According to the concept of vehicle-to-grid (V2G). Electric vehicles can act as a mobile storage device and provide support to a grid based on intermittent and distributed energy resources (DER) but what is the basic requirement to enable an EV as a resource for the grid rather than a burden?
With V2G-technology, we turn parked electric vehicles – at home and at work – into power service providers. They can deliver flexibility by either charging or discharging based on demand and supply of the energy system. This results in a better integration of renewable energy resources and more stability to the electricity grid.
EVs must be equipped with bidirectional chargers to allow the flow of energy in both directions. In a V2G paradigm, charging of the EV batteries from the grid is enabled when there is a plenty of electric energy production, while power delivery from the EV batteries to the grid is exploited when there is a plenty of electric energy demand.
Regulation services are a likely first step for V2G because of high market value and minimal stress on the vehicle power storage system.
Currently, frequency regulation is achieved mainly by cycling large generators, which is costly and can be slow in terms of response time. Storage devices like batteries, pumped hydro and flywheels have shown promise with a faster response times.
Batteries are the most promising candidate for robust regulation of supply and demand which brings EVs into consideration. Fast C-rates of EV batteries makes V2G a promising alternative for frequency regulation. EVs can respond quickly to regulation signals, which could be controlled independently by each vehicle.
Distribution system operators (DSOs) are responsible for operating and maintaining the distribution grid without any interruptions. Sudden demand of electricity in certain distribution grids due to electric vehicles can lead to congestion in the network due to limited transfer capacity. However, through V2G capability, the EVs located in a specific area can help in congestion mitigation in those networks.
Although markets exist for these solutions, with clients who are willing to pay for V2G services, at this point there are so many complicating factors around the integration of EV batteries into the power grid that the scalability of the business model at this time is limited.
Reference- Wikipedia, New Motion, Armada Power