ABS says conventional marine fuels and biofuels are likely to remain dominant through 2030. File Image / Pixabay

Classification society ABS says shipping's fuel transition is progressing through "multiple parallel routes" rather than a single pathway.

In its position paper release on Monday, The ABS View: A Practical Path Forward on IMO mid-term measures, the organisation said progress towards the IMO's decarbonisation goals must reflect the differing realities facing vessel segments across the global fleet.

“ABS’ assessment of fuel transition pathways confirms that the industry is moving forward, but through multiple parallel routes rather than along a single uniform trajectory,” it said.

ABS said ships operating on regular and predictable routes, such as container ships, ferries and cruise vessels, are generally better positioned to access alternative fuel supply chains and structured bunkering arrangements.

By contrast, vessels engaged in tramp trades, including bulk carriers and tankers, face more variable routing and commercial conditions that can materially constrain access to alternative fuels.

According to ABS, factors including fuel availability, infrastructure readiness, vessel deployment patterns, commercial structures and uneven operating conditions will determine the pace at which the industry's transition can occur.

The organisation noted that LNG remains the most developed alternative fuel pathway, supported by an established bunkering network and growing fleet uptake.

Methanol is emerging as a second major pathway, while ethanol is being considered as a complementary fuel option. Ammonia retains long-term potential but faces infrastructure, supply and operational readiness challenges that are expected to limit near-term deployment.

ABS added that conventional marine fuels, including blends incorporating biofuels, are likely to remain dominant through 2030, creating a risk that regulations based primarily on fuel switching could move faster than the industrial system needed to support them.

"The distinction matters," ABS said, arguing that progress towards the IMO's mid-term measures must be grounded not only in ambition but also in the operational realities of the fleet it is intended to govern.