Shipowners should prioritise energy-efficiency measures that can cut fuel use immediately as uncertainty over the IMO Net-Zero Framework complicates investment in low-GHG fuels, according to DNV.
The Norway-headquartered classification society reached the conclusion in the 10th edition of its Maritime Forecast to 2050.
DNV tested four regulatory scenarios, ranging from adoption of the IMO framework in its current form to rejection and prolonged regulatory gridlock.
Under stronger global regulation, the world fleet could consume as much as 25% less energy in 2050 than under a scenario dominated by regional emissions rules.
A DNV case study of a 5,000-TEU containership found hydrodynamic retrofits could cut annual fuel consumption by 16%, with an estimated payback period of about one to four years depending on fuel prices.
The outlook for low-GHG fuels is more uncertain. DNV estimates shipping demand at 4m to 22m tonnes of oil equivalent, or Mtoe, in 2030 and 33m to 185m Mtoe in 2050.
Projects under development could theoretically provide as much as 270m Mtoe by 2030, although DNV expects actual production to be significantly lower because of delays, cancellations and other uncertainties.
The cost of avoiding carbon dioxide emissions ranges from about $180 to $1,290 per tonne of CO2 across different fuel pathways.
“In the meantime, shipowners need strategies that deliver benefits today while remaining resilient across a range of regulatory and market outcomes,” interim DNV Maritime chief executive Cristina Saenz de Santa Maria said.
Lead report author Øyvind Sekkesæter said different regulatory outcomes could produce markedly different levels of efficiency investment, fuel demand and greenhouse-gas emissions.
The IMO approved the draft Net-Zero Framework at MEPC 83 in April 2025, but the extraordinary session convened for formal adoption was adjourned in October 2025. Further negotiations are scheduled ahead of MEPC 85 from 30 November to 3 December 2026, with the adjourned session due to resume on 4 December, subject to confirmation by MEPC 85.
DNV is an independent assurance and risk-management group headquartered in Oslo. Its maritime business employs about 3,500 people in more than 65 countries, while the wider group operates in more than 100 countries.