A Green Hydrogen Esslingen project demonstrates how energy-intensive green hydrogen production must be coordinated across industries in order to be commercially viable, including waste heat recovery, natural gas replacement, and energy-efficient operation.
Green Hydrogen Esslingen, a division of the green energy provider Polarstern, has been learning from the district’s green hydrogen production for more than 1.5 years. The electrolyzer with a 1-megawatt electrical output was formally commissioned in June 2021. According to Polarstern, a unique aspect of this hydrogen project is becoming more significant in light of the energy crisis and the urgent need to expand renewable energies: the diverse and cross-sectoral utilization of the benefits of green hydrogen generation for the energy transition. According to Florian Henle, Managing Director of Polarstern, “energy-intensive hydrogen production can be designed in such a way that it accelerates the energy transition on a global scale, going beyond replacing natural gas.”
The use of waste heat in the electrolysis process is crucial because it helps the energy transition in the heat supply and considerably improves the low efficiency of hydrogen generation. The efficiency rises from 60% to 90% in the instance of the Green Hydrogen Esslingen pilot project. The neighborhood market now has access to sustainable heat thanks to the waste heat.
The electrolyzer’s energy-transition-friendly operation gives significant energy market flexibility and lowers energy expenses. “It must be about more than just the amount of hydrogen produced in order to intelligently integrate green hydrogen production with its high demand for green electricity into the future energy market. An energy transition-friendly mode of operation for the electrolyzer is essential for the growth of renewable energies, whose generation is typically volatile. In this approach, the high energy requirement of electrolysis actually helps to reduce grid bottlenecks “Green Hydrogen Esslingen project manager Felix Mayer”
This promise for the German heat transition would go unrealized if green hydrogen came from other nations and continents. We can utilize the ensuing waste heat only if we manufacture green hydrogen here in Germany, claims Mayer. Utilizing waste heat directly improves electrolysis efficiency, which lowers heating costs for homes connected to the heating network. More clean heat results from the low-efficiency losses that occur during electrolysis, which were previously a drawback.
The operator claims that the Green Hydrogen Esslingen example demonstrates the potential benefits of the resultant waste heat for the real estate sector. The Esslingen pilot project will eventually generate 85 tons of renewable hydrogen annually. The calculations show that the generated waste heat may provide half of the heat needed for heating and hot water in a structure with 167 flats, a 14-story office building, and Esslingen University of Applied Sciences.
Electrolyzer operation that is friendly to the energy transition
Hydrogen will be significant in the future energy market since it can store green electricity. After all, the power grid will have more excess electricity, which needs to be used responsibly. In the Esslingen hydrogen project, energy is always transferred via power-to-gas-to-power (P2G2P) by coupling the electrolyzer with a bivalent combined heat and power plant. To do this, the electrolyzer responds to the price of electricity on the energy exchange and produces hydrogen when the grid has a large amount of renewable energy and the energy demand is relatively low. In the event that energy is not available, the combined heat and power plant has the capability of converting back into electricity. Both aim to combat grid bottlenecks and steadily lower the cost of electricity. In the living lab, the present Green Hydrogen Esslingen pilot project already uses only renewable electricity. The generated green hydrogen is added to the natural gas distribution system, which decarbonizes the customers to which it is connected.
More hydrogen requires greater application
Current research initiatives like Green Hydrogen Esslingen also highlight difficulties that are crucial for hydrogen application. There hasn’t been enough competent labor available up to this point to support the increase in hydrogen production. Long delays occur during operation for maintenance and repairs. Additionally, there is almost any market for spare parts because almost all of them are produced to order. The practice of hydrogen production would be made easier with more training and the adoption of DIN standards. Additionally, errors might be fixed more rapidly.
Currently, hydrogen expansion implementation and commissioning are also being hampered by raw material and supply difficulties. Additionally, there is a lack of incentives and financial certainty to start the still extremely expensive hydrogen projects. The lengthy approval processes also slow things down. There are already more than 60 hydrogen production projects using renewable energy in operation in Germany. A review by the Agency for Renewable Energies found that over 80 more are either planned or already under development.
