Wasser ist die Schlüsselressource für die Energiewende mit grünem Wasserstoff. Der Water-for-X-Fahrplan von DECHEMA befasst sich mit dem weltweiten Ungleichgewicht von Wasserstoffnachfrage und Wasserversorgung.
Florian Ausfelder, Dominik Blaumeiser, Chokri Boumrifak, Daniel Frank, Maximilian Kotzur, Andres Lucht Uribe, Thomas Track
DECHEMA e.V., ACHEMA 2022
Secure and affordable energy is needed to achieve the European Commission’s Green Deal vision of a climate-neutral economy. In the context of political and economic stability, resilience is an additional global driver. The energy transition will involve new process designs, e.g. using renewable electricity directly instead of fossil fuels. On the other hand, there will be a high demand for converted and stored energy carriers based on (renewable) power such as hydrogen, gas, and kerosene, which are also known as Power-to-X (PtX) products.
A key contribution for the defossilization of our energy consumption will come from PtX technologies. The first step within these value-chains involves the generation of hydrogen via electrolysis. This hydrogen is then used directly or is utilized to produce other carbon- or nitrogen-based follow-up products. Thus, PtX processes depend heavily on the availability of highly purified water. Not only to produce hydrogen itself, but also for heat transfer via steam, as cooling water, and for cleaning. Additionally, process water is generated during the further production of other chemical products (kerosine, methanol, methane, etc.).
The interdependence of the management of water and energy is noted to date but not specifically addressed. While freshwater water resources worldwide are already being overexploited, the global (green) energy transition will place additional stress on their recharge ability due to an increased application of PtX technologies. The more hydrogen-based sustainable energy carriers we require, the more we put the resource of water at risk.
“Water-for-X”, as a concept for addressing the aforementioned issues is designed to
a) Highlight the vital contribution of PtX technologies for reaching net-zero goals
b) Reveal the importance of water in PtX processes as a unique resource for a safe and sustainable energy transition
c) Cope with the cross-sectoral dependency on the limited freshwater resources that are already largely used by agriculture, industry and the private sector
d) Guide decision makers towards a responsible water use. For a long-term use, the consideration of local social, economic and environmental aspects is important.
The Water-for-X concept is essential for sustainable and secure energy transition as an integrated, sustainable water management is indispensable for successful PtX solutions. Starting from the 2010s, DECHEMA provides both expertise on PtX processes in interaction with water management. Thus, the white paper is formalising the “Water-for-X” approach, provides the basis for his broad implementation and highlights its importance for a sustainable application of PtX technologies.