World's largest ethane carrier in the works

China State Shipbuilding Corp is constructing the world's largest ethane transport ship, with delivery to the user expected in spring next year, according to its chief designer.

"The world's first 150,000-cubicmeter ultra-large ethane carrier, or ULEC, is being built by Jiangnan Shipyard. It has reached a major construction milestone: its hull sections have been completed and the vessel entered dry dock earlier this week," Zheng Shuangyan, a senior engineer at the Shanghai-based shipyard and chief designer of the ULEC model, told China Daily in an exclusive interview on Thursday.

The vessel is expected to be floated out in about a month and a half to begin outfitting, followed by a sea trial in January. If all goes smoothly, it will be delivered to the owner in February, said Zheng.

The first ULEC is part of an order for six vessels placed by Singapore-based Eastern Pacific Shipping with Jiangnan Shipyard, a subsidiary of China State Shipbuilding Corp, in August 2024.

With a cargo capacity of 150,000 cu m each, the vessels will become the world's largest ethane carriers, establishing Jiangnan as the first shipyard worldwide to build such ships. Construction of the first vessel began in August 2025.

Independently designed by Jiangnan Shipyard, the ULEC model uses the Mark III membrane containment system developed by GTT, a French company specializing in cryogenic membrane containment systems for transporting and storing liquefied gases. Zheng said that the vessel can carry ethane, ethylene and liquefied petroleum gas, providing maximum cargo flexibility throughout its operational life.

She added that engineers had used computational fluid dynamics and model tank tests to optimize the hydrodynamic performance of the hull and cargo tanks, thus adapting the vessel to typical transpacific and transatlantic routes and ethane trading patterns. Jiangnan also independently completed the tank design and the insulation panel layout for the Mark III containment system.

"All of these meticulous designs will ensure users outstanding profitability," the chief designer said.

ULEC's overall design draws on Jiangnan's experience with very large ethane carriers currently under construction and membrane containment systems used in liquefied natural gas carriers, she said.

Ethane, a hydrocarbon found in oil and gas fields, is an important raw material for the petrochemical industry and is used to make numerous everyday products. When cooled to minus 88 C, it changes from a gas to a liquid, significantly reducing its volume and making it suitable for bulk transportation as liquefied ethane gas.

As the ethane market matures, demand for larger capacity vessels to transport ethane across oceans has grown, with shipowners increasingly favoring larger vessels over smaller ones.

Eastern Pacific Shipping is one of the world's largest privately owned ship management companies, with a 60-year history. It manages a diversified fleet of more than 270 vessels and has more than 6,000 sea and shore staff.

In 2023, EPS partnered with Jiangnan for the first time to order six of the world's biggest very large ammonia carriers.