By the Numbers

Solutions for Slashing Greenhouse Gas Emissions

Examining the potential of various emissions reduction approaches

© OlegD / Adobe Stock
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When it comes to CO2 emissions reduction, the maritime industry has options. But how effective are they?

 In 2017, researchers took a close look at results from more than 150 studies on a wide array of emissions reduction approaches, from technical possibilities such as streamlined hull designs and alternative fuel and power sources, to operational measures such as voyage optimization. Their aim: measure the extent to which each of these options can help owners and operators reduce emissions output from their vessels.

The study quantified the emission reductions reported as achievable through each selected approach, and the results (shown below) were quite interesting.

The colored rectangular bars indicate the range of "typical" emissions reduction potential based on all the data points, while the horizonal black lines show the full range of potential carbon emissions reduction for the selected measure based on data from the studies that were reviewed. The small circles are the data points taken from each of the individual studies.

The Vanderbilt University Climate Change Initiative, which earlier this year prepared a report on the maritime industry's pathways to net-zero for the Blue Sky Maritime Coalition, observed substantial "lack of agreement" regarding the benefits of approaches toward greenhouse gas emissions reduction. "For example, it is commonly reported that speed reduction (or ‘slow steaming') always results in substantial emission reduction,' their report said. "But . . . the benefits of speed optimization (which apart from slow-steaming, takes further parameters into account, such as commercial obligations or port congestion) range from near nothing to 80%."

"While it is clear the approaches identified are likely to be well worth the investment on some vessels, the move towards digitalization can improve the industry's understanding of where particular approaches are most likely to be beneficial," the report said.


July 2023