ESS Tech Inc (GWH)

ESS Tech, Inc.'s stock declined by 65.19% from March 24, 2025, to March 23, 2026, and underperformed both the broader US Market and the US Electrical industry over the past year. Key corporate events include the announcement of Q4 and full year 2025 financial results, reporting a net loss of $23.98 million for Q4 2025 and negative revenue of $1.59 million. ESS Tech announced an agreement to join the Salt River Project and Google Long Duration Energy Storage Collaboration. Randall Selesky was appointed as Chief Commercial Officer. ESS acquired intellectual property and assets from VoltStorage GmbH. ESS Tech filed a follow-on equity offering of approximately $15 million. Drew Buckley was appointed as the new Chief Executive Officer. The company bolstered its liquidity with a $40 million financing in October 2025, an $8.6 million at-the-market equity raise, and a $15 million registered direct offering completed in January 2026.

Demand for ESS Tech's products and services is primarily driven by the growing need for long-duration energy storage, fueled by global decarbonization goals, the push for grid flexibility, and increased investment in clean energy infrastructure. The company's iron flow batteries address the mismatch between electricity production from renewable sources and electricity usage, which can lead to curtailment. The global long-duration energy storage market is projected to experience significant growth.

ESS Tech, Inc. develops and manufactures long-duration energy storage systems using iron flow battery technology, which utilizes earth-abundant materials. The company's major products include the Energy Warehouse, Energy Center, and Energy Base. ESS Tech generates revenue through the sale of these hardware systems, supplemented by engineering and maintenance services.

Headquartered in Wilsonville, Oregon, ESS Tech, Inc. designs and produces its iron flow batteries for commercial and utility-scale energy storage applications globally. The company serves a diverse customer base spanning North America, Europe, Asia, and Australia. Recent deployments and partnerships have expanded its footprint in California and Missouri.

ESS Tech has received positive recognition, being named a TIME Top GreenTech Company and one of Fortune's Most Innovative Companies in America for 2025. The company's iron flow batteries are highlighted for their safety, sustainability, and use of earth-abundant materials. The Energy Center product line has achieved industry-leading certifications, including ETL certification to the UL 9540 standard and compliance with the MESA-Device profile test. The company's global fleet of long-duration energy storage solutions surpassed 2.5 GWh of transacted energy. Despite these achievements, the company has faced concerns regarding deep operational losses, thinning cash reserves, and a history of missed targets.

ESS Tech, Inc. operates with a hybrid ownership model, combining significant influence from strategic and venture capital investors with a substantial, albeit fragmented, institutional float. Approximately 18.65% to 23.18% of the company's stock is held by institutional investors, 3.84% by insiders, and a significant portion (72.98%) by public companies and individual investors. Major institutional owners include Softbank Group Corp, Alyeska Investment Group, L.P., Vanguard Group Inc, Geode Capital Management, Llc, Green Alpha Advisors, LLC, Jane Street Group, Llc, Pathstone Holdings, LLC, Gsa Capital Partners Llp, BlackRock, Inc., Honeywell International Inc., and Breakthrough Energy Ventures LLC.