Veteran Energy Storage Commercial Leader to Drive Global Commercial Execution as ESS Strengthens Leadership Team and Scales Deployments

ESS Tech, Inc. (NYSE:GWH) ("ESS" or the "Company"), a leading innovator in long-duration energy storage solutions, today announced that Randall "Randy" Selesky has joined the company as Chief Commercial Officer (CCO). In this role, Selesky will lead global commercial strategy, sales, marketing, product management, and business development initiatives as ESS advances commercialization and scales deployment of its long-duration energy storage solutions worldwide.

Selesky joins ESS with more than 20 years of leadership in the energy sector, including more than a decade in the battery storage industry. Prior to joining ESS, he served as the Chief Commercial Officer at VoltStorage, where he played a central role in shaping commercial strategy, building partnerships, and guiding the company's market expansion. Throughout his career, Selesky has been recognized for his ability to transform commercial organizations, build high-performing teams, and accelerate the adoption of innovative clean-energy technologies. His background encompasses large-scale market development, enterprise-level sales, and driving revenue growth in rapidly evolving segments of the energy transition.

This appointment builds on Essays recent leadership transformation designed to strengthen governance, execution, and financial discipline, with an emphasis on capital allocation and accountability. At ESS, Selesky will spearhead commercial execution as global demand for long-duration energy storage (LIES) continues to rise. His expertise positions the company to expand its market presence and meet the growing need for long-duration assets capable of improving grid reliability, enabling deeper renewable integration, and supporting the shift toward a decarbonized energy system.

"Randy is a proven commercial leader with extensive experience in the energy and battery storage industries, building high-performing teams, and converting market demand into durable revenue," said CEO Drew Buckley. "His leadership will be instrumental as we sharpen execution and deliver high-performing, market-ready solutions to customers seeking reliable long-duration storage."

Mr. Selesky added, "I am excited to join ESS at an important moment for the Company and for the broader energy industry. Long-duration storage is becoming essential for the next phase of the energy transition, and ESS is uniquely positioned with a safe, sustainable solution and a strong foundation to accelerate commercial momentum ready to meet the market's needs. I look forward to helping scale customer adoption globally."

About ESS Tech, Inc.

ESS (NYSE:GWH) is the leading manufacturer of long-duration iron flow energy storage solutions. ESS was established in 2011 with a mission to accelerate decarbonization safely and sustainably through longer lasting energy storage. Using easy-to-source iron, salt, and water, ESS iron flow technology enables energy security, reliability and resilience. We build flexible storage solutions that allow our customers to meet increasing energy demand without power disruptions and maximize the value potential of excess energy. For more information visit www.essinc.com.

Forward-Looking Statements

This communication contains certain forward-looking statements, including statements regarding ESS and its management team's expectations, hopes, beliefs, intentions or strategies regarding the future. The words "anticipate," "believe," "continue," "could," "estimate," "expect," "intends," "may," "might," "plan," "possible," "potential," "predict," "project," "should," "will," "would" and similar expressions may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. Examples of forward-looking statements include, among others, statements regarding the Company's employees, commercial expectations regarding sales order and pipeline, the expected integration of the VoltStorage intellectual property and technology, ESS product development and manufacturing, and relationships with customers. These forward-looking statements are based on ESS' current expectations and beliefs concerning future developments and their potential effects on ESS. Many factors could cause actual future events to differ materially from the forward-looking statements in this communication. There can be no assurance that the future developments affecting ESS will be those that we have anticipated. These forward-looking statements involve a number of risks, uncertainties (some of which are beyond ESS control) or other assumptions that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements, which include, but are not limited to, general economic and market conditions as well as geopolitical developments and other risks and uncertainties described more fully in the section titled "Risk Factors" in the Company's Quarterly Report on Form 10-Q filed on November 13, 2025, and the Company's other filings with the U.S. Securities and Exchange Commission. Except as required by law, ESS is not undertaking any obligation to update or revise any forward-looking statements whether as a result of new information, future events or otherwise.

View source version on businesswire.com: https://www.businesswire.com/news/home/20260219454311/en/

Company

investors@essinc.com

Investor Relations

Chris Tyson

Executive Vice President

MZ Group – MZ North America

Phone: (949) 491-8235

GWH@mzgroup.us

www.mzgroup.us

ESS Appoints Randall Selesky as Chief Commercial Officer to Accelerate Global Growth