Coupling an energy storage to a photovoltaic (PV) system not only increases the self-consumption but also solves the over-voltage issues if the cycling of the storage is properly controlled. Whatever the application the storage is used for, the primary concern of the system owner is to maximize the profits. Therefore, this paper addresses an energy management system for a PV system coupled with battery energy storage, which maximizes the daily economic benefits while curtailing the power injection to the grid in such a way that helps to mitigate over-voltage problems caused by reverse power flow. A time dependent grid feed-in limit is proposed achieve this objective. The daily operational cost that includes the energy cost and the battery degradation cost is considered as the objective function. The non-linear constrained optimization problem is solved using dynamic programming. The analyses are made to investigate the economic benefits of charging the battery from the grid. It is found that there is a possibility for these systems for participating in load-levelling if batteries are charged from the PV system. In order for that to be feasible, the peak-hour sell-back price for the energy from storage should be higher than the off-peak utility electricity price.

• This paper presents an energy management system that maximizes the daily economic benefits of a PV system with battery storage while also helping to mitigate over-voltage problems on the grid.
• The objective function for optimization includes not only the cost of energy but also the battery degradation cost (BDC), which accounts for both cycling and calendrical aging.
• The optimization problem is solved using dynamic programming.
• A key finding is that for charging the battery from the grid to be economically viable, the sell-back price during peak hours must be higher than the utility electricity price during off-peak hours.
• When comparing DC-coupled and AC-coupled system configurations, the study found that the daily operational costs were negligibly different.