Hyliion Achieves Major Milestone With Successful Emission Testing of KARNO™ Power Module

AUSTIN, Texas--(BUSINESS WIRE)--Hyliion Holdings Corp. (NYSE American: HYLN), a developer of sustainable electricity-producing technology, today announced the successful results of internal emissions testing of its KARNO™ Power Module, marking a critical step towards full commercialization of the company’s innovative distributed power solution.

The company’s internal testing confirmed that the KARNO Power Module can meet the stringent emissions requirements set by the South Coast Air Quality Management District (SCAQMD) Rule 1110.3, one of the most rigorous air-quality standards in the United States. Operating on pipeline natural gas, the system achieved less than 2.5 parts per million (PPM) of nitrogen oxides (NOx) and low single-digit PPM levels of carbon monoxide (CO)—far below the 12 PPM CO limit. These results were achieved without any aftertreatment system or catalyst and are corrected for 15% oxygen.

This emissions milestone builds on the U.S. Environmental Protection Agency’s (EPA) recent determination that the KARNO technology is not regulated as an internal combustion engine under existing federal law and regulations and therefore does not require federal approvals for deployment. While most power generation technologies are subject to both federal and local air district oversight, the KARNO technology will be governed solely by local air-quality standards, such as SCAQMD, due to its fundamentally different, ultra-low-emission design.

“This achievement validates the unique environmental performance benefits of our Power Module, representing a new era of clean, reliable, fuel-flexible power generation,” said Thomas Healy, Founder and CEO of Hyliion. “With these emissions results, we believe we’re well positioned as we work with customers and permitting agencies across the country to deploy our Power Modules.”

The KARNO Power Module leverages advanced thermodynamics and 3D metal additive manufacturing to generate electricity from heat, rather than traditional combustion. Its fuel-agnostic design enables operation on more than 20 different fuels—including natural gas, hydrogen, ammonia, renewable gases, and conventional liquids—supporting Hyliion’s mission to provide clean, adaptable power across a wide range of fuels and industries.

The successful internal emissions test reinforces Hyliion’s position at the forefront of clean distributed generation and strengthens the company’s pathway toward commercial deployments across data centers, industrial facilities, defense installations, and transportation infrastructure.

About Hyliion:

Hyliion is committed to creating innovative solutions that enable clean, flexible, and affordable electricity production. The Company’s primary focus is to provide modular power plant technology that can operate on various fuel sources to future-proof against an ever-changing energy economy. Headquartered in Austin, Texas, and with research and development in Cincinnati, Ohio, Hyliion is initially targeting the commercial and waste management industries with a locally deployable KARNO Power Module that can offer prime power as well as energy arbitrage opportunities. Beyond stationary power, Hyliion will address mobile applications such as vehicles and marine vessels. The Company aims to offer innovative, yet practical solutions that contribute positively to the environment in the energy economy. For further information, please visit www.hyliion.com.

Forward Looking Statements

The information in this press release includes “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. All statements, other than statements of present or historical fact included in this press release, regarding Hyliion and its future financial and operational performance, as well as its strategy, future operations, estimated financial position, estimated revenues, and losses, projected costs, prospects, plans and objectives of management are forward looking statements. When used in this press release, including any oral statements made in connection therewith, the words “could,” “should,” “will,” “may,” “believe,” “anticipate,” “intend,” “estimate,” “expect,” “project,” the negative of such terms and other similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain such identifying words. These forward-looking statements are based on management’s current expectations and assumptions about future events and are based on currently available information as to the outcome and timing of future events. Except as otherwise required by applicable law, Hyliion expressly disclaims any duty to update any forward-looking statements, all of which are expressly qualified by the statements herein, to reflect events or circumstances after the date of this press release. Hyliion cautions you that these forward-looking statements are subject to numerous risks and uncertainties, most of which are difficult to predict and many of which are beyond the control of Hyliion. These risks include, but are not limited to, our status as an early stage Company with a history of losses; our expectation of incurring significant expenses and continuing losses for the foreseeable future; our ability to develop key commercial relationships with suppliers and customers; our ability to retain the services of Thomas Healy, our Chief Executive Officer; the expected performance of the KARNO generator and system; the execution of the strategic shift from our powertrain business to our KARNO business, and the other risks and uncertainties described under the heading “Risk Factors” in our SEC filings including in our Annual Report (See item 1A. Risk Factors) on Form 10-K filed with the Securities and Exchange Commission (the “SEC”) on February 25, 2025 for the year ended December 31, 2024. Given these risks and uncertainties, readers are cautioned not to place undue reliance on such forward-looking statements. Should one or more of the risks or uncertainties described in this press release occur, or should underlying assumptions prove incorrect, actual results and plans could differ materially from those expressed in any forward-looking statements. Additional information concerning these and other factors that may impact Hyliion’s operations and projections can be found in its filings with the SEC. Hyliion’s SEC Filings are available publicly on the SEC’s website at www.sec.gov, and readers are urged to carefully review and consider the various disclosures made in such filings.