Third IMO Greenhouse Gas Study 2014

142 Third IMO GHG Study 2014
Figure 85: Emissions projections for the BAU transport demand scenarios
Figure 86 analyses the impact of the fuel/ECA and efficiency scenarios. It shows for one transport demand
scenario (RCP8.5 SSP5, i.e. high economic growth and high fossil fuel use) the impact of different assumptions
on the other scenario parameters. The two lower projections assume an efficiency improvement of 60%
instead of 40% over 2012 fleet average levels in 2050. The first and third projections have a 25% share of LNG
in the fuel mix in 2050 instead of a share of 8%. Under these assumptions, improvements in efficiency have
a larger impact on emissions trajectories than changes in the fuel mix.
Figure 86: Output for demand scenarios under conditions of high LNG/extra ECA and high efficiency
Figure 87 shows the contribution of various ship types to the total emissions in one scenario. Unitized cargo
vessels (container and general cargo ships) are projected to show a rapid increase in number and in emissions.
In comparision, emissions from other ship types, such as dry bulk and liquid bulk carriers, grow at a lower rate
or decline as a result of improvements in efficiency and (in this case) limited growth of transport demand. While