A Norwegian research group recently stated that overall emissions of greenhouse gases would be lower if ships installed exhaust gas cleaning systems and continued to use heavy fuel oil than if they followed other routes to comply with looming IMO 2020.
The study by Sintef, released in June, concluded that higher total emissions result if ships instead switch to cleaner fuels – low-sulfur fuel oil, marine gas oil or natural gas – because those fuels require additional refining, which adds to greenhouse gas emissions.
IMO 2020 is focused on emissions of sulfur compounds. Scheduled to take effect Jan. 1, it will reduce the global cap on sulfur in marine fuels from 3.5 percent by weight to 0.5 percent by weight. The regulation prescribes four routes for ship operators to comply: by switching from heavy fuel oil to low-sulfur fuel oil, marine gas oil or natural gas; or by installing exhaust scrubbers, in which case ships may continue to run on heavy fuel oil, which is higher in sulfur.
Sintef, which is based in Trondheim, Norway, said producing heavy fuel oil generates lower amounts of carbon dioxide than the other fuels allowed under IMO 2020 because heavy fuel oil is a bottom-of-the-barrel product, meaning it is a by-product of making other petroleum products. Additional processing – and in some cases additional investment – is required to make low-sulfur fuel oil or marine gas oil.
IMO 2020 is expected to have significant impacts on the lubricant industry – partly because performance requirements of marine lubricants differ depending on the type of fuel used. In addition, analysts expect significant numbers of ships to switch from running on heavy fuel oil to low-sulfur fuel oil, marine gas oil or natural gas, reducing demand for heavy fuel oil and leading to the closing of some refineries that make heavy fuel oil. Those refineries tend to produce API Group I base stocks, so this trend would reinforce the global base oil supply shift from Group I to Group II and Group III base oils.