It’s not that simple (and us morons know that), but you bring up a good point and it is the source of a lot of confusion. The truth is a little more complicated, but if you break it down it becomes easier to think about.
Now, you are correct in that electric cars are only zero emissions for the car itself, however, the cars actual emissions depend entirely on the methods used to generate power for the electric car in question.
In order to figure out what is better, we’d have to take all the miles driven by all the cars in the US and estimate the total hydrocarbon output (pollution).
Then average it out. Then we could create a metric for pollution per mile driven by the average combustion engine car. Basically, we do that in the average mpg statistics for ICE cars in the US, which is about 28mpg.
Then we’d need to do the same for electrics. We’d need to calculate the MPG equivalent with respect to pollution. That is, how many miles can an electric drive before it’s made the same amount of pollution as an ICE based on the power sources it get’s it’s energy from and create an equivalent.
Obviously, electrics themselves make zero emissions, so we’d have to look at the amount of energy that needed to be generated to drive an electric a certain number of miles then look at the sources of generation that make electricity for electric cars. Assuming that electrics will be in places that use power in the same proportions as the chart below, then it’s reasonably easy to figure out the amount of pollution created to drive an electric a certain number of miles.
Here we see the breakdown:
The question is, do these sources taken together when powering the average electric car make less pollution when compared equally to a car with an ICE?
Without getting into the specifics, I believe the answer is yes (less pollution), however, when looking at the whole world the answer is no in some countries. The answer in nations like China, India, South Africa and, surprisingly, Australia is no as electrics can only drive about 25 miles before the sources they get their power from make the same amount of pollution as the average ICE.
However, in other countries, the answer is a resounding yes, places like Brazil, Paraguay, Norway, Sweden and most of Europe.
The statistics I’ve seen basically take all the data and look at the data and give electrics a mile per gallon equivalent rating based on the electricity generation method.
In the US the average ICE gets close to 28mpg whereas the energy sources for electrics create the same amount of pollution as an ICE getting 40mpg (again, driven 40 miles before the sources they get power from make the same amount of pollution as an ICE). In India, it’s about 24mpg equivalent for an electric (one of the worst, and in Norway and Sweden it’s about 160mpg equivalent…So it varies quite a bit depending on the nations electrical sources.
So clearly you are 100% right, the issue is more complicated and there are definitely emissions associated with electrics, but they are still better than ICE’s in most nations in the world.
Now there are other factors I’m sure to be reminded of. The emissions to create electrics are higher, So, on day one, ICE’s start with an advantage and the electric has to “earn” the lead by driving and saving emissions over its usable life. Then there are potential emissions associated with destruction/ recycling. I don’t have figures for these, I just know electrics are higher emissions in the creation phase, I’m not sure how much higher, though I’ve read that from creation to destruction, they make less pollution.
The other thing to remember is that even if electrics and ICE’s were equal, one thing electrics do is move pollution from the cities they drive into the power plants which are typically aware of densely populated areas. This might be a big deal in cities like Shanghi in China, so even if electrics there make more polution than ICE’s they can move that polution out of the city.
Having said that. I don’t expect anyone here to just take my word for it. If you care, do some research, if you don’t, well, believe what you want to believe.
Anyway, hope that helps.