Economic feasibility of battery energy storage systems for replacing peak power plants for commercial consumers under energy time of use tariffs

Abstract

Abstract This work assesses the economic feasibility of replacing conventional peak power plants, such as Diesel Generator Sets (DGS), by using distributed battery energy storage systems (BESS), to implement Energy Time Shift during peak hours for commercial consumers, whose energy prices vary as a function of energy time of use (ToU tariffs). The economic analysis is performed by calculating the break-even point (BEP) for four different battery technologies: (i) lead-acid (OPzS); (ii) nickel-cadmium (NiCd); (iii) lithium-ion (Li-NCA); and (iv) Redox Flow (FeCr), using the HOMER Energy software in the simulations. One case study is analyzed for a commercial consumer connected to the MV network (Campinas/Brazil). The results show that, considering the updated 2018 BESS costs, none of the types of battery analyzed is economically attractive as a replacement for DGS. However, it can be observed that a 31%, 38% and 26% reduction in the costs of OPzS, Li-NCA and FeCr batteries, respectively, makes the installation of BESS viable. It is estimated that, in a 5- to 6-year horizon, these technologies would become economically attractive as a result of the strong decrease of the expected costs for the years to come.