Energy-efficiency measures remain among the most immediate and practical options available to shipowners seeking to reduce greenhouse gas emissions as uncertainty continues over global regulations and the availability of low-GHG fuels, according to DNV’s 2026 Maritime Forecast to 2050.

The report examines four possible regulatory scenarios surrounding the International Maritime Organization’s Net-Zero Framework, ranging from adoption of the current framework to its rejection and prolonged regulatory uncertainty. DNV said these different outcomes could significantly affect fuel demand, energy-efficiency investments and long-term fleet strategies.

DNV identified energy efficiency as one of the most practical measures available regardless of the regulatory outcome. A case study involving hydrodynamic retrofits on a 5,000-TEU containership showed potential annual fuel savings of 16%, with an estimated payback period of around one to four years depending on future fuel prices.

The Maritime Executive reported that measures such as hydrodynamic improvements, wind-assisted propulsion, engine derating and speed reduction could help owners lower fuel consumption and emissions. According to the report, efficiency measures and speed reduction could contribute significantly toward shipping\'s emissions-reduction targets while also lowering annual bunker costs.

DNV also projects shipping demand for low-GHG fuels at between 4 and 22 million tonnes of oil equivalent by 2030 and between 33 and 185 million tonnes by 2050, depending largely on future regulations. The classification society said shipowners should consider strategies that provide benefits today while maintaining flexibility as regulations, fuel prices, technologies and fuel availability continue to develop.