Discover the cutting-edge technology of hydrogen ship propulsion and its role in transforming marine mobility. Explore maritime transportation’s sustainable and emission-free future with this innovative solution, paving the way for a greener and more environmentally conscious maritime industry.
Hybrid hydrogen ship propulsion is an exceptionally promising solution for emission-free marine transportation. It is much less widespread in the spectrum of alternative drive systems than diesel and gas generators. However, development is progressing at a remarkable pace, as it should. This is also thanks to various research and funding programs that strive to make hydrogen suitable for ship propulsion. Hydrogen is thus an advantageous energy carrier for shipping.
With our many years of knowledge in electric drives, we always keep a close eye on the growth of new technologies.
Hydrogen-based Propulsion System Function
Essentially, ship propulsion on this base always entails an electric motor in the drive train. The energy for this drive is developed in fuel cells, for example. Fuel cells are devices that alter the energy produced by a chemical reaction between a fuel and an oxidizing agent into electrical energy. During the process, water, electrical energy, and heat are produced. The fuel cell reaction in ship drives automates without the need for artificial induction. Instead, it is catalyzed. All needed is a continuous supply of oxygen and hydrogen from the environment. This must be stored and carried on the ship in high-pressure or refrigeration tanks. As an option for the fuel cell, there are also hydrogen engines. These generate electrical energy in a process analogous to traditional fossil fuel generators. The hydrogen can also be used as a gas or bound in a carrier liquid, such as LOHC technology.
Hydrogen is Being Used With Our Electric Motors.
“Hydrogen ship propulsion systems typically require one or more electric motors for operation.”This development is interesting for us at the Merchant Navy. We know about extremely efficient motors, including the most important converters and the corresponding control units. Thanks to the options available to us for making individually flexible adjustments to existing systems, Electric motors can also be utilized for hydrogen drives on ships. Today, these electric and hybrid drives are already used on many vessels. We have seen many being electrified successfully. Almost over 80 ships and boats.
The Fuel Challenge
The main issue is the fuel itself. As well as its storage and transportation. These factors pose major challenges. In today’s mobility sector, there are many viable storage variants available. Two of them are particularly widespread:
Hydrogen is stored in pressure tanks during high-pressure gas storage. For this variant, the space needs of the tanks are the biggest concern. To achieve ranges comparable to heavy oil or diesel, one must highly compress the hydrogen. The ship requires less space as the compression increases. This solution has its limits. These limits are imposed partly by the pressure capacity of the tank designs. In part due to the energy required for compression.
At full compression, hydrogen is in its liquid phase. This is, therefore, the point of highest space efficiency. Extremely low temperatures are needed for this to happen. At -253 degrees Celsius, the element liquefies. You can store it in cryo tanks and transport it easily. However, one issue that cannot be avoided is “evaporation losses.” Storing hydrogen for an extended period after liquefaction can be particularly challenging. Ideally, this would need a suitable infrastructure, including producing cryogenic liquid hydrogen in or near the ports.
Despite all the challenges, the following holds: Progress is gathering momentum. Europe, and Germany in particular, are actively promoting the advancement of research and development. Various hydrogen propulsion technologies include smart and efficient storage and transportation solutions. They are currently being driven forward energetically against this backdrop. The outlook for ship propulsion is extremely promising.
Hybrid Hydrogen Ship Propulsion Systems
Hydrogen ship propulsion offers advantages comparable to those for other forms of mobility. The most prominent of these benefits is environmental friendliness. Hydrogen as a fuel source produces no harmful emissions, making it environmentally friendly. Energy is only required for its generation and storage. However, this energy can be obtained from green sources. Wind energy is an obvious choice for maritime shipping. Hydrogen propulsion promises climate neutrality in the long term.
Additional benefits include:
- Climate neutrality
- Unlimited range of ships
- Prospects for significant cost reductions in the medium-term
- Comparatively safe with low accident rates
- Easy expansion of the hybrid DC system
Another major advantage is running the system continuously without charging breaks. Storing cryogenic or highly compressed hydrogen is becoming increasingly feasible as it would be necessary with purely electric drives. The ship drive system can achieve excellent ranges. Refueling operations can be performed quickly and easily during loading, unloading, or berthing with adequate infrastructure.
Areas of Application – Suitability and Challenges
Hydrogen ship drives have several potential applications. These include ferries that operate on fixed routes, making it easy to generate and refuel hydrogen efficiently. Similarly, supply vessels used by energy companies for offshore wind farms or drilling platforms could benefit from hydrogen power.
Hydrogen and Fuel Cells
Hydrogen shows massive potential for ship propulsion in terms of climate footprint and overall sustainability. And there are many other benefits, such as a high level of protection. The production, transfer, and preservation of hydrogen continue to be a challenging task. At the same time, these tasks could be more robust from a technological point of view. The problem is implementing them economically. Solutions to this are well underway and may even reduce costs in the long term. We at the Merchant Navy are following the developments with great anticipation and would like to do our part in shaping future technology. With our existing marine services and extensive experience in electric motors, we are already waiting in the wings.
