ICCT policy brief explores benefits of global 0.10% sulphur cap on marine fuels

The International Council on Clean Transportation (ICCT) on Tuesday (8 July) introduced a policy brief examining how further reducing the global maximum allowable fuel sulphur content of bunker fuel from 0.5% to 0.1% could affect air pollution emissions and premature mortality from fine particulate matter (PM2.5).

Currently, ships must adhere to a global 0.5% fuel sulphur limit and a 0.1% limit in ECAs, unless they use scrubbers. However, studies have found that ships using scrubbers with heavy fuel oil emit more particulate matter and black carbon emissions than those using marine gas oil.

The brief considered three compliance pathways:

1. Scrubber Max scenario in which ships that use very-low sulfur fuel oil (VLSFO) switch to high-sulfur heavy fuel oil (HFO) with scrubbers to comply;
2. Scrubber Allowed scenario in which ships that use VLSFO switch to marine gas oil (MGO) to comply;
3. Distillate Only scenario in which scrubbers are not allowed and ships that use HFO and scrubbers or VLSFO switch to MGO to comply.

In summary, the research found that relative to a baseline scenario based on 2023 ship activity data, reducing the sulphur content of marine fuels to comply with a 0.1% sulphur limit would:

• Mitigate air pollution. Across the three compliance scenarios, shipping-attributable sulfur oxide emissions are estimated to fall by 75%–85%, PM2.5 by 46%–66%, and black carbon by 27%–41%. The scenario prohibiting scrubbers yields the highest estimated emission reductions.
• Reduce premature deaths. The three compliance scenarios avoid between 3,900 and 4,500 premature deaths annually, with the most significant reductions achieved when scrubbers are not allowed.
• Deliver substantial economic benefits. Health-related economic benefits are estimated to range from $9.3 billion to $10.9 billion annually, depending on the compliance pathway.
• Incentivize cleaner fuels. A global 0.1% sulfur standard that promotes distillate fuel use would increase baseline fossil fuel costs and reduce the price gap between conventional and zero or near-zero greenhouse gas emission fuels.

The complete policy brief Health and air pollution benefits of a global 0.1% fuel sulfur limit  on marine fuels can be obtained from the link here.

Photo credit: International Council on Clean Transportation
Published: 9 July 2025