The Impact of Hydrogen Vehicles on the Optimal Scheduling of Stand-Alone Microgrids

Environmental problems arisen from burning fossil fuels results in the development of renewable resources for electric power production in the power networks, and electric and hydrogen vehicles in the transportation systems. Among the various renewable sources, wind and photovoltaic power plants have grown more and are widely used to supply loads, especially in microgrids. In this paper, optimal scheduling of a stand-alone microgrid containing wind turbines, photovoltaic power plants and fuel-based generation units is performed. Due to the variation in the wind speed and sun irradiance, the output power of wind turbines and photovoltaic power plants varies. To reduce uncertainty of output power of renewable resources, energy storage system such as electrolysis device- hydrogen tank- fuel cell device can be used in the stand-alone microgrid. The hydrogen produced by electrolysis system is stored in the hydrogen tank. The stored hydrogen can be used in the fuel cell device for electric power generation or sold to the hydrogen vehicles. When, the generated power of renewable resources is less than the required load, the generated power of the fuel cell can compensate all or some of electric power shortage. Besides, the hydrogen vehicles can purchase the electric power stored in their batteries to the microgrid, and participate in the vehicle to microgrid scheme. In this paper, for optimal scheduling of the stand-alone microgrid, operation cost of fuel-based microgrid, the reliability cost associated to the penalty of load curtailment, the income from the sale of electricity and hydrogen and the cost of purchasing electricity from hydrogen vehicles are considered. To clearly investigate the impact of renewable resources, hydrogen storage system and hydrogen vehicles on the optimal scheduling of the stand-alone microgrid, numerical outcomes of a microgrid simulated in the MATLAB software are given.