ESS Tech, Inc. (NYSE: GWH), a leading manufacturer of long-duration iron flow energy storage solutions, announced the closing of its registered direct offering with institutional investors, raising approximately $15 million. The transaction, which closed on Jan. 30, 2026, involved the sale of 8,571,428 shares of common stock and pre-funded warrants at a price of $1.75 per share, a premium to the Jan. 28, 2026 closing price. Aegis Capital Corp. served as the exclusive placement agent for the offering. Net proceeds, together with existing cash, are expected to be used for general corporate purposes and working capital, according to the press release.
The offering underscores ESS Tech’s ability to access capital markets amid growing demand for energy storage solutions. The company specializes in iron flow batteries that utilize iron, salt, and water—materials that are abundant, safe, and sustainable. This technology is designed to provide long-duration energy storage, which is critical for integrating renewable energy sources like solar and wind into the grid. By enabling energy security and reliability, ESS’s systems help utilities and commercial customers manage increasing energy demand without power disruptions.
The capital raise comes at a time when the energy storage sector is experiencing rapid growth, driven by the global push toward decarbonization and grid modernization. ESS Tech’s iron flow batteries offer a differentiating value proposition: they are non-flammable, have a 25-year design life, and can discharge for up to 12 hours, making them suitable for both front-of-the-meter and behind-the-meter applications. The company’s mission to accelerate decarbonization safely and sustainably aligns with policy trends in the U.S. and abroad, where governments are investing heavily in clean energy infrastructure.
For ESS, the $15 million infusion provides additional runway to scale manufacturing, expand its project pipeline, and support ongoing operations. The company has been deploying its systems across various markets, including utility-scale projects and microgrids. As noted in the announcement, the offering’s pricing above the prior closing price indicates strong institutional interest in the company’s long-term prospects.
The offering was executed as a registered direct offering, which allows companies to raise capital efficiently without the typical delays of a public offering. This structure is often used by public companies to secure funding from accredited investors. The net proceeds, combined with existing cash reserves, are expected to strengthen ESS’s balance sheet as it continues to commercialize its technology.
Investors and industry analysts will be watching how ESS deploys the capital to capture market share in the expanding energy storage market. The company’s focus on iron flow technology positions it as a key player in the long-duration storage segment, which is essential for achieving renewable energy targets. For more information about ESS Tech, visit www.essinc.com.
