Japan Engine Corporation (J-ENG) has renewed its licence agreement with Akasaka Diesels Limited, extending the company’s rights to manufacture and sell ammonia-fuelled marine engines alongside conventional heavy fuel oil engines.

Under the updated agreement, Akasaka receives a licence to produce and market J-ENG’s LSJA series ammonia-fuelled engines. J-ENG said development of the LSJA series was completed in 2025. The licence applies to the UE engine range, a series of domestically produced low-speed two-stroke engines in Japan.

Akasaka has long been a licensee for UE engines and has manufactured and sold the engines under agreement with J-ENG for several years.

J-ENG said it is also advancing the development of other alternative-fuel engine technologies. The company is currently working on hydrogen-fuelled engines in the LSGH series and has begun development of methanol-fuelled engines in the LSJM series, although no timeline for completion was provided.

According to the company, it plans to expand cooperation with its global network of UE engine licensees, referred to as the “UE family,” by providing licenses for next-generation engines designed to run on alternative fuels.