Comparison of combining redox flow and lead‐acid batteries with On‐grid and stand‐alone photovoltaic systems

The present study deals with multi‐objective optimization of stand‐alone and grid‐connected photovoltaic systems in combination with lead‐acid battery (LAB) and flow battery energy storage devices, from economic, reliability, and environmental points of view. The desired electrical load is the one of typical household applications in remote areas of Kerman, Iran. In the off‐grid scenario, at hours the desired load cannot be met by the combined panel‐battery system, a solid oxide fuel cell (SOFC) is used as an auxiliary system to improve the system reliability. In the stand‐alone scenario, Pareto frontier in loss of power supply, annualized cost (ANC), and CO2 emission coordinate systems, with and without using SOFC is described. Furthermore, in the on‐grid scenario, according to the purchasing strategy, the money should be paid by each household to supply the desired electrical load is determined for both flow and LAB storage systems. Finally, the sensitivity analysis is done in both off‐grid and grid‐connected cases to find the effect of inflation and nominal interest rates on the ANCs. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019