Green Fuels For Ships and Their Challenges

As the maritime industry braces itself to decarbonize, concerns over carbon emissions escalate, thus intensifying the quest for alternate sources of energy.

Amidst this, an array of alternative energy sources are emerging and promise to redefine the future of maritime.

This article examines viable green fuel options for the marine sector, breaking them into three main categories: infrastructure, safety, and availability.

Biofuel

Biofuels have taken centre stage in the maritime industry’s shift towards sustainable fuel alternatives. Derived from organic materials, these fuels are gaining prominence due to their increasing availability across diverse geographic locations. Utilizing local biomass, agricultural by-products, and even municipal waste, biofuels present a promising avenue for reducing carbon emissions in marine shipping (“Biofuels for Marine Shipping,” U.S. Department of Energy).

One of the key advantages of biofuels lies in their compatibility with existing distribution networks, requiring minimal adaptations for bunkering infrastructure. This means that the transition to biofuels can be relatively seamless, offering a sense of relief to crew members who can easily monitor engine parameters without the need for significant adjustments or additional health risks.

Furthermore, extensive testing of biofuel blends on various engine types has demonstrated their efficacy without necessitating modifications to onboard fuel refining plants. This not only underscores the versatility of biofuels but also instils confidence in their viability as a sustainable fuel option for the maritime sector.

Methanol

Methanol, a tried and tested fuel in various transportation sectors, emerges as a formidable contender in the maritime industry’s quest for sustainable alternatives.

Numerous leading shipping companies have made strides by announcing the integration of methanol as an alternative fuel for their newly constructed vessels. However, the viability of methanol hinges upon the adoption of renewable production pathways.

One of methanol’s standout features is its widespread availability, owing to its utilization across diverse industrial processes. This versatility positions methanol as a flexible solution for reducing carbon footprints, as it can be sourced from natural gas or renewable resources such as biomass, carbon dioxide, and renewable power.

Major methanol production plants in regions like the Middle East, the U.S., and China bolster its global capacity, with industry leaders like Methanex ensuring a reliable supply chain for maritime applications.

Despite its advantages, methanol poses safety hazards that demand meticulous attention. Its hazardous nature necessitates careful handling to mitigate risks of inhalation or skin absorption.

Moreover, methanol’s nearly invisible flame during combustion presents challenges for fire detection, emphasizing the need for advanced suppression equipment and specialized training for shipping firms.

To address these concerns, the International Maritime Organization (IMO) provides guidelines for the safe management of methanol in maritime contexts.

Compared to alternative fuels like LNG or hydrogen, methanol offers distinct advantages in terms of infrastructure requirements. Minor adjustments suffice to accommodate its characteristics, including corrosion resistance and containment systems for toxicity, leveraging existing liquid fuel bunkering infrastructure. Notably, ports like Rotterdam and Antwerp serve as exemplars, boasting methanol handling facilities that set a precedent for global ports seeking to adopt similar measures.

Hydrogen

Hydrogen, the most abundant element in the universe, has also emerged as a prominent candidate in the pursuit of green fuels for the maritime industry.

Different types of hydrogen fuel have been examined, considering their availability, safety, and infrastructure requirements. The production method of hydrogen greatly influences its environmental impact and suitability for maritime use.

The main types of hydrogen include:

Green Hydrogen: Produced through electrolysis powered by renewable energy sources like hydroelectric, solar, or wind energy, green hydrogen is the most sustainable option. However, its supply is currently limited by the capacity of electrolysis infrastructure and renewable energy sources. Nevertheless, global renewable energy initiatives are rapidly increasing its production (International Renewable Energy Agency).

Blue Hydrogen: Generated from natural gas with carbon emissions captured and either stored or repurposed, blue hydrogen is less harmful to the environment compared to grey hydrogen but still relies on fossil fuels. The existing natural gas infrastructure, which can be adapted with carbon capture and storage (CCS) technology, makes blue hydrogen more accessible than green hydrogen in the near term (International Energy Agency).

Grey Hydrogen: The most common form today, grey hydrogen, is produced from natural gas via steam methane reforming without capturing carbon emissions. It takes advantage of the established natural gas pipeline and processing infrastructure, making it the most readily available hydrogen fuel currently (U.S. Energy Information Administration).

Despite its benefits, hydrogen’s high flammability requires strict safety measures, including leak detection systems and specialized handling, storage, and transportation procedures (European Hydrogen Safety Panel). As the maritime industry looks to hydrogen as a green fuel option, addressing these safety and infrastructure challenges will be essential for its successful integration.

Ammonia

Ammonia, primarily known for its use as a fertilizer in agriculture, has garnered attention as a potential marine fuel due to its ability to be produced using renewable energy sources. With around 175 million tonnes produced annually, ammonia boasts a substantial global production capacity, providing a solid foundation for its use in maritime applications (“Global Ammonia Production,” International Fertilizer Association).

However, using ammonia as a fuel presents significant safety challenges. Ammonia is caustic and hazardous, necessitating stringent safety measures to prevent environmental contamination and protect the health of crew members. Effective handling, storage, and emergency response plans are essential to mitigate these risks (“Ammonia as a Maritime Fuel: Safety Considerations,” Lloyd’s Register).

Establishing the infrastructure required for ammonia as a marine fuel involves several critical elements. These include bunkering facilities capable of withstanding ammonia’s corrosive properties, specialized storage tanks, and production facilities geared toward green ammonia production. Currently, most ammonia production relies on fossil fuels, but there is a growing shift toward environmentally friendly manufacturing methods.

In the maritime sector, evaluating the availability, safety, and infrastructure requirements of each fuel is crucial in the transition to green fuels. Addressing the technological, infrastructural, and regulatory challenges requires global collaboration.

For more information on each type of fuel, consult resources from the International Maritime Organization (IMO) and industry-specific research organizations.

End notes

With each wave of innovation, from biofuels to hydrogen, from methanol to ammonia, the maritime sector charts a course toward a carbon-intensive future. However, moving forward will require collaboration, integrity, and a strong commitment to protecting the environment. As global players unite to overcome technological, infrastructural, and regulatory hurdles, the vision of a sustainable maritime future draws ever closer.

Related Reading:

• Role of Seafarers in Maritime Decarbonization
• Why and How to Decarbonize the Marine Industry?

About Author

Azolla is a leading provider of sustainable solutions that drive decarbonization in the maritime industry. With a firm conviction that maritime professionals are key agents of change, Azolla endeavours to educate and empower individuals to embrace sustainable practices and lead the industry towards a carbon-neutral future. The writing team comprises of:

Kiran Shet, Head of Azolla
Aditya Srivatsava, Manager – Energy Efficiency & Decarbonization
Manav Chidambaran – Decarbonisation Specialist
Jothieswaran – Senior Naval Architect