Practical energy storage systems are essential for matching the intermittent production of renewable power sources with the time dependent power demand of residences and businesses. This study assesses the technical viability of battery and hydrogen energy storage systems, scaled for a Canadian residential dwelling with low annual electric power consumption. The simulated consumption is an electric load, encompassing all major electricity demands within the house. The simulated load does not include space heating or cooling requirements. The conceptual dwelling uses a PV array to provide power to the load and storage system. System architectures were evaluated based on their ability to capture the maximum amount of energy from the PV array over the course of the simulated year.

Transient modelling was performed to thoroughly study two system architectures;​ an all-battery energy storage system, and a hybrid energy storage system, combining battery and hydrogen gas storage. The simulated systems were sized to meet a minimum load reliability of no greater than 15 load faults (no-power events) for the simulated year. Simulation of the all-battery storage system indicated that for a 10kWp PV array to meet the load demand with the required reliability, a 172.8kWh lead-acid battery bank was required. The battery system was capable of capturing 25% of every kWh of PV production, and had an overall electrical efficiency of 78%.

Simulation of the hybrid energy storage system indicated that the 10kWp PV array, combined with an 11kW PEM electrolyser, a 6 kW PEM fuel cell, a 20kWh lead acid battery bank, and a 10m3 hydrogen storage tank exceeded the reliability requirement, with only 6 load faults in the simulated year. The hybrid storage system was able to capture 58% of every kWh of PV production, and had an overall electrical efficiency of 48% (weighted average of battery and hydrogen efficiency).