The ultimate goal of zero greenhouse gas emissions can only be delivered with “genuine zero CO2 fuels” as the greater use of LNG and biofuels is likely to present only an interim solution to meeting the International Maritime Organization’s emissions reduction target, the International Chamber of Shipping said.
In April, a key committee of the IMO agreed to an initial strategy of cutting the shipping industry’s total GHG emissions by at least 50% from 2008 levels by 2050. In addition the, IMO has also set a goal of improving the sector’s efficiency by at least 40% by 2030 and by 70% by 2050.
The ICS report released Monday comes ahead of a key IMO meeting scheduled for October which is expected to include discussions around a list of possible candidate measures for CO2 reduction.
Zero CO2 fuels include using radical and as yet unproven technologies such as hydrogen fuel cells using ammonia or methanol, or batteries powered by renewable energy, ICS said.
Although currently only suitable for ships on short voyages, there is potential to apply battery hybrid technologies widely used in the automotive sector, ICS said.
“In the longer term, there seems to be a genuine potential to utilize batteries as the primary source of power even for larger ships. Such batteries would probably be extremely large, but with appropriate adjustments to the ship the loss of cargo capacity could be offset by eliminating fuel tanks and conventional engine machinery,” it said.
Significant research is also underway to develop energy-efficient processes for producing hydrogen from water using thermochemical processes.
Hydrogen has a lower energy density than conventional fossil fuels and would need careful risk management, ICS said. It has a very wide flammable range and very low minimum ignition energy, while embrittlement of metals might lead to leakages.
However, hydrogen could be reformed on board ship from almost any feedstock in order to ease fuel storage and handling and to minimize the safety risk, ICS said.
The principal concern over using ammonia as a bunker fuel is safety. Some types of fuel cell stack are incompatible with ammonia, so that even very small quantities of ammonia remaining after reforming into hydrogen could seriously affect performance.
“Nevertheless, as with battery technologies, the challenges involved might not be insurmountable,” the ICS said.
In addition, nuclear fuels could be readily applied to many merchant ships to eliminate CO2 emissions completely, ICS said.
“Only a small nuclear reactor would be required, with a life of many years, removing the need for ships to refuel or carry bunkers,” ICS said, adding that Russia already successfully operates a number of nuclear ice breaking vessels in the Arctic.
ICS also said it was “strongly opposed” to the concept of IMO establishing a mandatory system of operational efficiency indexing for application to individual ships as a possible candidate measure for CO2 reduction as it would lead to serious market distortion.
CO2-efficient ships are correctly rewarded by the market because their lower fuel costs make them commercially more competitive, it said.
The ultimate purpose of operational efficiency indexing is, however, is to penalize individual vessels twice, on the basis of a theoretical and arbitrary operational rating that has little relation to the actual CO2 emissions of the ship in real life, ICS said.
“We now expect discussions at IMO to begin in earnest on the development of additional CO2 reduction measures, including those to be implemented before 2023. ICS will continue to participate constructively,” ICS chairman Esben Poulsson said.
Source: PlattsPrevious Next