Optimal hybrid storage planning under different tariffs in a microgrid

High penetration of renewable energy sources (RES) requires flexibility options as storage to keep system stability. The main barrier to implement the storage systems is the high costs combined with short lifetimes. To define a cost-optimal storage solution for a microgrid, an optimal design strategy for a hybrid storage system is proposed that consists of thermal energy storage (TES) and battery energy storage (BES). The hybrid energy storage system is expected to bring the high potential for cost-saving and capacity optimization to guarantee the minimal possible implementation cost. Furthermore, a new flexible tariff system called white tariff has been implemented to assess the potential savings achieved by a different configuration of storage implementation. BES has been compared with TES in a grid-connected settlement area equipped with PV generation and a centralized heat pump (HP). The storage systems have been compared under white and flat tariffs. The results show that the hybrid storage system has more potential in terms of cost-saving when it is used with the white tariff system.