Jeff Loebbaka Joins ESS as Chief Commercial Officer

to Drive Growth and Maximize Customer Value

Expanded leadership team will grow ESS presence in global energy storage markets to catalyze the clean energy future

WILSONVILLE, Ore.–(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 the expansion of its executive leadership team.

Jeff Loebbaka has been named Chief Commercial Officer, adding significant depth to ESS leadership as the company continues to grow its global footprint and deliver long-duration energy storage solutions to customers worldwide.

“Jeff brings a wealth of experience growing emerging clean technology companies into global enterprises,” said Eric Dresselhuys, CEO of ESS. “His strategic vision will expand ESS’ capabilities to deliver long-duration energy storage solutions to global markets and catalyze the clean energy future.”

Loebbaka has held a number of executive leadership positions in technology and clean energy companies including AMP Robotics, Spruce Financial and Enphase Energy. He holds a B.S. in mechanical engineering from the University of Illinois Urbana-Champaign and an M.B.A. from the Kellogg School at Northwestern University.

“It is now clear that long-duration energy storage is foundational to a decarbonized energy system. ESS has the right technology and right team to meet skyrocketing demand for this critical solution,” said Loebbaka. “I am excited to join ESS during this period of growth and to enable the business to scale rapidly as I have throughout my career with companies at the forefront of the clean energy transition.”

About ESS

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.

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. 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.

Contacts

Investors:

Erik Bylin

Investors@essinc.com

Media:

Morgan Pitts

503.568.0755

morgan.pitts@essinc.com