Tales of BESS #5 - Case Study: Safety & Performance Analysis under TAM contract

Safety & Performance Analysis under TAM contract: 32MW / 32MWh (UK)

The BESS is operated by the Technical Asset Management team of Greensolver on the behalf of the Asset owner. The BESS is 32MW / 32MWh located in UK.

As part of the TAM scope of services, Greensolver team led an analysis to check Safety & Performance status of the plant, throughout a 8 months operational period.

Greensolver team conducted the analysis with the support of an Analytic tool provided by a third-party partner.

Thanks to the raw data: Temperature, Voltage and Current given by the SCADA at Battery rack level, Greensolver was able to analyse :

• State-of-Safety: by tracking over-voltage / over-temperature / cell imbalance to prevent Thermal Runaway
• Performance: by checking estimation and accuracy of SOC and SOH / BMS faults
• Lifetime: by checking operational condition vs battery OEM requirements (temperature, C-Rate)

This Safety & Performance analysis allowed to highlight issues, which have been then raised to the battery OEM :

• State-of-Safety: frequent cell imbalance caused by weak cells, which could then lead to over-voltage and over-charge in the Battery cells and at the end Thermal Runaway
• Performance: remaining useful capacity (SOH) below the warranty of the battery OEM / frequent faulty measurement of the BMS, leading to SOC deviation (wrong voltage measurement)
• Lifetime: higher temperature of the battery module than recommended, which could accelerate the ageing

Written by David Roissé