V2G, short for vehicle-to-grid, is the concept of a system where cars powered by electricity can take the power needed to make them run from the power grid and return unused power when the car is not in use. The term was created by AC Propulsion Inc. In the V2G system, the car would plug in to the grid and, when parked and unused, the power grid could pull extra electricity from the car's battery. This would help provide stable power to cities while also providing power to electric cars which would be more environmentally friendly than cars powered solely by gasoline or other fuels.
Power grids provide electricity to buildings, streetlights, and any other resource that needs it. To keep the system functioning smoothly, the power plants need to create just enough power to meet demands. The amount used and the amount created need to stay fairly balanced or problems can occur. If a large imbalance happens, the power grid could experiences surges and stop working.
Using V2G systems would allow power plants to pull from cars when they needed more electricity than expected, and use less or none when it is not needed. The trick would be to balance the distribution of power between cars in an entire city or state so that car owners still have power to drive their cars. This alternative would help cut down on the need for gas to power cars and could protect the environment. It would also slow down the use of oil, which is a nonrenewable resource that will not come back after it is all used up.
Three possible types of V2G systems are under consideration. The first is a car which uses fuel to provide power and helps provide extra power to generators during times of the day when the power grid is under the most stress. The second type of car is a plug-in and is hooked into the power grid. When power is needed, it is drawn from the car and during times when power is in less demand the car can recharge. The final type of V2G system uses a solar powered vehicle to charge its battery and then give any extra power to the power grid for use.
For the V2G system to work, it would require three parts. First, cars which supported the system would need to become common to create enough for supplying the system. Next, a control system would need to be in place so it could regulate when and where to draw or supply power. Finally, a system that could calculate whether or not it should draw power from a specific car at that time would be crucial. Otherwise, owners could find their cars not charged in the mornings when they need to drive to work.
Certain skeptics of the system have pointed out that using this type of system would cause the cars' batteries to stop working much faster. They also point out that at this time neither cars nor the power grid are equipped to handle a system like this. A major overhaul would be needed before V2G could become a reality.