Decarbonization Levers

How long will it take to future-proof logistics by decarbonizing transportation? It won’t happen immediately but it is happening already in steady, incremental steps. Discover how non-fossil fuels are starting to green every mode of transport.

In the far-distant future, our skies, seas, rail tracks, and roads will be fully decarbonized. Traditionally our various transport modes have leveraged different fossil fuels, particularly fossil gas, petrol, kerosene, diesel, and fuel oil which are extracted from crude oil and/or petroleum. And while the different fossil fuels possess varying attributes, they all have one thing in common – they add CO2 and other pollutants into our atmosphere. 

To future-proof logistics and decarbonize transportation, fossil fuels must be replaced with sustainable fuels. Already there’s extensive research and development in this area, and a limited amount of sustainable fuel is readily available. However, it will still take years or even decades for a solution to be found that’s both carbon neutral and fully scalable. Two types of sustainable fuel are currently considered – these are biofuels (based on bio-material such as used cooking oil) and synthetic fuels or e-fuels (based on renewable energy). There are many ways of applying these two basic components, resulting in different fuel products, as shown in the graphic below.

A barrier to decarbonization is the fact that, right now, we have limited amounts of biomass and waste material to transform into biofuel. And a vast amount of green electricity is needed to produce e-fuels. It’s unrealistic to imagine there will soon be enough biomass or renewable energy to produce sufficient sustainable fuel for the energy-intense aviation industry as well as the gigantic ocean vessels transporting 80% of global trade.

So which modes of transport should be using our biofuels and limited efuels going forward? Should it be aircraft or ocean-going vessels…or in the end should it be trains and trucks?

The aviation industry relies heavily on kerosene and is the mode of transport with the highest carbon intensity, although the fuel efficiency of aircraft has greatly improved in recent years. Even the most efficient aircraft needs around 150x the amount of fuel to move one ton of cargo compared to an ocean container vessel and 15x compared to a truck. 

While electric flight is not unrealistic to decarbonize aviation, at least for short-haul cargo flights, industry focus is firmly on sustainable aviation fuel (SAF), and there is something of a development race between SAF and sustainable maritime fuel (SMF). 

The mid-to long-term expectation is that aircraft will get the main share of drop-in biofuels and e-fuels, due to the lack of other realistic options for long-haul (cargo) flights. 

For generations, ocean container vessels have been powered by fuel oil or heavy fuel oil (HFO), the dirtiest fuel product. On the plus side, HFO is safe to store, easy to transport, and comparatively cheap. But it contains a lot of residuals such as heavy metals and sulfur and, compared to other fuel products, releases significantly more pollutants into the air when combusted. 

It makes sense that, like the aviation industry, the ocean freight industry is also looking into drop-in biofuels, especially those that are available today, and there’s very promising uptake across carriers, forwarders, and shippers.

In addition to these drop-in options, the ocean freight industry is exploring some non-drop-in fuels including ammonia and methanol. 

Ammonia is a gas that combines hydrogen with nitrogen and, since nitrogen makes up nearly 80% of our atmosphere, it is relatively easily extracted from air. The big advantage of ammonia is that no CO2 is needed to produce this fuel. However, one problem is yet to be resolved – high product toxicity. An ammonia spill in the ocean would have devastating consequences. 

Methanol, on the other hand, requires CO2 input for production but is biodegradable and so it’s easy to handle, store, and operate. 

To be produced synthetically in a way that is sustainable and scalable, both ammonia and methanol require green electricity. Further research and development will be needed in the years ahead to obtain sufficient quantities of green electricity. 

Trains started their shift from diesel to electricity a long time ago, especially in some parts of the world. Meanwhile diesel and liquefied/compressed natural gas (LNG/CNG) have been the main power sources for trucks for years. This transition to cleaner alternatives started well before the aviation and maritime industries and is developing fast for several reasons including lower complexity and easier reachability. 

The focus for heavy-duty and long-haul road vehicles is bio-LNG, bio-CNG, biodiesel, and battery electric particularly for first-mile, last-mile, and short-haul road vehicles. While biodiesel can be used as a drop-in fuel, bio-LNG and bio-CNG trucks require new purchases, both enabling decarbonization today. But watch this space – leveraging batteries or leveraging fuel cell technology will likely accelerate truck decarbonization on a larger scale starting 2030. 

The journey to fully decarbonize transport is a long one. Let’s jointly accelerate the transition by putting potential options into practice. Already today there are things we can do – DHL Global Forwarding insetting supports ambitious green goals and the book & claim mechanism is available to all shippers and forwarders. We don’t need to look far into the future; the levers for decarbonization are right in front of us.