Electric Vehicles: A Win-Win-Win for California

Electric Vehicles: A Win-Win-Win for California

AC Propulsion, Inc.
January 25, 2001

What cleans the air, improves the operation of the electric power grid, and saves money for consumers? Its the electric vehicle.

Surprised? You should be. After all, auto executive and the automotive press have been telling us for years that battery-powered cars cost too much and don't work.

Among a growing number of academics and engineers, a more favorable picture is emerging that shows electric vehicles not as a burden on the grid, but as an integral part of the grid. The "eureka" idea, the light bulb going on, the discontinuity, is that transportation and power generation need not exist as separate and distinct functions. With the advent of electric vehicles, the same equipment that propels the car can generate power for the grid. The vehicle serves two functions. An electric vehicle charges its batteries during off-peak hours by taking power from the grid, but it can also feed power back into the grid when demand is highest. If that power is available at the right time and in the right amounts it can have very beneficial effects.

One barrier to this way of thinking is the terminology used to describe power. With a car, power is horsepower. With electricity it is watts, or kilowatts (1,000 watts), or megawatts (1,000,000 watts). They are different names for the same thing. It takes 1.34 hp to equal 1 kW so a 134 horsepower car has 100 kW under the hood, even if it has a gasoline engine. When you think about cars as kilowatts, the idea of tying them into the grid doesn't seem so far-fetched.

At this time of year, California needs about 30,000 megawatts of electric power, and during peak demand periods just a few hundred megawatts can make a big difference. California has about 24 million cars on the road. With 100 kW from each car, the vehicle fleet has 2.4 million megawatts or 80 times the total power used by the whole state. Unfortunately, conventional cars can't generate electricity, so we have not solved the electric power crisis, but we have shown that the vehicle fleet has plenty of power. If just a fraction of the fleet could feed power to the grid, we would gain a new and useful source of power capacity.

One problem running the grid is balancing supply and demand. There is no electricity storage in the grid, so each light turned on requires a little more power generation, each light turned off a little less. Total power demand is relatively predictable over a day, but at the margin it takes a lot of fine tuning to keep the system operating smoothly. The California Independent System Operator (Cal ISO) keeps the California grid balanced. They apply a number of techniques including the use of so-called regulation power. They use regulation power to smooth short-term fluctuations and maintain the fundamental 60 cycle grid frequency.

Electric vehicles can supply regulation power while they are plugged in to conventional charging outlets. They can produce power by discharging their batteries into the grid, and absorb power by recharging from the grid. Because EVs can respond so quickly to changing demands, they are ideally suited for grid regulation. EVs could provide regulation power whenever they are plugged in; as much as 22 or 23 hours a day. Once we have many EVs, say 100,000 or more, their sheer number will provide a statistically reliable source for a significant part of the total regulation power requirement.

Skeptics think we will never have 100,000 EVs because they cost too much. Over the short term EVs may cost more because they are built in low volume, but the grid support services they can provide are extremely valuable. Cal ISO spends about $1 billion (that is billion with a b) a year on regulation power alone. EVs can earn a piece of that $1 billion dollars for their owners. The value could amount to $10,000 per car per year, enough to trigger wild demand for EVs, without any cost to the public. In addition, a large new supply of regulation capacity would drive down the market price of regulation power, saving money for California electricity ratepayers.

Power regulation is not the only way electric-drive vehicles can provide grid support services. Hybrid and fuel cell EVs can contribute too, generating power cleanly and efficiently. The best automotive powertrains show the potential for power generation that is cleaner than small turbine or diesel generator sets. In the future, when electric, hybrid, and fuel cell vehicles start talking to the power grid via wireless internet connections, the potential for vehicle-to-grid power will even go beyond what we have talked about here. By harnessing this potential, California can realize the air quality benefits of electric vehicles, improve operation of the grid, and create value and motivation for EV ownership, a win-win-win situation.

CARB did not know about the potential for vehicle-to-grid power when they promulgated the ZEV mandate in 1990, but they did know that the future in California had to be different from the past. They knew that the conventional path would not be good enough. They were right in 1990, and they are right now. California should move forward with electric cars. The ZEV mandate seems to be necessary to drag the auto industry, kicking and screaming perhaps, along with us.