Four new liquefied natural gas (LNG)-powered car carriers are to be launched by Japanese shipping line Mitsui O.S.K. (MOL) as part of a push to add 90 such vessels to its fleet by 2030.

The push comes amid wider industry concerns about the suitability of LNG as an environmentally friendly fuel.

MOL plans four 7,000 unit capacity car carriers running on LNG as their main fuel, which will increase its total fleet capacity (including across its consolidated subsidiaries) to 735 vessels.

With a target of a 40% reduction in carbon intensity across the global fleet compared to 2008 levels set by the International Maritime Organisation (IMO), LNG is seen as a method of helping the industry meet this goal.

Despite this, the fuel is not without its critics; with some sources claiming that LNG is only of use as an interim fuel, considering IMO goals which aim for a greenhouse gas emission reduction of 50% by 2050.