The BOS typically consists of structures for mounting the PV arrays or modules and power-conditioning equipment that adjusts and converts the DC electricity to the proper form and magnitude required by an alternating-current (AC) load. The BOS can also include storage devices, such as batteries, so PV-generated electricity can be used during cloudy days or at night.The BOS typically consists of structures for mounting the PV arrays or modules and power-conditioning equipment that adjusts and converts the DC electricity to the proper form and magnitude required by an alternating-current (AC) load. The BOS can also include storage devices, such as batteries, so PV-generated electricity can be used during cloudy days or at night.