Isn’t This a Coal Fired Car?
In the first post, I introduced my first basic idea around EVs — that the electric energy medium is best matched to motion. But this still leaves the question of where the electricity comes from wide open! While the tailpipe CO2 emissions on an EV are 0.0 g/km, of course there are emissions in the energy supply pipeline somewhere. And also in the lifecycle if the vehicle.
There is tons of writing on this topic online, and I scoured much of it my quest to try and understand the true impact (or not) of EVs. Here are a few pieces I found helpful. The Union of Concerned Scientists did a lifecycle analysis of EVs from ‘cradle to grave’, and found that they were far less harmful in terms of global warming, and getting better.
Over their lifetime, battery electric vehicles produce far less global warming pollution than their gasoline counterparts — and they’re getting cleaner.
Specifically on the question of how emissions intensive kms (or miles!) are in EVs, I found the analysis presented by Shrink That Footprint useful. The bottom line they present on the emissions intensity of EVs is that it depends, on where you live.
The analysis quite helpfully boiled things down to the ‘emissions equivalent petrol car’ for a number of cars.
What this tell us is that where we live, in Australia, you would need to have a car that gets a modest (‘average’) 26 miles per gallon (MPG_US) in order to be equivalent to an EVs average emissions from the various generating plans, hydro dams, and other facilities that make up the Australian power system. In the parlance of many here in Australia (and around the world), this means you’ll need to get roughly 9.0 L/100km to be equivalent to an EV based on Australia’s national power supply mix. If your internal combustion engine (ICE) vehicle gets 7.0 L/100km in Australia, you’re doing better than an EV. If you get 12.0 L/100km, you’re doing worse.
If you live in the USA, the analysis tells us you need to get a more thrifty 40 MPG_US (approx 5.8 L/100km) to be as efficient as an EV based on the national power mix there. (There is a great deal of variation by state in the USA.) In Canada (also lots of variation between provinces), its 87 MPG_US (2.7 L/100km). And in France (nukes!), you need to get a whopping 123 MPG_US (1.9 L/100km) to be as equivalent. Not even motorcycles come close to this efficiency mark.
I’m sure that these numbers can be contested, but I draw two points from them. (1) that there’s a great deal of variation between countries and their national power systems in terms of comparing EVs to ICE vehicles. And (2) that it appears that EVs are vastly more efficient compared to their ICE counterparts in terms of emissions. This is echoed by the Union of Concerned Scientists analysis.
This says nothing for the fact that the emissions intensity of national energy systems is generally decreasing (improving) as time goes on. (With the notable exception of Japan, who’s system of nuclear reactors remains largely deactivated as of March 2017). It also says nothing of the apparent fact that the refinement of petrol required to drive a certain distance requires a significant fraction of the electricity that is required for an EV to drive the same distance. In fact, it may take more electricity just to refine the petrol than to just drive the same distance in an EV. But more on that in a future post.
GD
