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Discussion Starter #1 (Edited)
The US NHTSA says "rollovers accounted for nearly 35% of all deaths from passenger vehicle crashes". In the UK this percentage should be around 27% because of higher seat belt use*. Here are short animations explaining how rollovers happen.

Many people here probably already know that EVs have a lower center of gravity than ICE cars if the battery is close to the floor which reduces rollover risk. But this advantage of EVs is not mentioned enough. Even the EU NCAP doesn't mention anything about rollover risk. Here is an example of their Nissan Leaf page.

So I created this small list comparing a few cars. SUVs score badly which is ironic because some people prefer them because they appear safer. If everything else was the same you would be 42% more likely to die in a Kia Sportage than in a Nissan Leaf because of high rollover risk.

There is a 57m long, very good documentary about the SUV rollover scandal in the US. Click here(4*) to watch it. It explains how NHTSA sided with car companies instead saving lives and how Ford knew about the problem but preferred paying off settlements after people died and lobbyists after there was a congressional hearing. The documentary says 2000 per year people die in the US because of SUV rollovers.

If Tesla Model X and Model 3 score 7.5%, both will be much safer than any comparable car in their class in terms of rollover risk.

Rollover Risk:
5.7% Tesla Model S
8% [Estimation for BMW i3***]
9.3% Chevrolet Volt
9.3% BMW 5 Series
9.5% BMW 3 Series (8.th**)
10.5% Mercedes-Benz C-Class (13.th**)
10.9% Nissan Leaf
12.1% Volkswagen Golf (5.th**)
14.3% Ford Fiesta (best selling car in the UK**)
14.7% Mitsubishi i-MiEV
15.1% Nissan Juke SUV (11.th)
15.5% Kia Sportage (best selling SUV in the UK)
17.4% Ford Explorer SUV (best selling SUV in the world) (5*)
22.8% Ford F-150 pickup truck
23.7% Ford F-250 pickup truck


*Seat belt use is 95% in the UK% and 84% in the US. Seat belts save lives in 69% of rollovers. Therefore in the UK the rollover fatality rate should be 35-(95-84)*0.69= 27.41% rounded to 27%.

** Link to best selling cars in the UK in 2013

*** Estimation is based on BMW i3's low center of gravity of 18.5 inches from the ground. While this is not as good as the 17.5 inches of the Model S, it is better than the 19.6 inches of the BMW 3 Series.

(4*) There is no copyright issue with this link. The same video is also embedded on the media production company's website here.

(5*) This particular car is involved in the SUV rollover scandal in the US. You can watch the 57m documentary mentioned above.
 

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Interesting stuff.
Possibly not so much emphasis on that here as the risk of fatality from roll overs is strongly linked to seatbelt use (69% were not wearing from your link above). The usage in the UK is much higher. Three times as many don't wear them in the USA (84% vs 95%).

I've been in a roll over and wasn't wearing a seat belt - a long time ago in a very old car (no rear belts). I got bounced around. Had I been thrown out, I probably wouldn't be here. The people in the front, who had belts, were pretty well untouched. I got a hospital visit.
Wear those seat belts!

Seatbelt use in UK is 95% (2009 figures)
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/8900/seat-belt-rates.pdf
In USA 84%
http://en.wikipedia.org/wiki/Seat_belt_use_rates_in_the_United_States
 
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Discussion Starter #5 (Edited)
MetalHead, I agree. I have now added more information to the opening message. Higher seat belt use would prevent fatalities in 69% of cases for the additional 11% who wear seat belts.

My theory on why NCAP doesn't include rollover risk is because all cars score close to each other in the same class. For all SUV's it is 14-16%. For all sedans it is 9-11%. Smaller cars 10-12%. However with electric cars things have now changed dramatically. On the NHTSA website I can not find any other car that scores better than the Model S. The Model X could score 7.5% or even lower and it would be less than half risky as any other SUV.
 

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Discussion Starter #7 (Edited)
There is no data on NHTSA about the rollover risk of the i3 but its center of gravity is 18.5 inches from the ground. This is very low. The Model S is 17.5 inches. The BMW 3 series is 20 inches. Therefore the i3 should score around 8%. I'm also taking into account that the Model S is a wider car which contributes to its low score. If that estimation is accurate then both the Nissan Leaf and the i3 score better than most of the best selling cars in the UK.

Edit:
To be more precise, the i3 would score better than any of the best selling 20 cars in the UK. The Leaf would be better than most best selling cars. The Model S scores better than the i3 or any other car that was tested. I added Mercedes C class to the list. It is among top 20 best selling cars.
 

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Discussion Starter #8
Possibly not so much emphasis on that here as the risk of fatality from roll overs is strongly linked to seatbelt use (69% were not wearing from your link above).
Apparently there was a big scandal in the US about SUV rollovers. I have now added a link to a long documentary. It explains how this was a big issue in the US for over a decade. The Ford Explorer was also involved in the scandal. I added it to the list. Unsurprisingly it is the worst scoring car. It has more than 3 times the rollover risk of a Model S.
 

