Shipping and the Environment

There is an ever increasing pressure to reduce the carbon footprint so what is Maritime Transport doing for it's contribution?


A relentless global population increase is directly proportional to the continued growth in shipping over the past 100 years. Shipping can make a significant contribution to the global carbon reduction target and the Paris agreement temperature goals.  But maritime needs to accelerate change if it is to avoid being driven by punitive regulation.  IMO MEPC 72 set the 2050 target of a 50% reduction in carbon emissions compared to 2008 levels was the visionary target set, we have just had MEPC 74 and progress seemed a little slow even around short term measures. If speed optimisation or reduction becomes mandatory then an exemption for IGF code vessels including those using LNG would certainly encourage development, something the IMO is aware it needs to do.

Maritime Transport has developed extremely sophisticated fuel handling and propulsion machinery over the last 50 years that is capable of utilising essentially what is left from the refining process of crude oil. Until very recently Maritime Regulators have been focusing on reducing the residual high sulphur remaining in HFO which is of course expensive to remove.  Continued use of these fuels produces GHG's (CO2, N20) as well as local pollutants (SOX,NOX and particulates).  Use of high sulphur heavy fuel oils is soon to diminish with the Global Sulphur cap for 2020 approching fast.  Burning sulphur and emitting SOX and high NOX to the atmosphere is no longer acceptable in many areas known as ECA’s and these are on the increase.  A low take-up of scrubbers on board ships to date, can perhaps be attributed to regulatory uncertainty surrounding thier use.  Burning HFO and then scrubbing the exhaust gas and disposing of the waste to the sea or ashore is problematic and or expensive, it is however a short term solution that is likely to be regulated if not prohibited in the future.

For a new ship however the energy choices are becoming much clearer and will continue to do so.  Burning gas as we know is far cleaner than residual fuel oils and still cleaner than the more (expensive to produce) distillate fuels - yet by how much are the pollutants reduced?  Global fleet use of natural gas overnight would give 15% CO2 reduction alone, and in particular further efforts to reduce well to tank methane emissions upstream would bring that benefit nearer to 28% for slow speed 2 stroke engines.  Such a significant change in the maritime world takes time yet as the momentum builds towards cleaner fuels gas will no doubt have a significant part to play but just how much remains to be seen.   It is likely that there will be generation of change before we see a significant shift yet it is already happening in the passenger and container sectors for shipping.  One thing is certain in that maritime simply cannot meet 2050 targets without the extensive use of cleaner fuels, the principal one being LNG.

In the meantime, just how good is gas and what is the science that backs up the facts as the industry makes a step change as it did from sail to steam to oil and now to gas.  SGMF jointly commisioning a study in 2018 to answer the question once and for all for gas and this will be available now.

All other factors aside – a switch to gas is a clear tangible step in the right direction, but it is not a complete solution more of a commitment to reduce emissions and catch up with other sectors such as road transport and power generation.  Cars can leapfrog fuels and jump to electric, utilities can go renewable and nuclear but ships have to continue to carry fuel with them.  There is no doubt maritime can do its part in helping to combat climate change by making this change, a transition fuel perhaps but more likely a destination fuel until we solve the hydrogen solution for shipping.