[Yonhap/ June 25, 2025] HD Korea Shipbuilding & Offshore Engineering (HD KSOE), in collaboration with HD Hyundai Heavy Industries, Donghwa Pneutec, the Korean Register (KR), and the Liberian Registry, has successfully completed the world’s first demonstration of a system that recycles boil-off gas (BOG) from LNG-fueled ships at berth into city gas.

The landmark demonstration was conducted at HD Hyundai Heavy Industries’ shipyard in Ulsan during the construction of a dual-fuel LNG-powered container ship. The initiative is part of a joint development project aimed at treating BOG during shipbuilding.

This technological breakthrough began in March when HD KSOE proposed repurposing BOG—gas that naturally vaporizes from LNG fuel during storage—into a usable city gas supply. Typically, this gas must be vented or burned off when ships are docked or under construction, as it cannot be used for propulsion.

To tackle this issue, HD Hyundai Heavy Industries and Donghwa Pneutec developed specialized BOG treatment systems, while KR and the Liberian Registry oversaw verification processes across design, manufacturing, and operation.

The problem arises as LNG stored in fuel tanks undergoes natural evaporation, increasing internal pressure. While this gas is usually harnessed as fuel when ships are at sea, current regulations and shore power requirements prevent its use while docked, resulting in wasteful emissions or combustion.

With the successful demonstration, the team has laid the groundwork for converting over 50 tons of BOG per ship into environmentally friendly city gas. This innovation aligns with global efforts to curb port emissions and complements the growing adoption of Alternative Maritime Power (AMP) systems.

Once fully commercialized, the system is expected to significantly enhance port sustainability and improve energy efficiency during ship construction.