• Initial deployment under 2 GWh framework agreement supports SMUD 2030 Clean Energy Vision

WILSONVILLE, Ore. / Sep 11, 2023 / Business Wire / ESS Tech, Inc. (“ESS”) (NYSE: GWH), a leading manufacturer of long-duration energy storage systems (LDES) for commercial and utility-scale applications, today announced that it has completed commissioning of six Energy Warehouse™ systems delivered to the Sacramento Municipal Utility District (SMUD), the nation’s sixth-largest community-owned electric service provider.

The six Energy Warehouse™ systems represent the first delivery under a framework agreement first announced in September 2022. Under that agreement, ESS will deliver up to 200 megawatts (MW) / 2 gigawatt-hours (GWh) of iron flow LDES systems to SMUD. Once fully operational and paired with renewable energy, 2 GWh of iron flow battery systems are expected to enable the elimination of approximately 284,000 metric tons of CO2 emissions per year from SMUD’s system. With the arrival of the units, SMUD prepares for the next phases of integrating the system into its expansive clean power portfolio. Once operational, SMUD will also train staff on utility-scale applications and clean energy dispatch of long-duration battery systems.

ESS technology directly supports the utility’s ambitious 2030 Clean Energy Vision by enabling increased utilization of renewable energy, providing neighborhood resiliency, and promoting social justice and equity with safe and sustainable energy storage infrastructure and reduced emissions.

"SMUD is on a bold journey to eliminate all carbon emissions from our power supply by 2030 without compromising our world class reliability and rates that are consistently among the lowest in California,” said Paul Lau, CEO & General Manager of SMUD. “We’re excited to embrace cutting-edge technologies, including through our partnership with ESS, to deliver and grow long-duration energy storage. In addition to accelerating our transition to a clean energy future, this partnership and technology will spur economic development, equitable access to clean energy and a brighter future for the entire Sacramento region.”

With up to 12 hours of flexible energy capacity, ESS technology provides cost-effective, resilient and sustainable energy storage well-suited to multiple use cases including utility-scale renewable energy installations, solar + storage microgrids, grid load-shifting and peak shaving, and other ancillary grid services. ESS systems are safe and sustainable and can be deployed in populated areas without the risks associated with other storage technologies.

“The need to decarbonize our energy system and ensure resilient, reliable sources of energy becomes more apparent every day. SMUD’s leadership is setting an example for utilities worldwide to embrace energy storage for a clean, resilient and equitable energy future,” said Eric Dresselhuys, CEO of ESS. “The commissioning of these systems marks an important milestone in our partnership with SMUD. We look forward to delivering and commissioning additional long-duration energy storage systems to enable deep decarbonization and provide sustainable economic opportunity in the greater Sacramento region.”

In addition to deploying critical energy storage technology, ESS and SMUD plan to establish a Center of Excellence (COE) for energy storage manufacturing in Sacramento. The COE will be established in partnership with local educational institutions and will provide workforce training and support economic development in the greater Sacramento region.

About ESS, Inc.

At ESS (NYSE: GWH), our mission is to accelerate global decarbonization by providing safe, sustainable, long-duration energy storage that powers people, communities and businesses with clean, renewable energy anytime and anywhere it’s needed. As more renewable energy is added to the grid, long-duration energy storage is essential to providing the reliability and resiliency we need when the sun is not shining, and the wind is not blowing.

Our technology uses earth-abundant iron, salt and water to deliver environmentally safe solutions capable of providing up to 12 hours of flexible energy capacity for commercial and utility-scale energy storage applications. Established in 2011, ESS Inc. enables project developers, independent power producers, utilities and other large energy users to deploy reliable, sustainable long-duration energy storage solutions. For more information visit www.essinc.com.

About SMUD

As the nation’s sixth-largest, community-owned, not-for-profit electric service provider, SMUD has been providing low-cost, reliable electricity to Sacramento County for more than 75 years. SMUD is a recognized industry leader and award winner for its innovative energy efficiency programs, renewable power technologies and for its sustainable solutions for a healthier environment. Today, SMUD’s power supply is on average about 50 percent carbon free and SMUD has a goal to reach zero carbon in its electricity production by 2030. For more information on SMUD’s Zero Carbon Plan and its customer programs, visit smud.org.

Forward-Looking Statements

This communication contains certain forward-looking statements regarding ESS and its management team’s expectations, hopes, beliefs, or intentions regarding the future. The words “estimate”, “expect”, “will” 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 ability to execute on orders and the Company’s relationships with customers. These forward-looking statements are based on ESS' current expectations and beliefs concerning future developments. Many factors could cause actual future events to differ materially from such expectations, including, but not limited to, continuing supply chain issues; delays, disruptions, or quality control problems in the Company’s manufacturing operations; the Company’s ability to hire, train and retain an adequate number of manufacturing employees; issues related to customer acceptance of the Company’s products; as well as those risks and uncertainties set forth in the section entitled “Risk Factors” in the Company’s Quarterly Report on Form 10-Q for the six months ended June 30, 2023, filed with the Securities and Exchange Commission (the “SEC”) on August 8, 2023, and its other filings filed with the SEC. 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.