The importance of fuels in maritime and air transport is undeniable in the context of international trade. These sectors are fundamental pillars driving global supply chains, facilitating the exchange of goods, and connecting economies worldwide. However, this vitality is accompanied by significant challenges, mainly related to environmental pollution.
Maritime transport is the backbone of international trade and the global economy, as over 80% of the volume of goods trade is carried out by sea. Likewise, it allows for the transportation of a larger volume of goods over greater distances than any other mode of transport. Nevertheless, container ships annually release one billion tons of CO2 into the atmosphere. In this regard, according to Deutsche Welle (DW), maritime transport is responsible for about 03% of global annual emissions and, if it were a country, it would be among the top 10 most polluting in the world.
On the other hand, air transport allows for fast and convenient travel, facilitating economic growth, trade, and investments. The connectivity provided by this means enables the dynamism of global supply chains; however, in 2022, aviation accounted for 02% of global CO2 emissions, according to the International Energy Agency, having grown faster than rail and road transport over the last decades.
Types of fuel for container ships
Container ships use a variety of fuels, including:
• Heavy Fuel Oil (HFO): This is the most commonly used type of fuel for commercial ships and consists of a thick, viscous oil produced from crude oil. HFO has a high energy content, making it ideal for large and high-powered vessels; however, it also produces high levels of greenhouse gas emissions and pollutants such as sulfur and nitrogen oxides.
• Marine Gas Oil (MGO): This is a cleaner type of fuel than HFO, being a distilled product from the petroleum refining process. Although it is more expensive and has lower energy density, it produces significantly lower emissions of greenhouse gases and other pollutants.
• Liquefied Natural Gas (LNG): The use of LNG as fuel for this transport is increasing its presence year by year, constituting a good alternative fuel due to its non-polluting nature, which promotes the transition towards cleaner and more sustainable mobility; however, LNG is more expensive than HFO and requires special storage tanks.
• Biofuels: These are renewable fuels obtained from natural resources or organic waste, both animal and vegetable. Among the most notable advantages of biofuels is their ability to reduce pollutant emissions, and unlike fossil fuels and liquefied natural gas, these are a source of renewable energy.
• Electricity: Electricity is a clean fuel option that does not generate greenhouse gas emissions. However, electric container ships are still in the development phase and are not commercially economically viable yet.
Types of aircraft fuel
Aviation fuels are used for the propulsion of aircraft, and within these, we can distinguish three types:
• Jet fuel: the most common fuel for airplanes. It is a fossil fuel derived from crude and refined oil. It is generally used in turbine engines (jet engines and turboprops); however, as a fossil fuel, jet fuel is expected to become more expensive in the long term.
• Bio-kerosene: a fuel produced from renewable sources such as vegetable oils, animal fats, or waste. The aviation industry has been testing this fuel for several years on numerous test flights with the aim of providing an alternative to jet fuel.
• Hydrogen: a clean fuel that produces no greenhouse gas emissions. It is a clean and efficient energy source for aircraft, without the emissions of traditional aviation fuels; however, its use in this industry is still in the development phase, and there are some barriers to overcome, such as storage on the aircraft itself or at airport facilities. Hydrogen presents the following challenges: its low density, making it difficult to store compactly as it requires large containers to hold a significant amount of fuel; high reactivity, as it is highly reactive and can easily combine with other elements, leading to undesired reactions; and the cost of storing hydrogen safely and efficiently is high due to the specialized equipment and infrastructure required.
Green initiatives to reduce greenhouse gas emission
The fight against climate change is a challenge for all, and clearly for transportation industries as well. In this regard, below are some initiatives that will help both maritime and air transport to reduce their carbon emissions.
• Development of cleaner fuels, such as biofuel and hydrogen: Developing alternative fuels to fossil fuels, such as biofuel and hydrogen, has the potential to significantly reduce greenhouse gas emissions from the aviation and maritime industries; however, it is necessary for their cost not to be high and for them to be efficient in order to make them affordable.
• Improving engine efficiency: Improving engine efficiency can reduce fuel consumption by 3% to 4%, thereby enhancing fuel efficiency. This is particularly beneficial when considering a switch to more expensive alternative fuels or undergoing a fuel conversion. It will reduce both fuel consumption and greenhouse gas emissions. In this regard, airlines and ship manufacturers understand that increasing fuel efficiency is key to reducing emissions. That's why they have been exploring new designs, materials, and technologies that would sustainably enhance fuel efficiency through engine improvement.
• Utilization of carbon capture and storage (CCS) technologies: Carbon capture and storage is a method to reduce carbon emissions that are critical for addressing the issue of global warming. It's a three-step process involving capturing the carbon dioxide produced by energy generation, transporting it, and ultimately storing it underground.
--
In conclusion, maritime and air transportation are vital for international trade; however, they generate significant CO2 emissions due to the fuels they use. Container ships primarily use heavy fuel oil and liquefied natural gas (LNG), making it necessary to turn to cleaner alternatives such as biofuels to reduce their carbon emissions. In aviation, jet fuel is common, but alternatives like bio-kerosene and hydrogen are being sought, although the latter faces technical and cost challenges. In this regard, to address the challenge of climate change, the transportation industry has proposed some green initiatives, including the development of cleaner fuels, improvements in engine efficiency, and the use of carbon capture and storage technologies.
Considering the inevitable progress of the energy transition towards less polluting and CO2-neutral sources, the maritime and air industries cannot lag behind. Several factors are pushing these industries towards the adoption of green fuels aligned with the IMO's 2050 goals, such as regulatory pressures from the European Union and the International Maritime Organization, and demands from financial entities and end customers who increasingly prefer companies that contribute to reducing carbon footprint. In this regard, the future of fuels in maritime and air transportation seems to be heading towards renewable energy sources, painting a positive outlook for the efficiency and competitiveness of these industries, and for the environment.
