Middle Eastern liquefied natural gas (LNG) producer QatarEnergy has signed a contract with China State Shipbuilding Corporation (CSSC) for the construction of 18 supersize LNG carriers.

The newbuilds under the deal， which the Chinese shipbuilding conglomerate described as the world’s largest single shipbuilding order， will be delivered by Hudong-Zhonghua Shipbuilding.

The so-called Q-Max units will have a capacity of 271，000 cu m， making them the largest-ever ships ordered in this sector. Qatar already has 14 Q-Max vessels on a long-term charter with a carrying capacity of around 266，000 cu m supplying Far Eastern， European and various other markets.

Hudong-Zhonghua presented its design concept for the world’s largest LNG carrier last year， receiving approval in principle from many of the leading class societies. The record-breaking vessel could transport enough LNG to provide gas for 4.7m Shanghai homes for a month， 25-30% more efficiently than a 170，000 cu m vessel.

Qatar’s LNG shipbuilding programme is the largest of its kind in the history of this sector， with 104 conventional newbuilds already firmed up under long-term charter contracts with multiple shipowners. The ships will support Qatar’s expanded LNG production capacity from the country’s North Field and Golden Pass in the US while meeting long-term fleet replacement requirements.

Financial terms for the latest series of Q-Maxes have not been disclosed， but shipbuilding sources quote each vessel at around $330m. Shipowners in line， suggested by the industry sources， include Nakilat， which should take half of the orders， with the rest going to Chinese players.