What about driving through high standing water. I know that we're taught to never drive through flood waters, but there have been many times that I've had to drive through high standing waters to get somewhere. It's bad enough on my Trans-Am that the air intake is down low, inviting hyrda-lock, but what would an electric car do if the motors or batteries became immersed?
On a related note, when railroads were transitioning from steam locomotives to diesel-electric locomotives in the 1950s, they quickly learned that in flooded areas, you want to use a steam locomotive instead of a diesel-electric locomotive!
You need to reread the article. EVs are different because they have different design constraints. As the article points out, an EV isn't just a convential vehicle with the IC engine ripped out. The closest one can come is to perform the same functional test on each type of vehicle such as driving them into a rigid barrier at a controlled speed, crash test dummies on-board. Of course, certain design principles do contribute to basic safety and some vehicle designs incorporate them to a lesser or greater extent; but, I don't think we should argue that we should only compare vehicles with equivalent crush zones or only vehicles with a passenger capsule design against each other. Luxury features are not primarily safety features so likewise a comparison of only vehicles in a given price range doesn't make sense either, particularly if some economy vehicles would prove to be safer than some luxury ones; in fact, one can point to some very expensive vehicles with very poor roll-over characteristics. Where you might have a point is that the level of challenge might meet the level of risk; for example, a vehicle with a top speed of 150 mph might have to meet a higher standard than one that can only reach 85 mph.
I often tell non-engineers that we tested something, but that doesn't mean it's good.
It means it passed the test we gave it, using what we used, when we tested it. It has a moderate predictive value. I have made a career troubleshooting designs that passed test and didn't work. Hell, at the aerospace companies I worked for (Martin and Raytheon) as often as not, when Test would find a failure of a product to meet specs, the product engineers would just change the specs to conform to test results.
Still, the specs here are how the car reacts to crashes, which apply to all vehicles. A Yugo isn't going to get 5 stars across the board like a Mercedes will. The Mercedes is undeniably safer. So is the Tesla. Without a doubt.
Does it transfer to smaller EVs? Probably the rollover does. Maybe the gas issue. The electrical problem is a real one, and I'm with you on that. Just because those lithium batteries are the same as those in your iPhone doesn't make them any safer. Look no further than the Boeing Dreamliner. QED.
anandy, it's true there are energy storage issues.
Leatherman tools, oscilloscopes, DVMs, guns, are examples of extremely useful products of which there are no universally perfect configurations.
Cars have been that way for a long time. Somehow, people have always wanted a sporty, economical, attractive, fast, four-wheel drive, comfortable, spacious, freight-friendly, 7 passenger two seater with a manual, automatic transmission, multi-fuel capability, iPod electronic dash that any teenager or housewife could self-service. There are inherent conflicts in that imaginary list, as you can see!
I've always told my friends who have never done a product design that all clients want someting that does everything for nothing, now. Easy peasey, right? If you are an engineer, you know exactly what I mean. THey don't get physics OR economics!
The Tesla, like my Honda Insight, isn't a vehicle for transporting sheet rock or plywood or casual off-roading. It has to be employed within its capability envelop. That envelop (moving ONE person from point A to point B, within town or on short interstate trips) covers a lot of US daily drivers, perhaps the majority. The incremental infrastructure to make this viable isn't that huge. I think the problem of charging is a red-herring. A Tesla, if I had one, would meet 95% of my transportation demands. Maybe 99. If I had the money to waste on one, I would have enough to rent a Tacoma pickup when I need one, which is annually.
These guys are on to something, I think. I think they'll push the lagging buzzards at Ford, GM, and the rest forward. These cars are selling like hotcakes, priced like Mercedes. THe Big 3 have been sitting idle, completely ignorant or dismissive of the market potential. (Think Apple versus Blackberry/RIM.)
Truely a misleading article tring to take a rating for the Tesla and tranferring that good rating to all EV vechiles.
1. The Telsa is not your normal EV car. It is an extreme luxury car replacement Think BMW so should be compared to such. It is very large in size for an EV so it benifits heavily from this size issue. This rating does very little to transfer to other EV's which are like Yugo's and would easily be crushed like a bug in a true accident. Their is a whole class of small enclosed EV's which are not even rated as standard cars, because they could not pass current auto standards.
2. As engineers we all know the results are only as good as the tests. These tests were written for gas vechiles developed to test for common failure modes fo gas vechiles. The rollover test came about after top heavy vechiles rollover became common, Rear crash test from the failure of Pinto et al to protect the fuel tank.
When testing an EV you cannot use the same standard, a common goverment mistake. EV's have their own set of failure modes that need tested sadly we will not know many of these until they become more widely accepted. One we do know and I cannot tell you if their is a test for, is battery rupture and latter meltdown by fire.
While the electric cars may be passing most of the NHTSA safety tests with flying colors, they still have some underlying problems that will make sure they do not become an entirely viable alternative anytime in the near future. For instance (and this is one of the most serious problems) they have serious shortage when it comes to power storage. The power can only last so long and its not like you can drive into a gas station for a recharge as you would with an ordinary car.
Chuck, Excellent post and interesting angle on Tesla's success. Certainly this is a company that is red hot in terms of perception and innovation> Safety isn't the only reason to buy an electric car but it definitely adds to the value.
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