A coalition of environmental groups has called on marine engine manufacturers to disclose the full extent of emissions from ships using LNG and ammonia as fuel.
Driven by market sentiment and regulations, ship owners are looking for options to replace conventionally powered vessels with more environmentally friendly vessels. LNG dual-fuel propulsion is one of the main options and the largest in the existing fleet. LNG is growing in popularity, accounting for 25% of container ship orders and 44% of cruise ship orders, according to Clarksons.
However, environmental groups argue in the letter that it is difficult to fully assess the impact of LNG-fueled ships because engine manufacturers do not fully disclose methane slip.
“Shipping companies are buying LNG-fueled ships as a way to clean up their fleets. But the amount of methane leaking from the engines remains unknown, making it difficult to actually know the true impact LNG has on the climate. There are no people. Engine manufacturers need to work on improving transparency,” said Constance Dijkstra, an LNG activist with a Brussels-based transport and environmental organization. Other organizations signed on to the letter include the Marine Conservation Fund, the Environmental Defense Fund and the Royal Belgian Institute of Natural Sciences.
Methane is a very potent greenhouse gas and, if released in significant quantities, could negate the claimed CO2 reduction benefits associated with LNG. To determine the extent of the problem, the coalition will issue detailed data to marine engine manufacturers on methane emissions from LNG-fueled engines for different engine designs (4-stroke vs. 2-stroke, high-pressure vs. high-pressure injection). requested that it be done. (e.g. low pressure) methane slip profiles are different.
The group raised similar questions about ammonia-powered engines, which are just beginning to emerge from development and testing. The first commercially available ammonia-fueled engine debuted last year, but there are currently few installations from which operational data can be collected. Still, NGOs want more information about nitrous oxide (N2O) and ammonia (NH3) emissions from these engines. That's because both are pollutants and nitrous oxide is a powerful greenhouse gas.