LR: LNG Advantages Not as Clear-Cut as Some Suggest

Bradshaw writes that considering fuels' entire life-cycles could change their image

Liquefied natural gas (LNG) has a strong future as a marine fuel, but its environmental and economic benefits are not as clear cut as sometimes suggested, John Bradshaw, Lloyd's Register (LR) Marine's lead project engineer for machinery writes.

So far, only a few LNG-fuelled ships are being ordered, and the fuel is unlikely to grow greatly in popularity until a fuel supply infrastructure is in place, particularly outside North America, where natural gas is unusually inexpensive.

LNG and other alternative fuels, including methanol, have been adopted by ferry operators in Emissions Control Areas (ECAs) in particular, but in other shipping sectors they have generally been deemed too expensive.

"Society wants unlimited, cheap and clean energy," Bradshaw writes.

"We have yet to find a fuel satisfying all three demands and are unlikely to reach this energy nirvana soon."

Eventually, demand for bunkers could be satisfied with synthesised fuels, or new technologies could provide ways around concerns about carbon dioxide (CO2) emissions.

Brandshaw also suggests that the environmental benefits of LNG may be less obvious if the entire life-cycle of each fuel is considered, given that bunker fuel is essentially a waste product of oil refineries and that emissions from vessels burning heavy fuel oil (HFO) can be cleaned with scrubber systems.

"The marine Energy Efficiency Design Index (EEDI) carbon factors are based on stack emissions, but society increasingly expects a more holistic view, considering extraction, refining and supply," Bradshaw writes.

"This could fundamentally change the carbon intensity of marine fuels."

Some industry players have said they expect LNG to gain much wider adoption as the construction of infrastructure for the fuel moves forward.