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Even the EU NCAP doesn't mention anything about rollover risk. Here is an example of their Nissan Leaf page
What is quite surprising is how much worse the driver fairs compared to the passenger in a Leaf.

Initially I just put this down to the steering wheel. But looking at similar sized cars, driver's safety is normally broadly the same in both front seats, so maybe not.

The test was performed on a RHD car, not sure if a LHD car would be different. I guess it depends on if they needed to reposition lots of components. I know a lot of "designed for LHD" cars have all sorts of compromises in the engine bay (extra hoses, inaccessible fuse boxes, offset pedal boxes, even strange mechanical linkages to the master cylinder..)
 

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Rollover risk in Europe commonly tested via Moose / Elk test which is rather more practical and less theoretical than centre of gravity. Moose / Elk test would also reflect suspension characteristics and aids like ESP which are probably more common in Europe.
 

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Aside from the safety of having a low center-of-gravity, it also makes the driving experience much more-enjoyable. I can take some bends in a 50 mph highway at 50 mph where I feel it necessary to slow down in my Chrysler Sebring. Add the regenerative-assisted brakes to the mix (braking in the Volt is far more-responsive than in the Sebring), and it makes for a more-enjoyable drive.
 

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Aside from the safety of having a low center-of-gravity, it also makes the driving experience much more-enjoyable. I can take some bends in a 50 mph highway at 50 mph where I feel it necessary to slow down in my Chrysler Sebring. Add the regenerative-assisted brakes to the mix (braking in the Volt is far more-responsive than in the Sebring), and it makes for a more-enjoyable drive.
My Elise has a higher CoG than the Tesla, I can assure you the Lotus goes round corners better ;) It also brakes better despite lack of regen (or power brakes, or even ABS for that matter).

What it lacks from a performance POV is the immediacy of throttle response the Tesla's torque brings to the party.

(+obviously all the luxury stuff like a roof that doesn't leak :D)
 

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My Elise has a higher CoG than the Tesla, I can assure you the Lotus goes round corners better ;) It also brakes better despite lack of regen (or power brakes, or even ABS for that matter).
Sadly, I have no first-hand Elise driving experience. I speak only of my experience in driving an '85 Cavalier, a '99 Galant, an '05 Sebring, and a '12 Volt.
 

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Discussion Starter #15 (Edited)
Rollover risk in Europe commonly tested via Moose / Elk test which is rather more practical and less theoretical than centre of gravity.
I disagree with that statement. Rollover risk is important after an impact when two or four wheels don't touch the ground anymore. Electronic stability control is effective only while all wheels touch the ground which is not the case during an accident. This is mainly a marketing strategy by SUV manufacturers to make their rollover risk appear less than it is. I highly recommend watching the documentary I linked in the opening message. After you hit the kerb and the car goes flying, electronic stability control is not going to help you in any way.
 

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I disagree with that statement. Rollover risk is important after an impact when two or four wheels don't touch the ground anymore. Electronic stability control is effective only while all wheels touch the ground which is not the case during an accident. This is mainly a marketing strategy by SUV manufacturers to make their rollover risk appear less than it is. I highly recommend watching the documentary I linked in the opening message. After you hit the kerb and the car goes flying, electronic stability control is not going to help you in any way.
But ESP can stop you getting to the point where the wheels leave the ground in a sudden manoeuvre. And when did the topic change to SUVs? With one obvious exception behaviour of SUVs isn't too relavent to an EV forum.
 

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Discussion Starter #17
SUVs isn't too relavent to an EV forum.
They are. Here is how: Many car buyers buy SUVs because they think SUVs will be safer. This couldn't be further from the truth. In the opening message I listed some of the best selling SUVs and pickup trucks. For example the Ford Explorer and the Ford F150 are both death traps. Neither is safe at all because of the high rollover risk. If safety is your concern you should buy an EV because they have much less rollover risk.
 

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They are. Here is how: Many car buyers buy SUVs because they think SUVs will be safer. This couldn't be further from the truth. In the opening message I listed some of the best selling SUVs and pickup trucks. For example the Ford Explorer and the Ford F150 are both death traps. Neither is safe at all because of the high rollover risk. If safety is your concern you should buy an EV because they have much less rollover risk.
Strong language, but given that neither is sold in Europe not too much of a concern to most members here.
 

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They are. Here is how: Many car buyers buy SUVs because they think SUVs will be safer. This couldn't be further from the truth. In the opening message I listed some of the best selling SUVs and pickup trucks. For example the Ford Explorer and the Ford F150 are both death traps. Neither is safe at all because of the high rollover risk. If safety is your concern you should buy an EV because they have much less rollover risk.
If safety is your main concern, buy a Merc. S Class in "Guard" trim, and always sit in the back ;)

To blanket EV's as being safer isn't fair either, a Leaf is probably LESS safe than an ICE Ford Focus. Once you get to a point where the CoG is unlikely to cause a car to roll over at sensible speeds, side and frontal impact ratings become more important.
 
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