Fluence has launched a new AC-based modular battery storage platform for delivery in the fourth quarter of this year.
The US-headquartered energy storage system integrator and digital energy services provider unveiled Fluence Smartstack yesterday (13 February) at an investor event.
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The launch had been previewed a few days earlier when Fluence announced its latest financial results. The company said that it would improve competitiveness in an increasingly crowded field.
With the first deliveries to customers to begin in Q4 2025, CEO Julian Nebreda said the “benefit of this new platform” would be seen from the first quarter of the following year, talking up its design features in an earnings call.
Claimed advantages include “industry-leading” energy density, a “significant” reduction in customers’ required investments and total cost of ownership, while combination with Fluence’s digital services and software means systems can achieve 99% availability, Nebreda said.
In a recent ESN Premium article, various energy storage industry experts and executives discussed the shift toward system integrators and manufacturers more commonly offering AC block solutions, which integrate power electronics and other balance of plant within the BESS enclosure, in addition to or instead of DC blocks. As highlighted by Fluence’s latest release, advantages of the AC block include higher energy density and increased asset availability (Premium access).
Up to 7.5MWh capacity using 300Ah cells
The company claimed the product achieves approximately 30% higher energy density than typical AC solutions and that its flexible, modular design can be tailored for projects requiring 2-hour- to 8-hour discharge duration at full rated power.
Fluence said Smartstack, aimed at grid-scale battery energy storage system (BESS) applications, is now commercially available worldwide.
The solution allows customers to combine multiple units of a Battery Pod, containing the battery cells, onto Fluence’s new Smart Skid, which integrates cooling equipment, power control system hardware, cabling and monitoring. Fluence said the design enables easy maintenance as pods can be removed for replacements or repair and the skid is readily accessible.
In essence, the pods fit on top of the skid, meaning the solution is designed to be configurable to different capacities and durations as projects require. That enables more megawatt-hours to be fitted into a smaller footprint, Fluence claimed. The modular AC block architecture integrating the inverter and other balance of plant equipment within the enclosure is currently patent pending.
Within the industry’s ongoing appetite for higher energy density solutions, Fluence claimed the Smartstack design enables up to 7.5MWh storage capacity using 300Ah battery cells. According to a datasheet brochure, the dimensions of that capacity would fit a form factor larger than the standard 20ft containerised configuration adopted by most of the industry to date.
The datasheet lists the Smart Skid’s dimensions as 24ft in length by 7.2ft width and 5ft in height, while each Battery Pod comes in at 5.78ft length, 8.3ft width and 8.4ft height. A standard shipping container-sized enclosure would be 20ft long, 8ft wide and 8.6ft in height, so the Smartstack solution would be longer, wider and taller.
Smartstack also integrates the same safety features as the company’s Gridstack product line that was launched in 2020, including large-scale fire testing, but “now at a much higher energy density,” Fluence VP of product and programme management Mark Berger said.
“These advanced safety features work together to prevent, detect, and contain thermal events, minimising potential damage and downtime,” Berger said.
‘Accelerated product development in response to Chinese competitors’
With much global attention being paid to supply chains and logistics, Fluence also aims to improve competitiveness in that area, claiming Smartstack components can be sourced or manufactured regionally.
The company’s recent financial results, for the first quarter of its fiscal year 2025 (FY2025) ending 31 December 2024, showed a 49% year-on-year decline in quarterly revenues and Fluence lowered its FY2025 revenue guidance by US$600 million.
While the quarterly dip was attributed to more seasonal demand in FY2025 than the more consistent profile of the previous FY, and the lowered guidance was primarily attributed to delays in signing contracts for projects in Australia, Fluence also said it would likely feel the impact of increased competition in the energy storage space this year.
In the earnings call, CEO Nebreda said Fluence has also accelerated its product development programme “in response to the increased competition from Chinese players.”
Along with its localised and domestic content strategy, particularly in the US, where it began manufacturing of its battery modules in September and is sourcing cells from a US-based third-party factory, it appears Fluence is positioning Smartstack, “the most substantial generational change for Fluence since the introduction of the Gen 6 Cube (the modular block, which powers the Gridstack),” according to CEO Nebreda, as a key aspect of its competitive push.
Conference call transcript by Seeking Alpha.
This article has been amended from its original form to include the dimensions of the Smartstack Battery Pod and Smart Skid, as well as to reflect that a datasheet brochure has been made available by Fluence.
