The efficiency of the use of hydrogen depends strongly on the application and the sector. The structure of this within the context of the Belgian energy system is one of the key questions that will be investigated over the next five years as part of the PROCURA project (in full: Power to X and Carbon Capture & Utilisation Roadmap for Belgium). “Synthetic fuels will probably be more suitable for end applications in the transport sector,” says Pieter Vingerhoets of VITO/EnergyVille. “Through PROCURA, we want to establish a clear and comprehensive taxonomy of hydrogen. What are the best applications to use it directly, and when is it better to convert it into other synthetic chemicals first? “Within the project, various possible solutions, which could result in a low-emission and safe energy system by 2050, are being tested to determine their potential. We are looking into the scalability of the technology, affordability and the possibility to maintain a balanced energy system with supply security.
Obviously, hydrogen is only one of these solutions. The energy carrier is also part of the wider Power-to-X (P2X) concept, in which cheap electricity is used to produce certain synthetic chemicals and fuels (so-called ‘e-fuels’). P2X is a welcome solution, both for Belgium and for Europe, where the energy transition depends on the further expansion of renewable electricity. Lodewijks: “On the one hand, P2X is important for balancing our power system, on the other hand, the energy transition needs molecules in a number of sectors.” By the end of the PROCURA project (around 2025), a detailed and clearly calculated scenario should be available, which demonstrates how P2X can contribute to the future Belgian energy system – including concrete policy actions that will have to be taken before 2030. “We are also considering how the use of P2X in Belgium – where the potential for renewable energy is relatively limited – relates to the situation in neighbouring countries, as well as investigating options for importing molecules from regions where this potential is much higher.”
PROCURA was launched on 1 March 2020 and is being sponsored by the federal Energy Transition Fund – the budget is 4.5 million euros. It is an interdisciplinary partnership between Belgian knowledge organisations, all providing their own contribution: imec, WaterstofNet, KU Leuven, VUB, the University of Liege and finally VITO/EnergyVille.
The consortium is being led by imec, which provides its expertise in the field of nanomaterials. “In the field of energy, we were already working with technologies like solid state batteries, but we now also want to apply our knowledge to electrolysis systems,” says Joachim John, Programme Manager at imec. “The surface properties of materials on a nano scale, for example, play a key role in the efficiency of electrochemical reactions that convert light directly into hydrogen (which can then be converted into so-called solar fuels after adding other chemicals).”
The potential of these solar fuels is a separate work package within PROCURA. Within these packages (there are seven of them), the focus is on the development of technology starting from the basis. But at a higher level, the results of the work packages are combined and incorporated into models and possible roadmaps – each targeting the year 2050. “That makes this project truly unique,” says Lodewijks. “It makes it both a high-level study and a fundamental study into new P2X technology. The insights gained from the work packages are incorporated into system models, which we then scale up to a Belgian level at VITO/EnergyVille. This modelling at system level is exactly what we specialise in.”
Electrolysis of CO2
Within PROCURA, the potential of promising CCU technology is also being studied: the direct conversion of CO2 into “green” molecules using water and electricity (which in turn should ideally come from renewable sources). This “CO2 electrolysis” could operate flexibly based on the electricity supply, without requiring electrolysis of water as an intermediate step. This may allow the technology to act as an alternative to hydrogen-based strategies. “Chemicals such as methanol, for example, could be more suitable for synthetic fuels,” says Bulut. “Its energy density is much higher, so methanol is easier to transport.”
The disadvantage is that the technology is still in its infancy. “But it has great potential for producing other molecules as well,” says Jan Vaes, Sustainable Chemistry Programme Manager at VITO. “For example, we are also investigating the production of ‘green’ formic acid from captured CO2 in this manner, and its use as a high-performance chemical.”
Even though PROCURA was set up using the Belgian energy system as a basis, the methodology used is generic, so it can also be applied to other countries. “This is another aspect that makes this project unique; it is unrivalled anywhere in Europe or the world,” says Lodewijks. However, the condition is that the energy system should mostly operate on renewable energy (by 2050). Whatever the results of the project, the share of this in the energy mix will have to increase dramatically in any case. Vingerhoets: “We currently need a lot more solar and wind energy to create a balanced system in which, for example, locally produced, green chemical energy storage plays a key role. So we still have a long way to go.”