A solution for replacing fossil fuels – Power-to-X
Recently the VDMA founded the 'Power-to-X Application working group' to develop the ideas and concepts around the important topic of reducing greenhouse gas emissions. As the search for the solutions to reduce greenhouse gas emissions globally continues, it has been acknowledged that fossil fuels must be replaced. Power-to-X application is being studied by the VDMA working group as it offers one remedy whereby green electricity is turned into synthetic fuels, gas or liquids.
The Paris Climate Agreement outlines that global warming should be reduced by less than 2°C compared to pre-industrial levels. Achieving this goal requires a significant reduction in greenhouse gas emissions: In all sectors - transport, buildings and industry - fossil fuels must be replaced by renewable energies.
A frequently discussed approach is to electrify all sectors as far as possible. As the share of ‘green electricity’ in the electricity mix is increasing, there is great potential in the long term to reduce CO2 emissions.
The role of mechanical engineering
Mechanical and plant engineering is the driver of a successful energy turnaround. This industry supplies the components necessary for the successful use of Power-to-X technology:
‘Power’ (e.g. wind energy)
‘to X’ (process engineering)
‘for A’ (application, for example, in mobile machinery or marine engines)
The companies' current research projects are primarily aimed at optimising existing technology and developing new processes. Which processes prove to be the most efficient in the end and which raw materials and fuels will be used is not yet foreseeable - the competition for the best solutions has only just begun.
What is Power-to-X and why do we need it?
The Power-to-X technology makes it possible to split water into oxygen and hydrogen using regenerative electricity. The hydrogen can then be used directly or further processed into synthetic gas or liquids, such as methane (power-to-gas), liquid fuels (power-to-liquids) or chemical raw materials (power-to-chemicals).
This process is not new and has been known since the beginning of the 20th century. Above all, however, the increase in regenerative power generation and the necessity to achieve CO2 neutrality with the Paris resolutions make it economically and ecologically sensible to push this technology forward.
Power-to-X is an important topic for sector coupling, because with Power-to-X green electricity can be stored. This is a key element in achieving Germany's and Europe's energy policy goals.
Power-to-X is can be applied to different industries that deal with fossil fuels and raw materials and are of strategic importance for those industries that are confronted with the ‘disruption’ of the combustion engine.
This direct electrification is not equally feasible for all applications. In shipbuilding or aviation, construction or agriculture, energy sources with a high energy density are required. Otherwise a combine harvester could not harvest a crop and a container ship could not steer its cargo across the ocean. A current-based ‘one-size-fits-all’ solution cannot be applied. The energy turnaround should therefore not remain a pure ‘electricity turnaround’, which focuses primarily on electrification, but should rather pursue an open-technology approach to reducing greenhouse gases.
What does this mean for the individual sectors?
In car traffic, electrification is a conceivable solution, as there is the possibility of setting up appropriate infrastructures. It would be difficult to switch to electric propulsion systems in international shipping and air, because the requirements for the energy density of fuels, range and service life of ships and aircraft demand different concepts. Synthetic fuels produced by Power-to-X can meet these demands and contribute to the de-fossilisation of the transport sector.
In the industrial sector, around two-thirds of the energy required for heat generation is covered today by the direct use of fossil fuels. As in the transport sector, there is also the possibility of direct electrification in industrial processes. However, industrial processes are very heterogeneous: In a foundry or a steel-works, for example, very high temperatures are required so that these processes cannot be electrified across the board. To reduce fossil fuels, efficiency increases and, in a further step, the switch to low-greenhouse gas or even greenhouse gas-free energy sources will be of importance. Greenhouse gas-neutral Power-to-X fuels will play a major role in the future, especially for high-temperature processes. This has the great advantage that the existing gas and heat infrastructure can continue to be used.
Power-to-X also enables the production of further raw materials for material use in the chemical industry. In many conversion processes, for example in the steel, cement or chemical industry, CO2 is used as a valuable material. In future, these processes will offer considerable potential for reducing CO2 emissions in industrial processes. The companies' current research projects are primarily aimed at optimising existing technology and developing new processes. Which processes prove to be the most efficient in the end and which raw materials and fuels will be used is not yet foreseeable - the competition for the best solutions has only just begun.
Currently, the biggest challenge is to bring the existing technologies to market maturity. This raises the question for companies as to what business models with Power-to-X look like and how they can be successfully established on the market. The most important prerequisite for companies is that they have a stable legal framework - because this is the only way to plan long-term investments in research and development and make them calculable! Another important factor is that Power-to-X projects only pay off for companies when CO2 emissions are priced in.
In politics, Power-to-X already enjoys a high profile and research funds are made available. A current example of research funding is the Program MARITIM green propulsion of the Federal Ministry of Economics.
Power-to-X technology offers European industry a great opportunity. In Germany, the discussion on how this technology can be used is particularly advanced. Many of the technology leaders located in Germany, Austria and Switzerland.
The key issue in the future will be the question of production capacities. To be able to offer fuels in enough quantities, they must first be produced. The advantage of Power-to-X is that, once the process is started, the generated power and raw materials can immediately be used in traditional applications or fed into existing grids.