A trio of announcements in the long-duration energy storage (LDES) sector, from RedoxBlox, Eos Energy Enterprises and ESS Inc.

The four most high-profile energy storage system (ESS) companies that listed via SPAC mergers – Eos, Energy Vault, ESS Inc and Stem – have seen their share prices fall by an average of 80% since going public.

Iron-saltwater flow battery company ESS Inc looks set to deploy by far its largest project to-date, a 50MW/500MWh system at a renewables hub from German energy firm LEAG, with potential for more.

ESS Inc. has received UL1973 certification for the battery modules in its utility and industrial flow battery energy storage systems.

ESS Inc ended 2022 with nearly 800MWh of annual production capacity for its iron flow battery, although had a relatively poor last financial quarter with just US$15,000 in revenue.

Malaysia-based Reservoir Link has signed a memorandum of understanding (MOU) with an unnamed US-based ‘Iron Flow Long Duration Energy Storage provider’, while ESS Inc tells Energy-Storage.news it is ‘actively exploring’ opportunities in Reservoir Link’s markets.

ESS Inc has recognised revenues for the first time since publicly listing, while closing in on a 750MWh targeted annual production capacity.

Construction has begun of a factory for long-duration flow batteries using iron and saltwater electrolyte in Queensland, Australia.

Iron flow battery company ESS Inc continues to await recognition of revenues, but has “strong confidence” in its trajectory towards profitability.

Energy-storage.news caught up with executives from two long-duration flow battery energy storage providers, ESS Inc. and Invinity Energy Systems, at the Energy Storage Summit 2022.