Arguments around sustainable transport get more complicated the closer you look. Just comparing tailpipe emissions is not enough, and neither is “well to wheel”, which considers the whole path of energy generation behind a vehicle. But when you bring vehicle production and disposal across the entire lifecycle into play, the phrase “opening a can of worms” is an understatement. It’s more like a pit. Of vipers.
Electrification is considered the leading way to reduce transportation emissions. A battery-electric vehicle (BEV) does have zero tailpipe emissions compared to internal combustion engines (ICE). It will also produce less brake dust due to regenerative braking. There may be marginally more tire wear, due to BEVs generally being heavier, but those particulates tend to be larger than the NOx particles from ICE so less problematic for health, and the effects of this have been hugely overstated anyway.
Electrification reduces emissions, but if you want true sustainable transport you need to consider … [+]
If you factor in where the power for BEVs comes from, things get a bit more complicated. The emissions from electricity generation vary a lot across countries and even within countries, depending on the balance of fossil fuel, renewable and nuclear energy used by the respective national grids. However, as I have argued in the past, even with a dirty grid like Australia’s, EVs still produce less CO2 than a highly efficient hybrid ICE.
Of course, if you’re going to factor in the emissions from electricity generation, you also need to consider the electricity and pollution caused during the production and refining of fossil fuels, which Auke Hoekstra of Eindhoven University of Technology has estimated adds up to 30% to what comes out of the tailpipe of an ICE vehicle. As I argued in my previous article, that makes a Toyota Prius emit more CO2 than a BEV whatever the grid.
Volvo has famously compared the lifetime carbon footprint of BEV and ICE versions of its XC40 SUV.
The next level to consider is vehicle production. BEV manufacturers do have to admit that building their cars creates more initial pollution than for ICE, mostly due to the battery. Volvo has been quite candid about the carbon footprint of its BEVs compared to its ICE cars, using its XC40 SUV as the example, and its figures have been used as a stick to beat electrification with by the anti-environmentalist lobby ever since. However, if you look at total lifecycle emissions more generally, as the research from the International Council on Clean Transport I cited in a previous article shows, BEVs still cause lower lifetime emissions than ICE, wherever they have been made and fueled – even China and India.
Production is more complicated than just CO2, though, and this is where that pit of vipers becomes truly poisonous. Vehicle supply chains are tortuously complex and counting the contributions of each individual component requires much better tracking than is currently available. How was the steel in each screw smelted? Where did all the plastics come from? Are there any animal products used? Where were all the minerals in the BEV batteries obtained from, and how were they mined? This is not just a retrospective endeavor to account for total carbon footprint but will also be essential to know at the end of a vehicle’s life, so it can be broken down and recycled more intelligently. The long-term dream is a circular economy, where the vast majority of materials end up being used again in newly manufactured products.
BMW is working with PLASTIX to recycle the plastic from discarded fishing nets.
Beyond electrification, there is a lot that can be done to make every component used in a vehicle’s manufacture as sustainable as possible. BMW, for example, has recently announced how it will be using plastics from recycled fishing nets and ropes to make trim parts such as floor mats for its cars. Lots of products are already being made from recycled plastic bottles, with a whole ecosystem for collecting these after use and then producing new plastic raw materials from them. The fishing nets are a relatively new area, although Polestar has been using them for a few years. Traditionally, when fishing nets and ropes reach the end of their useful lives, fishermen just cut them loose and dump them in the ocean. The company PLASTIX that BMW is working with is incentivizing the fishermen to bring these used nets and ropes back onshore by offering to pay for them, after which they are recycled into plastic pellets that can be used for manufacturing new components.
Volvo is another company that, along with its sister brand Polestar, is focusing heavily on understanding its supply chain and how to use recycled materials as much as possible. Where BMW has its i Vision Circular – a concept car made entirely of “secondary” recycled materials – Polestar has the Precept and Volvo went leather-free last year. Tesla stopped using leather in 2019, although it did meet criticism for doing so. These are just a few examples of how companies are realizing that the entire supply chain needs to become decarbonized, sustainable, and based on secondary materials as much as possible. It’s likely that this will become a huge industry over the coming years.
Car manufacturing supply chains are extremely complicated and global in reach.
Key to the success of this strategy will be centralized knowledge of supply chains, including where the materials in components come from, what they are, how they were made and how much energy was used in their making. Another program BMW is involved with is a supply chain data ecosystem called Catena-X. This will require huge buy-in from suppliers and manufacturers, however, who will need to enter the information or work to make their existing materials databases compatible. It’s not likely to be an easy task but will be an essential step towards circularity. Knowing which components were used in a vehicle that has reached the end of its useful life will make recycling those components, either by reusing them directly or recycling the materials, much easier.
Just to further deepen that viper pit, however, there’s another element that needs considering. One of the major arguments against BEVs is the extensive use of cobalt in their batteries. A lot of the global supply of this mineral comes from the Democratic Republic of Congo (DRC), where a lot of “artisanal” child labor is used in its mining. Although there are battery chemistries such as Lithium Iron Phosphate (LFP) with no cobalt, and cobalt can be sourced from countries with better labor practices such as Australia or Canada, this is a valid area of concern. The DRC can be forced to improve its practices, which organizations such as the Fair Cobalt Alliance are trying to do, but it’s hardly the only place in the world where workers are exploited including children. Just as we need to decarbonize the whole supply chain towards greater sustainability, the ethics of that supply chain needs to be considered as well. Electrification is just one, albeit important, piece of that puzzle.
