System integration of wind-powered hydrogen refueling station

Abstract

As one of the carbon-free emission transportation method, fuel cell electric vehicles (FCEV) have become a very popular research topic for the recent years. However, as the fuel of FCEV, the hydrogen is usually produced by traditional steam reforming method, which is still not an environmentally friendly process.This report focuses on the study of infrastructure for hydrogen producing and refueling with zero carbon emission. An on-site water electrolysis hydrogen producing and refueling system powered by wind energy is designed and simulated in this study. The hydrogen is produced by on-site PEM electrolyzer powered by distributed wind turbine. First of all, the suitable petrol stations for such hydrogen refueling station modification are selected by GIS data analysis in Germany. By applying the constraints for safety and noise consideration, about 500 stations are selected from over 10000 petrol stations in Germany.Furthermore, the hydrogen producing and refueling system is designed and simulated by MATLAB modelling. The system is composed of five main components: wind turbine, PEM electrolyzer, compressors, storage tank and hydrogen dispenser. The technical and economic details for each of these devices are defined by a series of literature review. Besides, some parameters are from the real commercial products to make the system model more practical.A case study is built to validate the designed model for a 330kg/day H2 refueling station in Germany based on both current and future scenarios. The results show that more than 170 tons hydrogen can be produced annually. It can cover most of the hydrogen demand for the refueling throughout the year, which eliminates most of the hydrogen delivery cost from the other producer to the refueling station.In addition, by using the optimal pre-allocation control strategy, the system can become partially stand-alone with the grid. Only the high-pressure compressor system and cooling system for dispenser need energy supply from the grid, which is less than 1% of the system energy consumption. It means no extra grid reinforcement is needed. The wind energy can be used in a very efficient way. More than 95% of wind energy can be used for hydrogen producing while the other 5% supplies for the compressors as the electricity. The sensitivity research is also performed based on the climate data in a different year, which shows the stable operational behavior for the system.Last but not least, the economic analysis is carried out based on the case study. For the current scenario, the hydrogen production cost of the system is €6.1/kg and the overall dispensing price is €10.9/kg. It is expensive because the distributed wind turbine and on-site PEM electrolyzer are still costly technologies for now. However, with the R&D progress of these technologies, the production cost and the dispensed hydrogen fuel cost price for the future scenario will reduce to €2.6/kg and €5.1/kg respectively, which makes the hydrogen a very competitive fuel for the vehicles in the future.