PtX and Hydrogen in Transport, Your Questions Answered by VDMA’s Peter Müller-Baum

The Green Mobility Magazine team at Ibex Publishing sat down with the VDMA’s Peter Müller-Baum to answer your questions around the use of power to x (PtX) and hydrogen in transportation. Peter holds a master’s degree in Business and Engineering and is the Managing Director at the VDMA’s Power-to-X for Applications section.  

At its most basic level, how would you describe Power to X, and where do hydrogen and eFuels fit in?

Power-to-X technologies (or P2X or PtX) enable us to convert electricity from renewable sources such as wind and solar into other forms of energy. This energy can be stored in the form of chemical bonds: gaseous, for example as hydrogen, methane, and ammonia, or in the form of liquid eFuels. Hence, Power-to-X is to be understood as a collective term for “power-to-gas”, “power-to-liquid”, “power-to-chemicals”, etc.

How is hydrogen created?

There are different types of hydrogen and different ways to produce it. One possibility: Renewable electricity can be generated from wind and sun using wind turbines and solar cells. This electricity is used to split water into oxygen and hydrogen. This process is called electrolysis, and the hydrogen is called green hydrogen.

How are eFuels created?

The “e” in eFuels stands for “electric.” That gives you a first hint. eFuels are basically synthetic fuels produced using P2X technologies. You start with green hydrogen, as described, and use it in further process steps. There are various techniques for this, the Fischer-Tropsch, the methanol synthesis, the Dimethyl ether (DME) synthesis or the Ammonia synthesis, to name the most important ones. You always need CO2. It can come from industrial processes, from biomass or directly from the air via direct air capture (DAC).

What advantages does P2X have over direct electrification?

P2X and direct electrification are not necessarily in competition to each other, there is more of a competition between P2X and fossil fuels.

Some sectors and some applications can’t be directly electrified at all, for technological reasons or for infrastructural reasons. Think of heat that is needed for many industrial processes, for example in metal production and processing. Today, industrial process heat is often generated by burning natural gas – a gas that could be completely and safely substituted by synthetically produced gas. The Chemical and steel industries are already working intensively on alternative technology and process options. For the steel industry, hydrogen is obviously the way to a world without fossil energy carriers. In the chemical industry, the focus is more on the use of hydrogen derivatives such as ammonia and methanol.

There are many other applications where direct electrification or battery electrics reach their limits, where P2X works. In shipping, where long distances must be covered in one piece, or in aviation. Not to forget about power generation. Green electricity is not available when neither the sun is shining, nor the wind is blowing. That’s when P2X can step in. 

What disadvantages does P2X have over direct electrification?

Again, both complement each other like pieces of a puzzle. You need to look at what is the right choice for each single application. In some cases, it turns out that it makes sense to use electricity directly. In others, as said, this may not be possible or not wise to do, or there may not be enough electricity. Then hydrogen and its derivates can be an alternative. But it is important to consider that the production of hydrogen and eFuels consumes a lot of (renewable) energy and is therefore not very efficient. It would certainly be senseless to convert scarce electricity into hydrogen and use it in applications where electricity could have done the job directly. On the other hand, there is one thing that must not be forgotten: Unlike electricity, which must be generated geographically where it is needed, hydrogen and eFuels can be produced everywhere. If they are produced in regions where abundant solar and wind energy would otherwise go unused, efficiency hardly plays a role.

What is the potential for hydrogen for the broader transport sector?

Hydrogen and its derivatives will play a role in the transportation sector primarily where direct electrification or battery electrics do not or hardly work. This essentially means shipping, air traffic, and heavy-duty transport. In addition, hydrogen and its derivatives can also help to quickly move away from fossil fuels in the existing fleet of passenger cars, especially when, as already expressed, these eFuels come from regions with abundant solar and wind energy. For passenger cars, we have compared battery-electric driving to cars power with fuel cell or an internal combustion engine operated with eFuels, as described in the graph. The results show that all 3 options work. Best is BEV, ICE with eFuels from e.g. Chile ranks second. 

Heavy Vehicles: what is the status quo of P2X?

