Alternative fuelsA green course for road, air and maritime transport

E-fuels: Driving the mobility transition with green hydrogen

Alongside alternative plant-based fuels, so-called e-fuels are also the subject of intense debate. These are synthetic fuels produced using green hydrogen. They are considered green because the electricity required for water electrolysis comes from renewable energy sources. The idea is simple: Hydrogen reacts with CO₂ to produce methane - a key feedstock for green, synthetically produced, petroleum-free fuel.

One route to achieving this is the Carbon2Chem initiative - a globally unique large-scale project in which steel mill gases generated during steel production, particularly climate-damaging CO₂, are no longer burned but converted into valuable raw materials such as methanol or ammonia. The team processes these substances into a precursor for methanol, which can ultimately be used to produce fuel. The goal is to deploy the technology on an industrial scale.

Pure Oxyfuel: Turning CO₂ into synthetic fuel

The energy-intensive cement industry also offers opportunities for e-fuels. The Pure Oxyfuel process from thyssenkrupp Calvion  makes it possible to capture the climate-damaging gas CO₂ in concentrated form and use it, among other applications, to produce fuel. In this innovative process, clinker is produced using pure oxygen rather than ambient air for combustion. As a result, hardly any nitrogen enters the combustion process, producing highly concentrated CO₂. In this form, the gas can be captured and prevented from entering the atmosphere. Thanks to its purity and the use of additional technologies, the greenhouse gas can then be converted into a valuable feedstock. It can therefore serve as the basis for producing fertilizers, plastics and synthetic fuels.

In this way, various thyssenkrupp companies are contributing to the development and establishment of alternative fuels - and playing an important role in the decarbonization of mobility.

From plant residues to e-fuels: solutions for the mobility transition

For most of us, being mobile is a matter of course. We drive to work, fly abroad on vacation, and cruise tourism continues to grow. Mobility means freedom. But it also has its downsides. More than 20 percent of global CO₂ emissions can be attributed to transport. This is because the carbon stored in oil, natural gas and coal millions of years ago is released as carbon dioxide when fossil fuels are burned and enters the atmosphere.

Fossil fuels are finite and will inevitably run out sooner or later. At the same time, the ambition to power e-mobility exclusively with electricity from renewable sources is still far from reality. This means that transportation makes a significant contribution to climate change. We therefore need alternatives to conventional gasoline, diesel and kerosene - green, renewable alternatives.

Biofuels: Mobility powered by nature

The good news is that these alternatives already exist - for example, in the form of biofuels. The best-known examples are biodiesel made from vegetable oils and bioethanol produced from sugar cane, sugar beets or wheat. Because these plant-based raw materials grow back, their combustion in an engine can, in principle, be climate-neutral: The CO₂ released while driving is limited to the amount previously absorbed by the plants, creating a sustainable cycle.

Using an innovative technology, the experts at thyssenkrupp Uhde aim to enable the cost-effective, large-scale production of BtL fuel. BtL stands for “biomass to liquids” and describes precisely how these new biofuels are produced: Biomass - in other words, natural waste such as grass cuttings, straw and wood residues - is converted into high-quality aviation fuel and diesel. This is a major advantage over the previous generation of biofuels, which used edible crops such as rapeseed, corn and sugar cane. Given food shortages in many parts of the world, this practice had attracted considerable criticism.

Should the project prove successful, BtL fuel could be offered either in its pure form or blended with fossil fuels. It could be used in any engine or other propulsion system powered by diesel or kerosene, whether in passenger cars, trucks, trains, ships or aircraft. No conversion would be necessary. And the best part: These new biofuels can reduce CO₂ emissions by 90 percent compared with conventional fuels.