German power firm Uniper has entered into a conditional supply contract with organic solid flow battery company CMBlu Energy for the delivery of at least 5GWh of its technology.
The long-term framework agreement runs until 2037 and gives Uniper the option to take delivery of battery systems from CMBlu in tranches of at least 100MWh each, starting in 2027.
It follows a site acceptance test (SAT) of CMBlu’s battery system by Uniper. Both companies are headquartered in Germany.
CMBlu’s SolidFlow battery is based on the unique and patented combination of organic redox flow technology with solid-state storage materials and is specifically designed for market-driven use in the multi-hour range, the company said.
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It claims high cycle stability, a lifespan of several decades and non-flammable electrolytes. It also benefits from the absence of critical raw materials such as lithium, cobalt, or nickel, as with most other non-lithium-based battery technologies.
Uniper first announced plans to pilot CMBlu’s tech at a project in Germany back in 2023. It has also tested other flow battery technologies, including that of Dutch firm Elestor, announced the previous year in 2022. It has also looked at the economic feasibility of large-scale green hydrogen storage, winning a small grant from the EU for a project the same year.
Uniper is a spinout of the larger German-headquartered utility and power firm E.ON.
While the firms didn’t which countries they were targeting for deployments, both are headquartered in Germany so the first projects may well be there.
If so that could represent a shift in appetite for the technology. In 2022, a flow battery executive speaking anonymously lamented that the country’s energy sector ‘did not think it needed flow batteries’, instead believing that a combination of lithium-ion for short-duration and green hydrogen for long-duration would suffice.
However, since then the green hydrogen sector has struggled to scale. Perhaps in related developments, flow batteries appear to have become more viable for large-scale projects. In that time, a flow battery firm VoltStorage raised a €30 million venture loan, a 10MWh project has been completed, and power firm LEAG seriously considered building a 500MWh project using iron flow batteries from ESS Inc.
As well as Europe, CMBlu is also active in the US market. We recently caught up with its North America president Giovanni Damato for an interview on ESN Premium.
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