DNV Americas regional manager, Craig Koehne, discusses the measures that will yield substantial fuel and emissions savings during the transition to expensive carbon-neutral fuels
“Maritime decarbonisation is like a two-sided coin,” explains DNV Maritime Americas regional manager, Craig Koehne. One side of that coin is carbon-neutral fuels. “The ultimate decarbonisation of our industry is through alternative fuels,” says Mr Koehne, “and we will get to that point.”
But as Mr Koehne and the industry well know, that point is years away. The lack of availability is a major sticking point for alternative marine fuel options. Production volumes of carbon-neutral fuels are low and there is a lack of bunkering facilities for such fuels in ports.
“But that doesn’t mean we should not do anything between now and then,” he quickly points out.
That is where the flip side of the coin comes in: energy efficiency. “The best fuel is the one you don’t burn,” he declares.
Speaking with us at CMA Shipping 2025 just prior to the outcome of IMO’s MEPC 83, Mr Koehne detailed some of the “low-hanging fruit”— operational and technical short-term measures —that are available now to ship operators that offer immediate incremental fuel savings and greenhouse gas (GHG) emissions reductions.
Among the quick wins he cites operational measures like speed reduction or using digitalisation to achieve route optimisation, and energy-saving technologies (ESTs) such as wind-assisted propulsion, air lubrication and specialised coatings.
“All of these can offer incremental savings that, when you combine them and you do it in the correct way, can lead to real fuel and emissions savings,” says Mr Koehne, suggesting possible gains of as much as 16% in energy efficiency.
“The best fuel is the one you don’t burn”
Estimated fuel and emissions savings from various operational measures and ESTs have been revealed in numerous reports, studies, webinars and conferences by DNV. Ship operators need to carefully assess their decarbonisation investments and overall strategies based on technology readiness levels, vessel types, vessel age, trade routes, whether they will be designed in a newbuild or retrofit on an existing vessel, cost and return on investment.
Speed optimisation, for instance, can be applied to a broad range of vessels, with bulk carriers, container ships, pure car truck carriers and tankers among the biggest beneficiaries. Optimising a ship’s speed can involve general speed reduction or slow steaming, speed management during the voyage and applying just-in-time arrival.
