Fluence Launches 10 MWh Smartstack to Boost Grid-Scale Storage Density

Overview

• Fluence announced the Smartstack 10 MWh configuration on June 24, 2026, expanding its modular Smartstack line that previously included a 7.5 MWh option.
• The company says the new pod design increases core site-level energy density to about 680 MWh per acre so developers can fit more capacity on limited land and lower site footprint needs.
• Fluence reports the 10 MWh system completed Large-Scale Fire Testing and uses compartmentalized pods and containment zones designed to limit thermal propagation and meet UL9540, UL9540A, and NFPA guidance.
• Published technical details show the system uses standard 3XX Ah cells, up to 1,500 V DC and a 690 V AC rating, battery pods of roughly 20,000 kg with a 10,000 kg smart skid, and storage durations from 2 to 8 hours depending on tier.
• Fluence markets the product as commercially available worldwide with integrated Fluence OS controls and an independent-reviewed fleet availability figure of 99.3 percent, a positioning meant to cut balance-of-plant costs up to 40 percent and simplify future cell upgrades.