Fluence launches ‘Ultrastack’ BESS solution aimed at storage-as-transmission applications

LinkedIn
Twitter
Reddit
Facebook
Email

Fluence has launched a battery storage solution aimed at the market for energy storage as a transmission asset, called ‘Ultrastack’.

The global energy storage manufacturer, system integrator and clean energy digital services provider revealed the Ultrastack yesterday.

It is designed for applications that help transmission and distribution (T&D) system entities to lower the costs of operating and upgrading their networks, with batteries used to increase utilisation of power lines, reduce the curtailment of renewable energy on the grid and reduce grid congestion.

Fluence described it as the company’s highest-performance energy storage product to date. That’s because it needs to be, according to Fluence VP of EMEA region sales and market development Brian Perusse. Grid operators have extremely tight requirements to keep their networks running safely and smoothly, often answerable directly to regulators and governments if anything goes wrong.

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

Essentially, storage-as-transmission, as Fluence calls it, places batteries into the category of critical grid infrastructure and that means the Ultrastack has 99% system uptime to meet expected requirements on  availability, enhanced cybersecurity measures and more – taking a lot of the features and functionality of BESS equipment “to a whole new level,” Perusse said in an interview with Energy-Storage.news.

The company has patent pending for Ultrastack’s control applications, allowing it to deliver system stabilisation and utilisation services such as synthetic inertia, and power oscillation damping.

Fluence is already working on two high-profile storage-as-transmission projects in Europe: a 200MW/200MWh project with Lithuanian grid operator Litgrid, and a 250MW/250MWh so-called ‘Grid Booster’ project in Germany with transmission operator TransnetBW.  

“Storage-as-transmission is starting to have a foothold in Europe,” Perusse said with regard to those projects.

“They might look like storage projects but the technical requirements are substantially different from any other storage deployed in any other markets. You have a higher availability, reliability, cybersecurity requirements, it becomes critical grid infrastructure at the transmission level, and it’s quite different in its requirements [to other projects].”

Read Next

September 21, 2026
System integrator Fluence and lithium-ion battery OEM Eve Energy have struck a massive 206GWh battery supply framework agreement for 2027-31, one of the largest deals of its kind ever announced.
September 18, 2026
The US has pledged financial support towards an existing 400MWh battery energy storage system (BESS) portfolio in Ukraine.
September 17, 2026
Fluence has revised downward its fiscal year 2026 (FY2026) guidance, attributing the financial hit largely to US supply chain delays.
Premium
September 16, 2026
On 26 August, US President Donald Trump banned the import of inverters, transformers and other power equipment citing a potential risk to US grid security, via emergency executive order (EO).
September 7, 2026
Pakistan’s National Electric Power Regulatory Authority (NEPRA) has approved plans to require bidders in a renewable energy auction to include energy storage.