Last week I started digging into electricity as part of my posts the climate crisis. Today’s post continues that by looking at the potential increases in the demand for electricity from moving transportation to electric vehicles (EVs). To start with, it is quite difficult to wrap one’s head around just how much we drive in the US. In one year there are about 3.25 trillion (yup trillion) vehicle miles. I have found it difficult to find a recent breakdown of that by vehicle type, but in 2016 about 9% of that was trucks (I will use 10% as a first approximation) and the rest passenger cars.
There are fewer than 2 million EVs on the road in the United States today, which is less than 1% penetration. So again as a first approximation I will simply assume that all the vehicle miles have yet to be converted from gasoline to electric. So what does that look like in the US? An EV gets somewhere between 2.5 and 5 miles per kWh (Model X versus Leaf). I will use 4 miles per kWh. Now putting it all together for passenger cars:
0.90 * 3.25 * 10^12 miles / (4 miles / kWh) = 0.73 * 10^12 kWh
To move all passenger car traffic in the US to EVs we need to come up with an additional 0.73 trillion kWh hours of electricity. To put this in perspective we currently produce about 4.18 trillion kWh of electricity annually in the US, so we are looking at roughly a 17% increase.
Keep in mind though this was just passenger cars. Coming up with an estimate for trucks is a bit harder as there really aren’t any production electric trucks yet, so YMMV (so to speak) with the following. Based on the specifications of the Volvo FL Electric Truck, I am estimating 1km or 0.62 miles per kWh
0.10 * 3.25 * 10^12 miles / (0.62 miles / kWh) = 0.52 * 10^12 kWh
That’s another 12% or so increase in the total required electricity generation.
So together we are looking at about a 30% increase in electricity demand to move all of our cars and trucks away from fossil fuels. Not impossible at all, but also not easy. Now please keep in mind that, though that today our electricity production is still over 50% from fossil fuels.
So that starts to give us a better handle of the true scale of the issue of getting away from emissions. And as we will see in an upcoming post, it doesn’t stop there, when we take into account electrifying building heating. Now to be clear, I am not at all suggesting all of this electricity for EVs needs to be centrally generated and distributed in the current model. Also, some EVs may use fuel cells. But it still paints a picture of the magnitude of the challenge.