A Robust Mechanism to Dynamically Provide Grid Services with a Fleet of Plug-in Electric Vehicles

Plug-in Electric Vehicles (PEVs) are a rapidly developing technology that can help to reduce greenhouse gas emissions and our dependence on foreign oil. PEVs will also be an integral part of the future smart grid, due to two main features: First, PEV charging stations will most likely be available at home and at work, offering flexible charging options. Second, these vehicles will have the capability of transmitting electricity back to the grid, known as a vehicle-to-grid (V2G) system. These features allow PEV charging and discharging to be distributed among vehicles in order to benefit the consumer, who may profit from charging when electricity prices are relatively low and discharging when the electricity prices are higher. Moreover, a fleet of vehicles can be used to provide grid services for electric utilities. Utility companies may utilize PEVs as distributed energy storage devices that store surplus electricity generation to be transferred back to the grid in times of deficit, which will assist the integration of variable generation via renewable energy resources into the grid. However, along with these benefits come challenges and risks. For example, how will PEVs impact the stability of power grid? What type of market mechanism would be most efficient to organize this distributed trading? Are there new business and service industries that could be created to manage PEVs? Our proposed project aims to address these questions and challenges. In particular, we propose to construct an automated Demand Response (DR) mechanism for a fleet of PEVs that defines the role of electric vehicles in a smart grid. An aggregator, a new service unit, will communicate energy needs between a fleet and a utility, and regulate consumer electricity use to yield a beneficial transfer of energy. The DR aggregator uses a simple price equilibrium to instantly and automatically determine feasible energy exchange schedules for tens of thousands of vehicles as they plug-in to the grid, based only on a relatively small amount of aggregated historical data. Moreover, fleet charging of vehicles would be managed to stay within bounds placed by utilities. The charging and discharging schedules are robust to unexpected events, and reduce the consumer cost of charging a PEV. These generated schedules can result in a balance of electricity supply and demand and ensure that a new demand peak is not created, which are key features to maintaining the stability of the electricity grid.