Model-based techno-economic evaluation of an electricity storage system based on Liquid Organic Hydrogen Carriers

A techno-economic evaluation and feasibility study of a stationary electricity storage system is conducted for an application in an industrial plant. The analysis is based on a model that includes both technological and economic components. It assumes that electricity is produced through wind turbines and photovoltaic systems. The produced electricity can be stored by conversion to hydrogen through electrolysis and reconversion through thermal energy converters. The system stores the produced hydrogen using Liquid Organic Hydrogen Carriers (LOHC). As carrier material, dibenzyltoluene is selected. The model includes investment costs and calculations to conduct economic analysis. It is used to create economically optimized systems that give realistic cost estimations. Technical and economic data are taken from in-house experiments, quotes from manufacturers and literature. The application is evaluated for the electricity supply to a BMW Group production site located in Germany. Results show that at present, converting excess energy to heat is a more economical option than electricity storage using LOHC. However, if the goal is to provide a majority (>75%) of the needed electricity with on-site renewable energy, an energy storage system becomes economical to use today. Based on assumptions for the year 2030 a completely self-sufficient energy supply system built in 2030 is competitive to the electricity purchase from the grid.