ESS Tech Raises Capital Amid Leadership Changes

Introduction

ESS Tech Inc. (NYSE: GWH) is a manufacturer of long-duration energy storage systems based in Wilsonville, Oregon, specializing in iron flow technology. Founded in 2011, the company focuses on providing solutions that capture excess renewable energy generation and discharge it for up to 22 hours, addressing demand from AI data centers and goals for decarbonization. As of July 2, 2025, its share price was USD 1.5491, representing an increase of 17.36% for the day, with 164,169 shares traded.

Corporate Structure and Workforce

ESS Tech employs between 201 and 500 staff, including engineers, materials scientists, and product specialists. The leadership team includes Kelly Goodman as interim CEO, Tony Rabb as CFO, and Ben Hang as EVP of Engineering, following the resignation of former CEO Eric Dresselhuys in February 2025.

Energy storage by NASA

Recent Developments and News

In February 2025, Eric Dresselhuys resigned as CEO and board member. An interim leadership office was established to explore strategic transactions and to reposition the company for longer-duration projects of 12 to 24 hours targeting AI and data center loads.
On June 3, 2025, ESS announced it had raised unexpected capital to prevent a temporary shutdown of its Oregon manufacturing facility. The company plans to implement cost-management measures and focus on its gigawatt-scale Energy Base solution while fulfilling existing orders for four Energy Warehouses.
On May 30, 2025, ESS filed a Conflict Minerals Report (Form SD) for the year ending December 31, 2024, as part of its commitment to supply-chain transparency and regulatory compliance.

Financial and Strategic Analysis

As of mid-2025, ESS Tech’s market capitalization was approximately USD 12.95 million. Its trailing twelve-month revenue was USD 4.16 million with a net loss of USD 85.94 million, reflecting ongoing research and development and deployment costs. The balance sheet indicated USD 12.8 million in cash and a debt-to-equity ratio of 10.7%. Valuation metrics include a price-to-sales ratio of 3.06 and a price-to-book ratio of 1.07.
The company’s technology is designed for a 25-year lifespan with zero capacity fade, utilizing iron, salt, and water. In April 2025, the Export-Import Bank of the United States provided funding of USD 50 million for a manufacturing expansion under the Make More in America Initiative. ESS has also received IEEE 693 seismic certification for its Energy Center product and holds multiple UL certifications.

Market Position and Industry Context

The global energy grid is projected to require an estimated 8 TW of long-duration energy storage by 2040 to meet clean energy targets. ESS Tech’s iron flow batteries compete with lithium-ion systems, which have experienced significant cost reductions, especially for durations below 12 hours. While the capital expenditures for flow batteries per kWh remain higher, ESS aims to create value through unlimited cycling, the modular decoupling of energy and power capacity with its Energy Base solution, and expedited deployments within the United States. Other publicly traded companies in the long-duration energy storage market include Eos Energy Enterprises and Energy Vault. The competitive landscape will continue to be influenced by technological advancements and policy incentives, such as production tax credits.

tl;dr

On February 21, 2025, ESS Tech’s CEO Eric Dresselhuys resigned, and an interim leadership office was formed. In early June 2025, the company raised significant capital to maintain operations at its Oregon plant and is transitioning from Energy Warehouse container systems to its gigawatt-scale Energy Base solution. Shares increased by 17.36% on July 2, 2025, amid these developments. ESS is also exploring strategic transactions to support long-duration projects for AI and data center markets while managing operating expenses.