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

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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.

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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].”

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