Implementations of the present invention contemplate utilizing a communicative infrastructure represented by a telematics unit of an electric vehicle and a telematics service provider (TSP) communicatively coupled to the telematics unit to control an amount of power reserved for a charging event of the vehicle. Specifically, the TSP utilizes information provided by the telematics unit, electrical power utilities, and electrical power metering devices to determine the characteristics of electrical energy available for charging the vehicle. The TSP can utilize the characteristics of the available energy along with additional information, such as charging preferences established by a subscriber of the TSP and vehicle use schedules, to determine an amount of power to reserve for the charging event. The amount of power reserved for the charging event may be determined based on cost, greenhouse gas emissions, a combination thereof, and on other factors.