Car Question #19: why do electric vehicles have to look so silly?
Thursday, 12 October 2017
OPINION: If you're ambivalent about electric vehicles (EVs), odds-on it's down to one of two things: range anxiety or the fact they always seem to look a bit silly. Or perhaps both.
To many, electric vehicles are a turn-off because they lack a certain visual dignity. But are there good reasons for EVs to look like transportation pods from the planet Smorth?
Yes, of course. But not all are entirely scientific.
The most obvious one is aerodynamic efficiency. EVs are all about extracting the maximum distance from the limited battery power available, so it makes complete sense to have a slippery body shape.
**READ MORE:
* All-new Nissan Leaf revealed
* Why are there so many white cars?
* How do I get that new-car smell?**
Aerodynamics really ony became a thing for cars in the 1930s, and the work of German brainbox Wunibald Kamm from that era is still very influential today.
The so-called 'Kamm tail' combines long, smooth body contours with an abruptly cut-off tail. The best-known Kamm-tail car is also one of the most recognisable production-car shapes of modern times: the Toyota Prius. Which did not start out as an EV, but its electrified hybrid technology did help send the automotive industry down that path two decades ago.
That's why so many eco-friendly cars have looked so much like the Prius over the years. It's a very clean profile.
Automotive aerodynamics are generally measured by something called drag coefficient, represented by a 'Cd' number. As a point of reference, a modern family car might be in the 0.30-0.35 range. Something quite brick-like, such as a Ford Territory SUV, is more like 0.38.
The latest Prius is considered extremely smooth for a series-production car, with a figure of 0.24. Even the previous (taxi, anybody?) model was 0.25. The new Hyundai Ioniq EV, which looks very Prius-like, is also 0.24. These are very impressive numbers.
Simple, really. A silly shape equals smooth windflow. End of story? Not quite.
The thing about the Prius and its ilk looking so idiosyncratic is that silly body shapes have become synonymous with cutting-edge eco-automobiles, which has in turn made them handy marketing tools for makers of EVs. While weird styling might turn off the EV-undecided, it'll certainly attract the early adopters who want to make a statement.
So while many plug-in hybrid EVs are simply standard cars with extra batteries and a socket (think Mitsubishi Outlander PHEV), the trend for pure-EVs that run solely on battery power has been standalone/super-weird styling.
The Nissan Leaf is perhaps the prime example. It looks extremely silly but it's only moderately slippery by modern standards, with a Cd of 0.28. That's still really good, but also inferior to a Mazda3 hatchback (0.26), Mercedes-Benz C-class (which actually equals the eco-champs with a figure of 0.24) or Audi A4, which achieves a remarkable 0.23.
Or consider the BMW i3 EV, which is super-strange looking but only manages a Cd of 0.29.
Indeed, modern aerodynamic design allows carmakers to produce very slippery shapes that are still quite classic and elegant. Tesla's Model S sedan is 0.24 and the forthcoming Model 3 is claimed to achieve 0.23 (the original goal was 0.21, which would have been astonishing). Even the next-generation Leaf looks a lot more sporty and conventional than the current model.
As EV technology becomes more mainstream and carmakers start to design new generations of cars to suit a variety of powertrain options, expect pure-electric cars to become less silly looking. Or at least a lot less self-conscious.
The humble Volkswagen Golf has a Cd of just 0.27 even in standard form. Little wonder that the just-launched e-Golf, which is a pure-electric model, uses exactly the same body shape.