Cost of Hydrogen by Exploiting Offshore Wind and PEM Electrolysis Synergies

The use of hydrogen as an energy carrier for stationary and automotive applications is gaining increasing attention. Currently, generating hydrogen via electrolysis from electricity supplied by the grid is simply too expensive. Coupling electrolysis directly to renewables can avoid a number of costs incurred by both the renewable source as well as the electrolyzer. Specifically, PEM electrolysis coupled to off-shore wind has numerous synergies that have yet to be fully explored, quantified and modelled. Our study quantified these trade-offs while looking for optimal US locations for deployment. Through this project, we were able to develop and refine a model to calculate the LCoH under a variety of generation scenarios, including variable water depth, wind power output, distance to shore, and pipeline parameters, as well as investigate how those variables impact pricing for several hydrogen end use cases. We modeled the integration of hydrogen electrolyzers directly with a wind turbine to determine the optimal placement of the electrolyzers on a windfarm and evaluated the necessary power electronics under these various scenarios and the impact on total cost. An integrated system design was developed and evaluated. We also studied the tolerance of standard Pt and Ir catalysts for saltwater ions, as a function of catalyst loading and salt ion composition and concentration. Seawater intrusion tests were also performed to evaluate the sensitivity and recoverability of PGM catalysts in case of water purification system failure. Alternative catalysts with higher saltwater tolerance have also been investigated and optimized for long-term durability under operation. Integrated electrolyzer testing at NREL was performed by installing a 250 kW PEM electrolyzer at their ESIF facility for simulated wind turbine performance tests. Detailed wind turbine output simulations were prepared based on real wind turbine data, and integration of those simulations with the ESIF test bed electronics, including high frequency input and output logging was developed and installed. We performed 500 h conditioning, followed by 200 h of intermittency testing using simulated wind turbine power output to control the electrolyzer operation and assess the impact of rapid voltage modulation on electrolyzer performance and durability. Acknowledgement: The project was financially supported by the Department of Energy under Grant DE-SC0020786.