Energy storage technology provider Fluence Energy has received independent validation of the reliability of its battery energy storage systems, with a review by global assurance and energy expert DNV confirming fleet availability of 99.3% across examined projects.
The assessment focused on Fluence-operated battery energy storage systems with capacities of 50 MW and above. DNV reviewed fleet-level availability data, contractual calculation methodologies, and operational records from selected projects to verify performance claims.
The review also confirmed Fluence’s internal findings, which reported a MW-weighted fleet availability of 98.7% across its global portfolio of energy storage projects.
Fluence said the results demonstrate the reliability of its systems in delivering power when needed, a critical factor as energy storage becomes increasingly important for grid stability and renewable energy integration.
“Customers invest in energy storage to deliver power exactly when it is needed, and every minute of downtime represents lost revenue and grid vulnerability,” said John Zahurancik, Chief Customer Success Officer at Fluence. He noted that the independent validation provides customers with a trusted benchmark for evaluating energy storage performance.
The study was designed to improve transparency around battery storage reliability by applying a consistent methodology across different markets, operating conditions, and project types. DNV independently evaluated the assumptions, calculations, and operational data used in the analysis.
Industry availability figures for battery energy storage systems are often reported between 95% and 98%, but differing methodologies can make direct comparisons difficult. According to DNV, standardized and independently verified performance metrics are becoming increasingly important as battery storage assets play a larger role in maintaining grid reliability.
“As batteries take on a larger role in ensuring grid reliability, there is increasing need for greater confidence in how performance is measured and understood,” said Marion Hill, Executive Vice President and Region Director for Energy Systems North America at DNV.
The companies highlighted that even small differences in system availability can have a substantial impact on project economics, influencing revenue generation, operating costs, and long-term asset value.
The review is being positioned as one of the industry’s most comprehensive independent assessments of fleet-level battery storage availability. Fluence believes such transparency will become increasingly valuable as electricity demand grows due to electrification, industrial expansion, and the rapid rise of artificial intelligence-driven data centers.
With energy storage playing a critical role in supporting modern power systems, independently validated performance data could help utilities, developers, and investors identify technologies capable of delivering dependable capacity at scale.
