Abstract:The operation of residential solar photovoltaic arrays are typically dependent on net energy metering (NEM) tariffs or feed in tariffs that allow the array owner to treat the electricity grid as an energy storage device. This study presents a model and simulation results of a photovoltaic array paired with a second life battery pack, a partially degraded lithium battery pack from an automotive application, for stabilizing the electricity grid interactions of residential photovoltaic systems and reducing the overall residential demand placed on the electricity grid. Two numerical simulations are performed on the operation of a second life battery pack. The first used an equivalent system model for the battery pack and measured solar production and residential loads to evaluate the system performance using one second time steps. The second model used hourly time steps and round trip efficiency for the battery, coupled with weather data and residential demand, to determine the system performance over the course of a year. The numerical investigation shows that the PV and battery system can substantially reduce the quantity of solar electricity that is exported to the distribution grid and decrease the impacts of sudden fluctuations in photovoltaic output due to cloud cover while providing significant reductions in the electricity demand placed on the grid.