ESS Tech, Inc., a leading manufacturer of iron flow long-duration energy storage (LDES) systems for commercial- and utility-scale applications, has officially raised a sum of $31 million in an insider-led funding.
According to certain reports, the stated package includes approximately $0.9 million in short-term loans from, along with warrants issued to a syndicated group led by members of ESS’ board of directors, as well as the management team alongside an investment fund managed by Yorkville Advisors Global, L.P.
Beyond that, it packs together a production tax credit transaction with an affiliate of SB Energy for approximately $0.8 million, an equipment sale lease back transaction with a U.S. strategic partner for $4.0 million cash with certain closing conditions, and execution of a Standby Equity Purchase Agreement with YA II PN, LTD.
More on this Equity Purchase Agreement would reveal how it gives ESS the right, but not the obligation, to sell up to $25 million of common equity to the Investor at the time of ESS’ choosing, over a 3-year term, subject to certain customary limitations. These limitations include shareholder approval for aggregate issuances in excess of 19.99% of the company’s outstanding shares.
ESS also took this opportunity to unveil its first Energy Base order for an 8 MWh project, which is largely consistent with the strategic shift to a 10+ hour product the company announced back in February. This delivers a rather interesting follow-up to ESS, quite recently, completing all measures to implement streamlined operations and reduced cash requirements.
The same is made evident by its successful drive to achieve a reduction of approximately 80% in monthly cash burn during June, as compared to the monthly average for the first 5 months of 2025.
Making this development even more significant is ESS’ preliminary unaudited financial results for the second quarter of 2025. For better understanding, they represent nearly 300% increase in revenue, combined with a 22% decrease in the cost of revenue, a 37% decrease in operating expenses, a 43% improvement in net loss, and a 49% improvement in adjusted EBITDA.
Hence, the funding measures complement these efforts and bolster the company’s cash position moving forward.
Not just that, this inflow of cash also builds upon significant technical momentum for ESS’ proprietary battery technology, including demonstration of extended duration of 12.2 hours at rated power and 17.8 hours at reduced power.
Founded in 2011, ESS’ rise up the ranks stems from leveraging earth-abundant iron, salt and water to deliver environmentally safe solutions capable of providing 10+ hours of flexible energy capacity for commercial and utility-scale energy storage applications. The company’s excellence in what it does can also be understood once you consider it empowers a host of project developers, independent power producers, utilities and other large energy users to deploy reliable, sustainable long-duration energy storage solutions.
“I am pleased to announce these transactions with our key partners coupled with a broader capital markets transaction that supports ongoing execution of our strategic pivot. This funding helps to strengthen our cash position to allow us to focus on the completion of key Energy Base contracting opportunities and to secure our broader capital raise,” said Kelly Goodman, Interim Chief Executive Officer at ESS.
