EV Carbon Parity
Every anti EV person seems hung up on terms like carbon neutrality and carbon footprint and carbon parity without ever seeming to actually research it and do the math. Often they just refer to several early studies that used incorrect assumptions about the way technology would progress as their gospel. Well, here is some real world math to maybe cover the gaps, in this case just showing how an EVs carbon footprint can achieve carbon parity vs a comparable gas car by 20,000 miles.
I’m using my 460 hp 2020 Tesla Model 3 stealth as an example vs a 480 hp 2020 BMW M3 (G80) 3.0 since they both have similar weight when fueled up (Tesla 4000 lbs, BMW 3850 lbs), hp, 0-60 acceleration (Tesla 3.0 seconds, BMW 4.0 seconds), top speed 162 vs 155, and both are 4 door 5 passenger sports sedans…and my wife has a 1998 M3 .
Pertinent details for CO2 footprint include: BMW prides itself on being green so will assume the BMW M3 manufacturing process creates the same amount of CO2 as does the Tesla minus the battery This is a bit flawed assumption because Tesla’s are highly vertical manufactured with much fewer parts and less transport of parts from 3rd party suppliers so inherently its vehicle manufacturing would be less fuel energy intensive but we will stick with the worst case assumption for this exercise. So, things being equal that just leaves the batteries. In 2019-2020 timeframe a Tesla battery packs mining, refining, and manufacturing produced 75 kg CO2 per kWh of battery capacity. My Model 3 has 75 kWh capacity. That pretty much covers the manufacturing impact raw data. The per mile impact is easy. The BMW M3 produces 248 gram CO2 per km (from their specs)…that is 399.4 grams per mile. The electricity my Tesla uses here in GA and FL averages 300 grams CO2 produced per kWh (much lower at night in North GA and higher at times in FL). Also, my Tesla gets 4 miles per kwh.
Now for the math. 75*75*2.2=12,375 lbs of CO2 produced in excess during the manufacture of the Tesla because of the batteries. At 4 miles per kwh, my Tesla only causes the production of (300/4)=75 grams CO2 per mile driven. So, at 20,000 miles in each car, the Tesla will have gifted the world 12,375+(75*20000/1000)*2.2= 15675 lbs CO2 and the BMW will have produced (399.4*20000/1000)*2.2=17573 lbs CO2
Now keep in mind that this CO2 load I’m using is still around half fossil fuel generated electricity…bit less than half in NW GA at night and bit more in SW FL. That will continue to improve over time as well. I also didn’t factor in the 3-6 lbs of CO2 produced in refining and transporting gasoline (Stanford study iirc) since, well, I was only showing how my car is already at carbon parity by 20,000 miles. Using all the nitty gritty data the car was actually at carbon parity at just over 14,000 miles. Sorry for all the 75 numbers in the math. Weird coincidence is all.
Oh, after a 400,000 mile lifetime, the gas car will have produced 351,472 lbs of CO2, The Tesla 66,000 lbs...but likely a lot less as the grid gets greener.