MTF explores hydrogen bunkering gaps as IMO prepares guidelines for safe ship design

The Maritime Technologies Forum (MTF) has published a new report offering guidelines and key safety considerations for developing liquefied hydrogen bunkering systems and procedures.

The MTF is a group of flag States and classification societies that aims to bridge the gap between technological progress and regulatory process.

In relation to the adoption of liquefied hydrogen gas (LH₂) as a relevant fuel for the maritime sector, the MTF carried out a study on the current technological progress, and potential regulatory gaps, relating to liquefied hydrogen with emphasis on the bunkering of the fuel.

This report discusses the potential use of hydrogen as a zero-emission fuel to meet the International Maritime Organization’s (IMO) Strategy for the Reduction of GHG Emissions from Ships by 2050. It acknowledges the lack of experience in the maritime sector with hydrogen as cargo and fuel and the increased risks associated with its use as a fuel compared to LNG.

The IMO is currently working on the development of guidelines for the safe design of ships with hydrogen as fuel, with the target completion already at CCC10 in September 2024. Those guidelines will however focus on the ship installations and stop at the bunkering manifold on the ship.

In October last year, the leading maritime body revealed that its Sub-Committee on Carriage of Cargoes and Containers made significant progress on the development of draft interim guidelines for the safety of ships using hydrogen and ammonia as fuel.

The MTF emphasized that the details related to the bunkering operations are not part of the scope of that work. The goal of this work is to supplement CCC10 with input on the bunkering side of liquified hydrogen fuel safety.

Experience with bunkering of hydrogen for ships is limited and the design, operation and regulatory approval processes are complex, according to the MTF.

The project has conducted a review of existing standards and experience that can be applied to LH₂ marine bunkering and proposed structure and main topics of importance for bunkering guidelines which can help to accelerate the development and standardization of LH₂ bunkering procedures for ships.

The key observations of the report include:

• The properties of hydrogen, and in particular the very low temperature of liquefied hydrogen, mean that the experience gained from LNG bunkering cannot be re-used directly;
• The bunkering process will be more complex than it is for LNG, since no nitrogen can be present inside the piping systems when liquefied hydrogen is introduced, as this will freeze and clog the systems;
• The material choices and need for more insulated components and piping will also be slightly different.
• The development of vessel-specific procedures for bunkering operations, such as more automated bunkering procedures, will be necessary.
• The added complexities will mean that the need for crew training and certification is of even higher importance than for other bunkering processes.
• The Safety Management Systems should be updated to cater for the additional safety aspects with liquefied hydrogen bunkering,.

“With the current lack of international standards covering bunkering of liquefied hydrogen, these guidelines are especially important to help industry develop and advance safer bunkering operations. This is why the Flag state members of MTF are jointly submitting this report to the IMO to provide recommendations and offer a framework to consider when developing liquefied hydrogen bunkering requirements,” Alf Tore Sørheim, Acting Director General of Shipping and Navigation at the Norwegian Maritime Authority, said.

“Hydrogen is going to continue to play an important role in the energy transition, both as a marine fuel and as a cargo, which is why it is critical to develop standards to support its safe bunkering. The introduction of these guidelines and their submission to IMO are key steps in addressing the challenges around liquefied hydrogen bunkering,” Knut Ørbeck-Nilssen, the CEO of DNV Maritime, added.

Currently, there are no international standards covering the bunkering of liquefied hydrogen. However, the MTF notes that information collected from ongoing developments for related areas, as well as the experience gained from the Norwegian ferry MF Hydra, could serve as the basis for the guidelines and recommendations.

MF Hydra, the world’s first liquid hydrogen-powered ferry operated by Norwegian company Norled, started sailing on zero-emission hydrogen in March last year.

Delivered in 2021, MF Hydra is 82.4 meters long with a capacity of up to 300 passengers and 80 cars. It will be able to reach a speed of 9 knots with fuel cells of 2×200 kW and generators and 2×440 kW which will power Shottel thrusters.

The ferry is equipped with an 80 cbm tank for hydrogen storage and is expected to reduce its annual carbon emissions by up to 95%.