Techno-Economic Analysis of Hydrogen Production & Storage Technologies for Grid Scale Applications

Abstract

The use of fossil fuels in energy sectors leads to harmful emissions into the atmosphere, includ ing carbon dioxide (CO2). This results not only in environmental pollution but also in detrimental effects on human health. Emphasis is being placed on the deep decarbonization of the energy sector to mitigate climate issues and minimize the increase in global temperatures. As fossil fuels are replaced by renewable energy sources, storage systems are needed to address the intermittent nature of renewable power outputs and to enhance the reliability of the electricity network. Hydrogen storage systems could be a potential medium for long-term electricity storage, and extensive research is currently underway to transition to a hydrogen economy. Traditional hydrogen production methods involve byproduct gas emissions; therefore, there is a strong emphasis on producing green hydrogen using electrolyzers. This study aims to conduct technical and economic assessments of both traditional and green hydrogen production and storage technologies in electricity networks.

A mixed-integer nonlinear programming model is developed, and a test microgrid is selected for the study. Wind power generation and conventional generators are considered the renewable sources for this system. Cost minimization is the objective function of the model, encompassing the capital expenditure of hydrogen storage systems and the operational expenditure of the sys tem. Scenarios are generated based on seasonal variations in wind speed and demand, and the model is studied for different types of hydrogen production and storage technologies. Results suggest that incorporating a storage system would enable the management of seasonal wind variations and reduce operating costs by charging during demand valleys and discharging during demand peaks. Storing green hydrogen instead of grey hydrogen in compressed gaseous form is found to be the most economical option when considering long-term technology costs. Conversely, storing hydrogen in liquid form is currently too expensive for electricity storage and requires further technological advancements to reduce costs. In conclusion, using a hydrogen storage system in the electricity network would provide economic benefits and improve network reliability.