Optimal capacity of shared energy storage and photovoltaic system for cooperative residential customers

In this paper, we consider a smart grid network where customers have their own photovoltaic generation system (PVS) but an energy storage system (ESS) is shared. The energy generated in PVS located at customer n's home can be immediately used for customer n at that time or be stored in the shared ESS. Customers all belongs to the same entity or different entities with common interest and seek a common goal. We find an optimal capacity of shared ESS and individual photovoltaic generation system minimizing the total energy cost. For a predetermined daily pattern of generation and load, we formulate an liner programming problem to decide an optimal capacity of the shared ESS minimizing the total energy cost. The total energy cost is the sum of expenses to buy electricity and to install the shared ESS. Numerical examples show that as compared with the case of individually installed ESS for each customer, the shared ESS can decrease the electricity demand to the main grid and the total energy cost is slightly reduced while meet the demand of electricity by appliances.