In line with the Paris Agreement, the shipping industry is constantly looking to technology for ways to reduce its share of greenhouse gas emissions. Significant cuts in emissions however can be challenging to achieve unless fundamental changes are realised in the short term.
Numerous Options Currently on the Table
Industry Leaders such as MAERSK and academic groups such as the Low Carbon Shipping Consortium have been investigating new technologies and operational improvements to rapidly reduce emissions. According to the Journal of Carbon Management, here are five viable options, not necessarily mutually exclusive, that would help the shipping industry reduce emissions.
- Utilization of Renewable Energy Sources - The use of wind power for propulsion. Sails, kite systems and flettner rotors can be installed or retrofitted on ships for supplemental, auxillary power.
- Switching to Less Carbon-Intensive Fuels - Liquified natural gas (LNG), biogas, biofuels and even nuclear can provide lower carbon alternatives, however each have potential downsides that must be mitigated.
- Energy Storage and the Use of Fuel Cells - The use of batteries and cold ironing (using shoreside electrical power to a ship at berth) could enable the industry to decarbonise by running off of low-carbon produced electricity from the grid.
- Changes in Operations - Route optimisation and operating at slower speeds (slow steaming) can reduce fuel consumption considerably.
- Smaller Incremental Measures - Mostly driven by technology, with limited sector disruption. Improvements such as hull design, propeller optimisation and waste heat recovery should be able to reduce emissions by as much as 5%.
Fuel Choice is Critical
Regulation surrounding pollution and ongoing efforts at Marine Environment Protection Committee (MEPC) to introduce more stringent measures on climate change will drive down the future use of heavy fuel oil. Additionally, discussions on the reduction of sulphur limits in shipping fuels, means that diesel and LNG might not be viable despite LNG being considered as the most viable fuel alternative within the industry. There are numerous fuels still to consider, hydrogen (with and without carbon capture and storage), renewable hydrogen, methanol, straight vegetable oil, biodiesel and bio-LNG.
The true impact of a fuel choice should consider the environmental implications of the full life cycle, not just combustion, of the fuel including manufacturing, distribution, use and disposal. Failing to consider these wider impacts does not take into consideration the true emissions impact of any alternative fuels. Whichever fuel choice the industry adopts, it should rely on the decarbonisation of the energy input required for fuel production to ensure it can deliver absolute reductions in greenhouse gas emissions.
Looking ahead, as the shipping industry works to deliver reductions in its share of greenhouse gas emissions, contributions from technology, regulation driven changes, and imoprovements from within the industry will all help to contribute to their success.