Shipowners can cut energy use across the global fleet by up to 28% by 2050 through fleet renewal, operational improvements and retrofits — without waiting for a winning fuel, according to the 10th edition of DNV's Maritime Forecast to 2050.

The report lands at a moment of regulatory paralysis. The International Maritime Organization has delayed its decision on the Net-Zero Framework (NZF), the mechanism targeting net-zero greenhouse gas emissions by or around 2050, and that delay is prolonging uncertainty for every newbuilding decision in shipping.

DNV presents four scenarios for possible future regulatory development. The key implication cuts deeper than the scenarios themselves: prolonged uncertainty at the IMO raises the likelihood of additional regional regulations targeting international shipping. For Greek and Cypriot owners operating globally, that means planning for a patchwork, not a single rulebook.

What does the data show on alternative fuels?

The alternative-fuel fleet is expanding fast, though from a low base. Measured in gross tonnes, the share of alternative fuel-capable ships has increased more than 10-fold, from 0.4% in 2020 to 5.2% by August 2026, excluding LNG carriers.

The vessel count tells a similar story:

• Ships capable of using alternative fuels have grown more than six-fold, from 213 to 1,329 vessels (excluding LNG carriers).
• LNG dual-fuel remains the dominant fuel technology across segments.
• Methanol capability is gaining a substantial foothold, particularly in containerships.
• Ammonia and other options are emerging.
• Low-GHG fuel bunkering operations are now recorded at nearly 90 ports worldwide.

The variation across ship segments remains significant — a point with direct relevance to the Aegean and Eastern Mediterranean, where tanker and bulk carrier tonnage dominates orderbooks.

Why does efficiency come first for Greek and Cypriot owners?

Lefteris Koukoulopoulos, Regional Decarbonization Specialist for Southeast Europe at DNV Maritime, said the efficiency message stands out above all others in the report.

"Energy efficiency is the most immediate and practical decarbonization solution available to shipowners today," Koukoulopoulos said. "It offers shipowners a way to reduce fuel consumption and emissions today, while managing costs and keeping their options open for the future."

Importantly, he added, efficiency creates value regardless of which fuel pathway ultimately succeeds.

This reflects the conversations he is having in Greece and Cyprus. While most newbuilding orders — particularly in the tanker and bulk carrier segments — are still conventionally fuelled, owners are examining how to integrate as many energy-efficient options as possible into new designs.

"It is a practical and flexible approach: improve performance today, while retaining the ability to respond as regulations, technologies and fuel markets evolve," Koukoulopoulos said.

The numbers back the strategy. Energy-efficiency measures and speed reductions can reduce energy use across the world fleet by up to 16% in 2030 compared with business-as-usual. The potential toward 2050 is larger still. Efficiency also lowers the cost of operating on more expensive low-GHG fuels once the transition accelerates — a double dividend for owners holding fuel-option flexibility.

What happens after efficiency runs its course?

DNV is explicit: full maritime decarbonization will require a shift from fossil fuels to low-GHG fuels, complemented by other solutions such as onboard carbon capture and storage (OCCS) and potentially nuclear power.

Newbuild lifespans sharpen the design challenge. Ships ordered today will often still be trading beyond 2050, so they must be designed to meet future regulations, reducing risk and cost across fleets. That increases the importance of combining near-term actions — energy-efficiency improvements — with long-term flexibility to burn low-GHG-emission fuels.

The commercial pressure is already here, even where the IMO is not. EU regulations and commercial demands are influencing investment decisions and operational choices now, regardless of when the NZF lands. Owners trading into Europe face carbon costs their competitors in other trades do not yet carry.

How should owners use the forecast?

Koukoulopoulos frames the report as a decision tool, not a prescription.

"It does not offer one answer for every fleet. Instead, it helps us ask the right questions: where does it make sense to act now, which options should remain open, and how can today's decisions remain robust as the market changes?" he said.

For Greek and Cypriot owners, that translates into concrete ordering strategy: specify efficiency measures — hull optimization, retrofits, operational improvements — on conventionally fuelled tonnage now, while keeping dual-fuel or convertible designs on the table for segments where methanol and LNG infrastructure is maturing fastest.

With the IMO's Net-Zero Framework still unresolved and regional rules likely to multiply in its absence, DNV's scenarios point to a decade in which flexibility, not fuel commitment, defines fleet strategy — and efficiency pays for itself in every one of them.