Researchers have unveiled a strategy that can reduce emissions in the shipping sector by offsetting the random and unpredictable nature of weather conditions.
Erratic weather is a major threat to emissions reduction efforts in the shipping sector. It can be a cause of concern for ship owners installing modern sails that can reduce carbon emissions.
However, new research has highlighted operational strategies that can reduce shipping sector emissions by up to a quarter. This is set to strengthen confidence in sails as a decarbonisation tool.
The research, ‘Mitigating stochastic uncertainty from weather routing for ships with wind propulsion,’ is published in the journal Ocean Engineering.
The shipping sector contributes to 2-3% of global carbon emissions
It is estimated that the international shipping sector contributes to 2-3% of global carbon emissions annually.
Global urgent action is required: its target to cut carbon emissions by 50% relative to 2008 levels by 2050 falls short of the cuts required in the Paris Climate Agreement.
Combining modern sail technology with efficient routing systems is key
The team calculated carbon emissions from more than 1,000 ship departures setting sail from three main shipping routes.
They found that combining modern sail technology with efficient routing systems could provide greater assurances of carbon savings by using the technique that reduces uncertainty from unpredictable weather patterns.
Existing measures assume perfect foresight of future weather patterns
Dr James Mason, previously a postdoctoral researcher and now a visiting academic at the Tyndall Centre for Climate Change Research at The University of Manchester, said: “Current measures to reduce carbon emissions include fitting retrofit technologies, such as wind propulsion technology, where modern sails produce direct energy from the wind to reduce the power consumed by a ship’s engine.
“Weather routing is also used as an efficient routing system to allow a ship to deviate from standard shipping routes to search for new routes with more favourable winds.
“Current academic methods assume a perfect foresight of future weather rather than accounting for unpredictable winds that are happening in real-time. This can detrimentally reduce the carbon savings from weather routing and could present a real challenge for the shipping sector when trying to meet its climate reduction goals.”
Dr Alejandro Gallego Schmid, a Senior Lecturer at the Tyndall Centre for Climate Change Research, added: “This research provides an insight into which routes are most sensitive to changing weather forecasts when using wind propulsion and assesses a strategy that could help to mitigate the detrimental impact that unpredictable weather conditions can have.”
The new strategy reduced weather uncertainty
The new strategy mirrors existing routing methods in the sector by updating weather and wind every 12 hours to allow ships to adjust their routes based on the most accurate weather forecast available.
They tested the strategy by simulating 1,080 ship departures across eastbound and westbound journeys in the North Sea, South Atlantic Ocean, and North Atlantic Ocean. These journeys have voyage times of up to 12 days.
It was found that the method successfully reduced the uncertainty from unpredictable weather. From this, shipping sector emissions can be reduced by up to 25%.
More research is needed to understand how shipping sector emissions can be efficiently reduced
Although the new method reduces the uncertainty from unpredictable weather, it does not remove it entirely.
Wind propulsion and efficient routing can provide maximum carbon savings of up to 29% in ideal conditions. Weather uncertainty then reduces these savings by 10-20%.
More research is needed to understand how ships can achieve these maximum savings in practice.
Reducing shipping sector emissions by around a quarter by using wind propulsion with efficient routing could provide benefits for the sector.
The research offers an understanding of the potential carbon savings achievable through wind propulsion decarbonisation strategies. Without these, the goals set at the Paris Climate Agreement could be missed.
