Optimal hydrogen storage sizing for wind power plants in day ahead electricity market

Wind energy generation does not often match energy market prices, which are tightly related to consumer demand. The coupling of wind energy conversion system with a storage medium improves the programmability of such generation plants, allowing suppliers to bid both in the energy and services market, and providing suitable profit margins for investors. Today, the ‘renewable hydrogen’ system, where hydrogen is produced by electrolysis, as an energy storage medium represents a way to fully exploit the economic opportunity of energy markets. Optimal sizing of a wind energy storage plant based on hydrogen technology has been analysed. Algorithms are applied in different simulations, varying some parameters such as efficiency and power rating of the plant's sub-systems, that is, electrolyser, fuel cell and storage tank (H2) with regard to their actual and forecasted cost. As a case study, a big wind farm in Sicily and the day ahead market prices in the Italian power exchange have been considered. The results show the incidence of the different components over the total system cost, fixing the possible values that make such a plant feasible considering the net present value.