How good is LNG as a marine fuel regarding greenhouse gas emissions?—Review of recent studies from Europe and the U.S.

This paper will try to incorporate the aspects mentioned above into a more comprehensive Greenhouse Gas (GHG) analysis for marine fuels that meet the ECA regulations.

1.1 Fuel life cycle GHG emissions

The emissions of three main GHGs associated with marine fuel combustion are typically evaluated in the WtW analysis: CO2, CH4 and N2O. While N2O hasn’t much impact on the balance, CH4 does. The global warming potential of these gases varies i.e. 1 g of CH4 is equivalent to 25 g of CO2 and 1 g of N2O is equivalent to 298 g of CO2. Hence, in order to normalise these values a “CO2 equivalence” unit is employed (CO2eq).