The Journey towards Sustainable Maritime Transport

As the world increasingly turns its attention to sustainability, the maritime transport sector is making some progress towards reducing its environmental footprint. Responsible for around 90% of global trade, the maritime industry is a cornerstone of the global economy. However, it also contributes to approximately 3% of the world’s greenhouse gas (GHG) emissions, with demand expected to be multiplied by 3 by 2050. Addressing this paradox, the industry is embarking on a transformative journey towards sustainable maritime transport. This blog post explores the innovative solutions, collaborative efforts, and technological advancements opening the way for a greener maritime shipping.

The Urgency of Decarbonizing Maritime Transport

While shipping is generally considered to be more environmentally friendly compared to air or road transportation—given that an average container ship emits only around 4 grams (g) of CO2 per tonne-kilometer (t-km) versus air cargo’s more than 600 g of CO2 per t-km—the high sulfur content in marine fuel poses a serious environmental concern. Heavy fuel oil (HFO – Also known as bunker fuel), the primary fuel used in shipping because of its low cost, is thick and must be heated to flow freely for use in ship engines. Unfortunately, HFO contains many impurities, including sulfur. While the sulfur in fuel aids in engine lubrication, when it burns, sulfur oxides (SOx) are released into the atmosphere and can have a negative impact on both the environment and human health.

The International Maritime Organization (IMO) has been proactive in addressing this issue. The most significant measure to date is the IMO 2020 regulation, which limits the sulfur content of marine fuel to 0.5% by mass unless scrubbers are installed, down from the previous limit of 3.5% in 2012.

Innovative Solutions for Sustainable Shipping

1. Alternative Fuels

One of the most promising pathways to reducing emissions in maritime transport is the adoption of alternative fuels. Some of the leading candidates include:

Liquefied Natural Gas (LNG): After Russia cutted the gas supplies to Europe, LNG has become the go-to, making about 40% of European gas supply in 2023. While LNG is not completely carbon-free, it significantly reduces CO2 emissions compared to heavy-fuel oil as it lowers them by around 20% from “tank to wake” (from fuel production to onboard use). But from “well to wake” (from when fuel is added to the tank), the GHG footprint of LNG can often be worse due to CO2 emissions from its production and shipping.

Biofuels: Derived from organic materials, biofuels such as biomethane can provide substantial reductions in GHG. These fuels are often produced from waste, adding an element of circular economy to the energy mix.
Ammonia: Ammonia is emerging as a promising zero-carbon fuel for maritime transport. Produced either as green ammonia from renewable hydrogen and nitrogen or as blue ammonia from fossil-based hydrogen and nitrogen, it offers cost advantages by eliminating the need for carbon capture technology. However, ammonia is toxic and corrosive, and its combustion can produce nitrous oxide (N2O), a potent greenhouse gas. The technology to clean ammonia exhaust is still being refined. Additionally, ammonia’s low energy density requires larger tanks, impacting ship capacity and necessitating its use alongside a certain amount of conventional pilot fuel. Despite these challenges, ammonia’s potential to significantly reduce maritime emissions makes it a crucial player in the industry’s path to sustainability.

For more in-depth insights about the future fuel choices in the shipping industry, you can check this report by Global Maritime Forum.

2. Energy Efficiency Improvements

Enhancing the energy efficiency of ships is another critical strategy. This includes:

Hull Design Optimization: Modern hull designs increase hydrodynamic efficiency and reduce water resistance, therefore improve fuel efficiency. Advanced tools for simulation and optimization of hull design are necessary to make significant reductions in fuel consumption.
Propulsion Enhancements: Innovations such as wind-assisted propulsion systems harness wind energy to supplement conventional engines, reducing fuel consumption. Take the example of WISAMO by Michelin where, according to the company, the solution will reduce fuel bills by 10 to 20% per boat.

Digitalization and Operational Measures: Leveraging digital tools such as IoT and big data analytics can enable efficient route planning and speed optimization, resulting in substantial reductions in fuel use and emissions. Autonomous and remote-controlled ships can further enhance operational efficiency while minimizing human error. However, it’s important to acknowledge the cybersecurity risks associated with these advancements.

Collaborative Efforts and Industry Partnerships

Collaboration across the maritime value chain is essential for driving sustainable practices. Key stakeholders, including shipping companies, cargo owners, ports, and technology providers, are forming alliances to accelerate the transition. For instance, initiatives like the Global Maritime Forum brings together industry leaders to develop and implement best practices for sustainability.

Additionally, collaborations such as the Zero Emission Maritime Buyers Alliance (ZEMBA) play a pivotal role in promoting sustainable shipping solutions. ZEMBA, comprising major corporations committed to zero-emission shipping, leverages collaborative procurement approaches to create economies of scale for adopting new technologies. This not only boosts confidence in future demand but also reduces the significant costs associated with the transition.

Regulatory Framework and Policy Support

The IMO plays a pivotal role in setting global standards for maritime emissions. The IMO’s initial strategy aims to reduce the carbon intensity of international shipping by at least 40% by 2030, with a goal of achieving 70% by 2050, compared to 2008 levels. These targets are encouraging innovation and investment in cleaner technologies.

National and regional policies also support the transition. For instance, as of January 2024, the EU’s Emissions Trading System (EU ETS) has been extended to cover CO2 emissions from all large ships entering EU ports. The system aims to incentivize energy efficiency, promote low-carbon solutions, and narrow the price gap between alternative fuels and conventional fuels.

Final Thoughts

Despite significant progress, challenges persist on the path to sustainable maritime transport. High costs, infrastructure development for alternative fuels like hydrogen and ammonia, and technological uncertainty remain key hurdles. However, by embracing innovation, fostering collaboration, and supporting robust regulatory frameworks, the industry can navigate towards a sustainable future.