Sizing and Operation of a Pure Renewable Energy Based Electric System through Hydrogen

Today, in order to reduce the increase of the carbon dioxide emissions, a large number of renewable energy resources (RES) are already implemented. Considering both the intermittency and uncertainty of the RES, the energy storage system (ESS) is still needed for balancing and stabilizing the power system. Among different existing categories of ESS, the hydrogen storage systems (HSS) have the highest energy density, and are crucial for the RES integration. In addition, RES are located in faraway regions, and are often transmitted to the terminal consumption center through HVDC (high voltage direct current) due to its lower power loss. In this paper, we present a power supply system that achieves low-carbon emissions through combined HSS and HVDC technology. First, the combined HSS and the HVDC model are established. Secondly, the rule-based strategy for operating the HSS microgrid is presented. Then, an operating strategy for a typical network, i.e., the pure RES generation station-HVDC transmission-microgrids, is demonstrated. Finally, the best sizing capacities for all components are found by the genetic algorithm. The results prove the efficiency of the presented sizing approach for a pure RES electric system.