EV’s carbon footprint will decrease over time, report says
The automotive industry is actively moving away from internal combustion, and as electric vehicles have become increasingly popular, the number of skeptics have grown. A spectrum of concerns has been raised, ranging from uncertainty about the true sustainability of EV production to systemic labor issues in raw material mining. Others have questioned if electric propulsion is even the right way forward, lauding alternatives like hydrogen or e-fuels. There’s nothing wrong with being skeptical, especially when the planet’s climate is at stake, but scientists are saying electric power truly is the way forward.
It’s true that electric vehicle production is an environmentally taxing process, more so than producing a gasoline-powered vehicle at the moment. While the material gathering footprint is similar across propulsion styles, the manufacturing and assembly of EVs can be five times more polluting than building an ICE car. But studies show that this front-end carbon footprint can be offset quickly by simply driving the vehicle.
Using life-cycle-analysis procedures, a study conducted for the Fuels Institute, a non-advocacy research and social welfare organization, found that EV greenhouse gas emissions become less carbon intense than an ICE vehicle at just 19,000 miles in states with low-carbon electricity. This study includes the delivery of electricity to an EV as part of its overall emissions footprint, in addition to the emissions brought on by material sourcing and manufacturing, whereas ICE vehicles take on a higher footprint from the delivery of fuel as well as the process of combusting fuel. Painting a broader picture, the study also shows that a typical ICE vehicle will emit 66 tons of greenhouse gas emissions (GHG) over the course of 200,000 miles, while hybrid and battery electric vehicles account for 47 tons and 39 tons over the same mileage, respectively.
That doesn’t mean electric vehicles are inherently cleaner, however, given that a number of factors can greatly affect the lifetime carbon footprint of an EV. The overall mileage that a vehicle is driven remains especially effectual, given that GHG emissions of ICE vehicles grow by 56% between 100,000 and 200,000 miles while an EV’s GHG output only grows by 36% in the same mileage. Driving style is another major factor, with an intensive driving style degrading overall battery health and potentially adding an additional 14 tons of GHG emissions over the lifetime of an EV.
Most important is the carbon intensity of a region’s electricity. Areas like West Virginia with coal-driven electricity can actually result in a BEV having a larger lifetime carbon footprint as compared to an ICE vehicle. In the same vein, states like Maine with renewably sourced electricity will provide an especially limited lifetime carbon footprint for a BEV, emitting only 17 tons of GHG emissions over a 200,000-mile period. That’s 47 tons less than the average ICE vehicle will emit over the same mileage.
How long do batteries really last? Skeptics have argued that electric vehicles will be prone to costly battery replacements on a regular basis, going as far as to say that there isn’t enough raw materials or grid power for the rise of EVs. There is anecdotal evidence to support this claim, with early EV adopters bearing the brunt of costly battery replacements well before 200,000 miles. Auke Hoekstra, director of energy transition research at the Eindhoven University of Technology, says that these issues are undoubtedly present with inadequately cooled and poorly managed battery electric vehicles, but they aren’t indicative of true battery life.
Electric vehicles are naturally prone to battery degradation, but the process is rarely linear. In fact, data taken from hundreds of Tesla drivers showed an initially sharp drop in battery capacity (5%) over the first 62,000 miles before tapering off into a 1% loss for every additional 31,000 miles. Using this formula and the experience of Tesla owners with over 400,000 miles, Hoekstra says that lithium-ion EV batteries are not arbitrarily life limited, given that even these high-mileage Teslas retain 86% battery capacity. As battery heat management and charging technology develop, the rate of battery degradation is expected to diminish, too.
“All in all, the frequent assumption that the battery has to be replaced after 150,000 km is not correct and has no basis in science,” Hoekstra writes in a recent study. “It’s just an assumption that so far has not been challenged.”
The problems associated with EV production and lifetime emissions, however, are ones with a clear but laborious path ahead. Decarbonizing electricity will be an essential piece of the puzzle, from renewable electricity sourcing to battery recycling. As corporate fossil fuel use continues to be regulated, it’s unlikely that coal will remain a key source of electricity generation, and energy companies will be required to seek out renewable sources of electricity generation, further decarbonizing the EV experience. Volkswagen concurs, stating that EVs like its ID.3 are already significantly reductive to CO2 emissions with the current European electricity mix, and will continue this trend as the timeline for further decarbonization becomes apparent.
Battery recycling poses challenges of its own, as Hoekstra explains that melting down existing batteries to create recycled ones can be more polluting than initial manufacturing. That’s why direct cathode recycling technology—or any form of recycling that doesn’t require melting materials—is a more appropriate approach to closed-loop production cycles. Additionally, research by McKinsey and Company claims that the total demand for secondary energy storage systems is on the rise, with a predicted 7 gigawatt-hours (gWh) per year, of which 1 gWh is expected to be fulfilled by second-life automotive battery packs.
EV adoption will play a significant role in the advancement of these technologies, just as the advancement of these technologies will make EVs cheaper for consumers. Analysis by Ricardo PLC, an environmental consulting agency, claims that the electric crossover battery pack cost is expected to drop by more than 42% because of the reduced battery cell and assembly costs. As manufacturers source high-cost battery cells from a competitive supplier base, it’s also likely that battery supply costs will continue to be driven down. And as EV technology becomes more mainstream, analysts expect the overall cost of development to drop as well.
Altogether, the future of EV sustainability looks bright, with the majority of manufacturers focusing on decarbonizing the production process. Charging networks are known to be problematic, though federal funding continues to flow toward national network development. And EV R&D is happening at nearly every OEM, from Polestar to Maserati, meaning there should be more options for less money in the near future. There’s significant work still needed to improve the technology and overall market head, but it’s hard to argue with electric at this point.
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