A network includes vehicle(s) having a battery pack and vehicle telematics unit (VTU), and a server. A server in communication with the VTUs and remote client device(s) is programmed to receive vehicle information from the VTU, including an energy throughput value defined by charging power delivered to the battery pack during an active charging event. The server receives utility information and a load adjustment request from the remote client device, including a power interrupt permission status describing whether interruption of power by a host of the client device is permitted. Charging control signals are transmitted in response to the load adjustment request to enable or postpone the charging event. Energy throughput is recorded over multiple active charging events, which are then combined or aggregated. Output data, e.g., a bill or report describing the aggregated energy throughput values, may be generated by the server. A method and server are also disclosed.