Optimal use of second life battery for peak load management and improving the life of the battery

Impact of petroleum based vehicles on the environment, cost and availability of fuel has led to an increased interest in electric vehicle as a means of transportation. Battery is a major component in an electric vehicle. Economic viability of these vehicles depends on the availability of cost-effective batteries. Subsidies provided by the government will be instrumental in the initial success of electric vehicles. However, in the long run for the commercial success of electric vehicles the economics have to be self-sustained. Batteries used for transportation purpose cannot be used once the energy capacity reaches 70%-80%. The remaining capacity of the battery can still be utilized for secondary purpose like powering a building during peak load hours and reducing the carbon foot print. Owner of an electric vehicle would be benefited if a market for the used electric vehicle batteries is created. These batteries are called second life batteries. Commercial building peak load reduction is considered in this study. This work deals with using second life battery for peak load management and to analyze the cost effectiveness of the second life battery to be used for powering a commercial building. Battery is the main component in this study and increasing the life of the second life battery using Battery Life Estimator (BLE) is discussed. An optimal solution for incorporating peak load management, cost saving from the use of second life battery and lifetime of the second life battery is achieved using a rule-based control for the parameters.