Many paths are being tried in heavy-duty transport. There are already trucks with batteries, for example. In a model test in Germany, trucks are also being tried out in which charging takes place via an overhead line, while the vehicle is in motion. Series-produced fuel cell trucks are also already on the road in Germany. And of course, hydrogen combustion engines are possible. These engines already exist in stationary applications, and there are plans to use them in mobile applications as well. We at the VDMA are in favor of technological openness and very much welcome the fact that development is taking place everywhere and in all directions. However, I think it is realistic that fuel cell trucks or such powered by a H2 engine will in future take a large share of the transport volume. Combustion engines running on eFuels will still play a role, especially in cases where existing trucks are still being used. They can rely on the infrastructure we have, we don’t need new pipelines, new tankers and tanker trucks, or new filling stations. eFuels can be blended with fossil fuels to speed up their use. For the environment, eFuels offer a very decisive advantage: When eFuels are used, the same amount of CO2 is released that was previously captured during production, therefore eFuels are CO2 neutral.

Air transport: what is the situation with P2X today?

In aviation, too, various paths must be taken to further reduce CO2 emissions: Today, for taxi flights or short to middle routes and for flights with fewer passengers or less payloads, electric flying with fuel cells or batteries is at the top of the agenda. Another way forward is sustainable fuels, such as those produced by P2X. They could soon significantly reduce emissions from flying and will be used especially for long distances and flights with heavy loads. As with trucks, flying with such synthetic kerosene emits only the CO2 previously captured. The production processes are ready for the market, but the fuels are still rare and expensive. Large-scale production is lacking. In Germany, the PtL roadmap shows how the market ramp-up of sustainable PtL kerosene can succeed. In this roadmap, policymakers and industry have agreed on the necessary conditions and measures to establish and expand the production of power-to-liquid kerosene over the next few years. The aim is to create the basis for producing at least 200,000 metric tons of sustainable kerosene annually for German air traffic by 2030.

Following the adoption of the so-called REDII at EU level, EU member states are also required to meet a binding overall target for advanced biofuels and renewable fuels of non-biological origin in the transport sector. Hence, flying will soon succeed with fewer CO2 emissions, even if truly climate-neutral flying may never become a reality due to other physical effects.

Marine transport: what is the state of affairs of PtX?

According to the 2018 Initial IMO GHG Strategy, the International Maritime Organization (IMO) wants to cut annual greenhouse gas emissions from international shipping by at least half by 2050, compared with their level in 2008, and work towards phasing out GHG emissions from shipping entirely as soon as possible in this century.

New propulsion concepts for shipping are therefore urgently needed. It is usually physics that sets the limits. Thousands of nautical miles in a row are hardly feasible with batteries. Already back in 2017, the VDMA presented a roadmap for the success of the maritime energy transition, which is still valid. In the summer of 2022, the two industry associations VDMA and VSM presented a jointly prepared Power-to-X Roadmap for the Maritime Energy Transition. To reach the goal, various chemical energy sources are currently being discussed for shipping, such as artificial ammonia or methanol. It remains to be seen which fuels and concepts will ultimately prevail. As many other stakeholders, we believe in a multifuel world for the future of shipping.

However, the internal combustion engine remains indispensable. In maritime shipping, it has proven its reliability over decades. With P2X, it will become the central component of an environmentally and climate-friendly solution.

What must stakeholders do in order to help P2X reach its full potential? 

As usual, there is no silver bullet. There are many different things that need to be done. From the governments, we generally speaking need the right political framework. We need incentives to move away from less climate-friendly solutions and invest in low-CO2-, CO2-neutral or CO2-free technology. For example, a price tag on CO2 would be very helpful.

Funding research helps to get solutions ready for the market quicker. Investment in education and training helps so that we will have the skilled workers we will need. Exchanging ideas and discussing the best solution will help. Finally, we also need to involve the population and explain to them why climate protection is so important, and that hydrogen is a central part of the solution. And, last but not least, we need an open-minded approach to technology in general. It does not help if politics believe that they know how the future looks like. We need to transform our complete industry and society rapidly and globally, that will work only if we can develop technologies and business cases – otherwise, we may reach the climate targets in Europe while other regions are increasing their emissions.

About: VDMA Power-to-X for Applications is a cross-industry platform for exchange, communication, and cooperation in the P2X community. It involves all important stakeholders, from the development of manufacturing processes through the production of synthetic fuels and raw materials using power-to-X technologies to the end customer. With our activities, we promote a holistic and technology-open approach to the transformation of energy systems, and we raise public awareness of environmentally friendly energy use and mobility.