This study investigated the behavior of vanadium redox flow batteries (VRFBs), which are batteries capable of easily switching between charging and discharging modes, making them a suitable option for storing intermittent sources of alternative energies (solar, wind, etc). Since different sizes of the battery provide varying voltages, optimal parameters for a particular home are key for implementation. These parameters, specifically the cell and tank volumes of the battery that are capable of providing consistent on-load voltage, were determined using data from a 13 kW solar array and a medium-sized house. Charge/discharge current values were used to run a mathematical model that provided on-load voltage over time graphs based on parameter input values. Using this model, the optimal parameter values were found to be 11.5 L for the cell volume and 103.7 L for the tank volume, which maintenained the on-load voltage well above 0.80 V (10% of cell standard emf)