This was one of the major questions burning in my mind as I was doing research for The Manhattan Project of 2009.

If we took every gasoline-powered car, truck, and SUV and replaced their powertrain with an electric powertrain, how much electricity would it take to totally replace gasoline?

This is easy to figure out.

In the U.S., we use 142 billion gallons of gasoline per year. Each gallon of gasoline contains about 36.6 kilowatt-hours of energy. So, the total energy consumed by gasoline-powered vehicles is:

142,000,000,000 x 36.6 kilowatt-hours = 5,197,200,000,000 kilowatt-hours

That is, the energy in all the gasoline consumed is about 5,200 billion kilowatt-hours.

So is that how much electricity we need? No! It turns out that electric vehicles are far more energy efficient! A gasoline-powered vehicle does good to average 15% energy efficiency. I know this from taking actual measurements while doing research for my first book. A plug-in electric car, however, can easily maintain 60% energy efficiency. Since the electric car is 4 times as efficient, it only needs 1/4 as much energy to go a mile. That means we can divide the total energy used by a gasoline-powered car to see how much electricity it would need to go the same distance.

5,200 billion kilowatt-hours / 4 = 1,300 billion kilowatt-hours

Here it is. This is how much electricity we will need in order to replace gasoline.

Let’s say we want to get this electricity from a renewable source. How does this much electricity compare to, say, wind energy? For this, we take a look at the estimated wind energy potential for the top 5 states1:

North Dakota 1,210 billion kilowatt-hours
Texas 1,190
Kansas 1,070
South Dakota 1,030
Montana 1.020

As you can see, gasoline could be almost totally replaced by the wind energy of North Dakota by itself.

The coming switch from gasoline to electricity is not lost on the big utility companies. They see electric vehicles as a major new market for electricity, and especially a market that will consume electricity mostly overnight, when the utilities have a lot of excess capacity.

In the late 90’s, Southern California Edison ran a fleet of 320 electric Toyota RAV4’s from 1997 to 2002, racking up 7 million miles in evaluating the potential of electric vehicles. The result: they were quite surprised at how well they worked, and how reliable they were. One of their major concerns was battery life; the tests showed conclusively that the vehicles’ NiMH batteries could provide 130,000 to 150,000 of reliable service.

More recently, SoCal Edison and Pacific Gas & Electric are partnering with Mitsubishi to test Mitsubishi’s i MiEV electric cars in their fleets. In addition to generally promoting electric cars, the companies are hoping to learn how to develop their infrastructure to better accommodate electric cars.


1Source: An Assesment of the Available Windy Land Area and Wind Energy Potential in the Contiguous United States, Pacific Northwest Laboratory, 1991.