HYLN · Hyliion Holdings Corp.

Hyliion Holdings Corp. (NYSE American: HYLN) (“Hyliion”), a developer of sustainable, electricity-producing technologies, today announced the successful completion of the first phase of extensive performance testing evaluating the KARNO™ technology on a representative U.S. Navy load profile. This marks a significant milestone in demonstrating the system’s load-following capability, reliability, and endurance as part of a development program funded by the Office of Naval Research (ONR) to advance the KARNO technology for deployment aboard U.S. Navy vessels and in stationary power applications. The KARNO system operated successfully through a demanding, mission-representative Navy load profile, demonstrating the system’s ability to manage rapid load changes and sustain performance under high-stress, real-world conditions. Through exposure to these dynamic load transitions, Hyliion showcased that the integrated system performs reliably under varying thermal, control, and operating