The continuous increase of the penetration of distributed generation in the distribution network poses more severe challenges for its full accommodation. In this context, an energy storage system can be installed to enhance the ability to accommodate renewable energy because of its high flexibility. However, the investment cost of brand new energy storage equipment is so high that the widespread application of storage system in the distribution system has been limited. This article proposes a method, which aimed at optimizing energy storage dispatching in a distribution network, and takes the use of second-use electric vehicles (EV) batteries into account. A calculation model of power battery second-use capacity was established, the upper and lower bounds of the initial capacity of second-use energy storage system (SUESS) can be determined after the reorganization of the retired batteries, and then a multi-objective optimal dispatching model for the distribution system with SUESS can be established with reference to the capacity attenuation model and the daily mileage statistics model of the electric vehicle. The case study results show that configured SUESS in the distribution network can not only meet the needs of the distribution network to fully accommodate distributed generation, but also delay the upgrade of the distribution network.
Economic Viability of Second Use Electric Vehicle Batteries for Energy Storage in Residential Applications
