Comparison of the water heating technique's impact on the sizing of a standalone PV-battery backup system assisting an intermittent primary energy source

This paper is a comparative study of the effect of various water heating techniques on the sizing of a PV-battery backup system for an intermittent grid supply. The optimal water heating configuration is found based on the smallest sizing of the backup system. Four popular water heating techniques are modeled and compared; the electric water heater, hybrid solar electric water heater, boiler water heater and the hybrid solar boiler water heater. A high energy consumption residential application is considered, realistic constraints are applied, and a detailed economic study is conducted in order to accurately quantify the advantages and consequences of each installed water heating technique.