Shortage of repair yards with experience in conversions may hinder the take up of alternative fuel technology by the existing fleet, a new study shows.

UK-based classification society Lloyd’s Register (LR) found in a new engine retrofit report that repair yard capability and capacity concerns could thwart the uptake of alternative fuel technology onboard existing ships.

Class society has identified that retrofitting a significant number of the 9,000 and 12,900 large merchant vessels estimated to be part of the global fleet in 2030, could rapidly accelerate the maritime energy transition.

However, LR warns that these ambitions could be jeopardised by the limited number of repair yards currently capable of performing such conversions.

Claudene Sharpe-Patel, Lloyd’s Register technology director, said: “Without significant progress in this area, there could be as many as 20,000 commercial vessels relying on fossil fuels by 2050. We must, therefore, focus industry efforts on addressing the issues that LR’s Engine Retrofit Report raises such as yard capacity, conversion capability and system integration, helping stakeholders from the maritime value chain navigate the obstacles to installing future fuels technology on the existing global fleet.”

Key factors influencing the size of the market and the timing of retrofits, include the date by which shipping begins building only zero-emission vessels, as well as the age at which owners or operators decide to retrofit their vessels and the suitable engine types and bore sizes.

The study, which analyses the state of engine retrofit demand, capacity, and uptake, also points to the new skills in naval architecture, electrical engineering, and fuel handling which will be required if the industry is to use retrofitting as an effective tool to accelerate decarbonisation.

One of the key challenges with retrofits identified in the report is system integration, with significant issues such as accommodation for larger fuel tanks, space for fuel preparation equipment and ensuring safety measures are in place, all providing obstacles to rapidly retrofitting the existing fossil fuel fleet.

Techno-economic modelling data revealed in the study shows that the use of renewable methanol or ammonia would significantly increase fuel costs, in some cases more than doubling for vessels in all segments, however, a low-cost scenario, where alternative fuels decrease in price and carbon pricing rises, could tip the balance in favour of alternative fuels.

The study also highlights the importance of human factor considerations, underlining how the critical aspect of impact on crew members can often be overlooked during retrofitting.

As the study reveals, assessing ergonomics, roles and responsibilities, competency and training, procedures processes, and occupational health will play a crucial role in ensuring retrofitting is safe and effective for ship operators.