What is sustainable? It turns out the answer is quite complicated. Take, for example, a conversation I had with a supplier at the Reuters Automotive Europe conference in Munich. The company specializes in software to optimize materials and design selection in electrified powertrains, the idea being to find the most effective starting point for system design and detail optimization.
An interesting point was raised. The company’s technology looks not only at the properties of materials and parts but also at things like their carbon impact – vital for the creation of overall vehicle LCAs. Great, you may think, if sustainability is the target just pick the material with the lowest impact in its manufacturing stage. Not so fast: what if an alternative material has a more carbon-intensive manufacturing process but enables greater efficiency from a motor? Do the lifetime savings over a vehicle’s use cancel out the greater initial carbon cost? Then there are all the usual considerations of price and supply chain stability to factor in. See what I mean about things being complicated?
Fortunately, there are plenty of new tools to help engineers strike these balances and keep track of the myriad interactions that contribute to a vehicle’s lifetime emissions.
But what about once a car is in use? There is much debate (with plenty of shouting on all sides) about whether EVs really are the silver bullet for the decarbonization of transportation. They are undeniably a very efficient way to use renewable energy and are zero emission at the point of use. However, a BEV, when put next to a comparable ICE car, has a much greater level of embedded carbon from its manufacturing process.
Take a scenario I was pondering recently. Small city cars are arguably the best application of EVs because they produce no air pollution (beyond tire particulates) and less noise pollution. But is, for example, Fiat’s 500e (42kWh pack) a better bet for lifetime emissions than the company’s 1.0-liter mild-hybrid in a city setting? Usefully, both have been assessed under Green NCAP’s European LCA methodology.
A quick scan of the UK classifieds looking for 10-year-old cars (a reasonable life expectancy for a small car) of max 1.0 liter revealed just over 1,600 for sale. Of these, 50% had less than 100,000km on the clock. At this mileage, the 500e racks up 19.6 tons of CO2 and the 1.0 gasoline 21.55 tons – a mere 1.95-ton difference. Over 20% of the cars had only covered around 60,000km, at which point the gasoline beats the electric by just over one ton of CO2. Surely this is an argument for small-capacity PHEVs with a range of maybe 25km and a 15kWh battery pack if the goal is overall CO2 emissions reduction?
Running the 500’s petite 1.0-liter ICE on E85 would knock a decent lump off the emissions and give a lower overall carbon cost. Or imagine if some of the R&D money being poured into BEV development were applied to upping the efficiency of small ICEs – the application of passive pre-chamber ignition systems detailed in the latest issue of APTi being one option. Could that swing the pendulum away from BEV in this particular case?
The point here is not to bash one approach in favor of another but merely to highlight that in the real world sustainability is complicated. Whether your remit is BEV, PHEV, ICE or H2, APTI is here to help unravel some of that complexity.
