develop technology and pricing roadmaps using market and supplier feedback.

• Monitor technology developments and supplier bankability.

• Establish BESS technical standards and best practices while mentoring colleagues on storage technology.

Construction & Commissioning

• Review contractor designs, drawings, calculations and technical submissions.

• Oversee factory acceptance testing, site inspections, installation quality and commissioning.

• Witness and verify Taking Over, IAC and FAC testing, including capacity and RTE testing.

• Manage technical defects, snagging and performance issues.

• Provide technical input into variations, delays and contractual claims.

Operations & Performance

• Monitor BESS performance, including availability, capacity retention, state of health, RTE, auxiliary consumption and alarm/fault trends.

• Manage performance guarantees, warranties, degradation claims and O&M/LTSA provider performance.

• Support BESS optimisation and trading strategies.

• Assist with spares, augmentation and end-of-life planning.

Safety, Compliance & Governance

• Ensure BESS design and operation comply with applicable UK standards, regulations and battery fire-safety requirements.

• Report technical risks to senior management, lenders and insurers.

• Support lender technical adviser activities and technical due diligence.

Essential Experience & Skills:

• 5+ years' experience in utility-scale BESS engineering, covering design, procurement, construction, commissioning and/or operations, ideally within an owner, developer, IPP or technical advisory environment.

• Strong understanding of BESS architecture, including cells and racks, PCS/inverters, transformers, EMS/BMS/SCADA, thermal management and fire protection.

• Understanding of BESS performance metrics and guarantees, including availability, capacity retention, degradation, RTE and auxiliary consumption.

• Experience reviewing contractor designs and witnessing factory, site and commissioning tests.

• Knowledge of relevant battery safety standards such as IEC, UL and NFPA 855 or equivalent.

• Ability to analyse operational data and provide clear, decision-ready technical recommendations.

• Strong collaboration skills across grid, contracts, development and asset management teams.

• Degree in electrical, mechanical, chemical, energy engineering or a related discipline.

Desirable Experience

• Experience with solar PV and BESS co-location, including shared grid connection and control interfaces.

• Knowledge of the GB BESS market and storage revenue streams.

• Experience with BESS supply, EPC and LTSA contracts and technical performance guarantees.

• Knowledge of battery dispatch, trading, optimisation, degradation and augmentation planning.

• Experience using AI tools such as Microsoft Copilot or Claude for technical analysis, document review and reporting.

• Chartered or professionally qualified engineer status (CEng or equivalent), or working towards professional accreditation