Green Hydrogen: A High-Stakes Game Changer for Maritime Decarbonization
Hydrogen has emerged as a prominent subject of interest not only in the marine industry but across various sectors. Analyzing hydrogen requires a comprehensive understanding of its applications and characteristics over time as it has been identified as a potential low-cost chemical energy source. The cost-effectiveness of hydrogen is a primary driving force behind its integration into the maritime industry.
As an energy carrier, that is able to contain energy and be then converted to other forms such as mechanical work or heat, hydrogen presents an intriguing solution for tackling the intermittency and variability of renewable energy sources. Its potential for long-term storage and diverse applications further enhances its appeal. However, it is crucial to recognize that there are multiple types of hydrogen, each with distinct production methods and environmental impacts.
Green hydrogen, derived from water splitting using renewable energy (electrolysis method), is considered climate neutral, while grey, blue, or brown hydrogen relies on fossil fuel mixtures, emitting carbon dioxide during production. Even blue hydrogen, produced with Carbon Capture and Storage methods (CCS), is not entirely without concerns, as it may still release methane. In 2021, only 4% of the total production came from electrolysis 1.
The widespread production of hydrogen is located near its point of use. This results in its rarity as a shipping product and non-existent use as a fuel. Some experts propose employing hydrogen primarily on smaller ships that can refuel frequently, such as tugboats, harbor crafts, and offshore supply vessels. Alternatively, hydrogen could play a role in larger vessels through e-fuels like Ammonia. However, its low density (0.08375 Kg/M³ at ambient temperature) poses challenges in transporting large quantities of the gas, even when liquefied. And this is despite its energy content, which is three times higher per kilogram than MGO (120 MJ/Kg vs. 40 MJ/Kg).
Hydrogen’s volatility and the risk of loss emphasize the importance of synthesizing Methanol and Ammonia as viable alternatives. Time-sensitive technologies are crucial in mitigating such concerns.
The Total Cost of Ownership (TCO) is a critical factor that will determine the long-term viability of hydrogen and other e-fuels. While technologies like Carbon Capture and Storage (CCS) for synthesizing Green Methanol show promise, their higher costs, due to privately owned technologies, may hinder their financial attractiveness compared to hydrogen.
A lack of bunkering infrastructure, training, and regulatory framework inhibits the seamless integration of hydrogen as a fuel in the maritime industry. To address this, DNV, a world leader classification company, has published a comprehensive handbook for hydrogen-fueled vessels, offering guidance on design, construction, safety, risk reduction, engineering specifics, and implementation for maritime applications.
Although hydrogen’s price (green hydrogen ranges from $6 to $8 per kilogram and the grey/brown one is around $2/Kg 2) is currently a significant obstacle in competing with conventional fuels, its abundance and potential for economies of scale provide hope for overcoming future challenges.
Despite the drawbacks listed, this chemical element is at the center of maritime transition projects. For example, the port of Rotterdam hosts one of the most promising hydrogen projects, with ambitious plans to deploy 50 zero-emission vessels by 2030, aimed at reducing CO2 emissions significantly. Collaboration between the government, academia, and private sectors seeks to decarbonize major routes in North West Europe.
In a nutshell, hydrogen presents a dualism between its capacity to substantially reduce CO2 emissions and the storage volume required, which is significantly larger compared to traditional fuels like MGO. While it exhibits great promise, addressing technical and infrastructural barriers will be crucial to its successful implementation and contribution to decarbonizing the maritime industry.
1 https://www.irena.org/Energy-Transition/Technology/Hydrogen
2 https://www.sgh2energy.com/economics
© Riverlake – 2024
