Aug 15 2023

A Lifecycle Analysis of Electric Vehicles

This article is part of my informal series on EVs, sorting through the claims, reality, and propaganda. There are many complicated factors to sort through, but overall, in my opinion, most concerns about EVs are outdated or overblown. There are definitely locations and use scenarios that still favor ICE (internal combustion engine) vehicles (or at least hybrids) for now, but the battery and EV technology is still on the steep part of the curve, and infrastructure is being built. The percentage of the population for whom EVs make sense will slowly expand, until it’s the best choice for 95% or so. Over this same time period (about 20 years) we should also be decarbonizing our energy production. We can also be reducing dependence on individual cars by building mass transit, making more walkable living spaces, and eventually developing cars as a service (with self-driving cars). For trains and long haul trucking, hydrogen may eventually be the best bet. For short flight planes, electric vehicles are increasingly plausible, while long distance jet travel will need biofuels to keep their carbon footprint down.

After my recent articles on EVs, and companion discussions on the SGU, one of the questions that has been raised that I want to dive deeper into is this – are EVs still better than ICE vehicles even when we consider everything that goes into vehicle production? Spoiler – I think the consensus is that yes, EVs are still better. They have a lower total carbon footprint over the lifetime of use than ICE vehicles. But this is not a universal opinion. For example, I was pointed to this podcast in which the business man and physicist host claims: “Pushing an all-EV world is likely to increase CO2 emissions.”

What we are talking about here is a lifecycle analysis of EVs vs ICE vehicles (or hybrids). From the gleam in an auto-engineers eye, to the ultimate car scrap heap, how much carbon was released? Also, and perhaps more importantly from a critical thinking perspective – why do apparent experts disagree on the answer? Let me address the second question first – experts disagree to the extent that there is uncertainty in the numbers, and there are disagreements about how to do the analysis.

The big question is, what do we count in the lifecycle analysis? There are elements that are uncontroversial – sourcing raw material, manufacturing the vehicle, the efficiency of the vehicle itself, maintenance, operation, repair and replacement parts, and end-0f-life recycling and scrapping. But – how far afield do we go when including infrastructure costs? Do we count the cost of building an maintaining gas stations, or recharging stations? Do we count geopolitical conflicts in oil-rich but unstable nations? How many layers deep do we get in the supply chain? And, how do we make sure we are doing this fairly, counting everything on both sides with the same criteria? It’s not difficult to tweak the process to create different outcomes. Also, we can emphasize what we do know, or the unknowns. There are always assumptions and unknowns in any such complicated analysis, and if it fits your perspective you can spin this into the narrative.

In short, I don’t think there is any way to end debate on this issue, nor, arguably, should we. But we still have to make decisions given this uncertainty, and the default decision should not be to do nothing (which is also a decision). Rather we need to go with the preponderance of evidence in a risk-benefit analysis. (If this sound familiar it’s because this is how medical decision-making works.) So what does the best current data say?

Here is a representative analysis from the IEA (Internation Energy Agency). They find that the lifetime carbon footprint of EV vehicles, even with the worst-case scenario regarding mining battery materials, is about half that of a comparable ICE vehicle. Here is another analysis that breaks it down visually by source of carbon. They find that for EVs the “tonnes of carbon equivalent” is 39, 47 for hybrids, and 55 for ICE vehicles. Again, EVs win. In another study of light duty trucks, EVs had 64% lower emissions than their ICE equivalents.

There are also different ways to slice this data. Here is an interesting analysis (with a meta-analysis of multiple studies) that looks at the probability that EV will have lower lifetime CO2 emissions than a comparable ICE vehicle based on the mix of energy production (the overall carbon intensity of electricity production), then splits it out by country (covering Europe) and for gasoline vs diesel. They find that for every European country, there is a >50% probability of EVs being better than gasoline. For diesel most were still >50%, but a few with the highest carbon intensity energy grids dropped to <50%. So if you life in Latvia, diesel may be best (although not likely for long).

Another way to look at the data is this – EVs cost more carbon to manufacture than ICE vehicles, then emit less with use. So we can ask – how long or far do you have to drive an EV before its carbon footprint is less than a comparable ICE vehicle? The answer will depend on what kind of vehicle and battery, and the energy mix where the EV is being recharged. There are multiple analyses here, but overall the results show that with a completely green energy mix the break-even point for EVs is six months. With a fossil fuel intensive electricity source, that point is 5 years. That is about the range – 6 months to 5 years. Most cars and most locations are going to be somewhere in there. The average age of a car on the road is 11 years, and EVs are projected to have a longer lifespan than ICE vehicles (300k miles vs 200k miles). So for most people, they will be driving their EVs long after the carbon break-even point.

After looking at dozens of analyses and reviews, it seems there is a strong consensus that EVs have a lower lifetime carbon footprint that ICE vehicles. This is true right now for most cars and most locations, with an average break even point of a few years. But these numbers are not static, and they will depend in the future on the choices we make today. As battery technology improves, they get more efficient. Already there are batteries that get twice the distance out of the same raw materials as are in existing EVs, and they will likely start showing up in cars in 2026. Thing will only get better from there. New battery designs are also less dependent on the worst raw materials, like cobalt. Meanwhile, now that we are paying attention (hopefully) we need to secure supply lines that are green, efficient, geopolitically advantageous, and humane.

The big variable, of course, is our energy infrastructure. EVs are already advantageous right now, but their carbon advantage over ICE vehicles is largely tied to the carbon intensity of our electricity production. The assumption is we will be making our energy more and more green and phase out fossil fuels. In 20 years, therefore, we should have batteries and EVs that are much better than we have today, and our energy mix should also have a much smaller carbon intensity. Things should only get more favorable for EVs from here, and significantly so.


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