Energy Storage Electric Vehicle Charger for Public Charing

An energy storage system Electric Vehicle Charger is available in the public charging station together with normal Electric Vehicle Charger. Charging stations and mobile energy storage charging stations are built in the same public charging station. But mobile energy storage charger are not mobile. It is fixed installation on the charging parking spot. It allows for prior choice to use the mobile energy storgae charger as it's charging cost is 25% cheaper than normal ev charger.  At mid-night, use the normal ev charger to charge the mobile energy storage charger under cheaper electricity price to maximum ev charging operation profits.