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The Tesla has 6.1 inches of ground clearance, it looks like this underneath:
http://boronextrication.com/tag/hv/
If you look at the pictures, the battery is actually recessed between the frame railes by about an inch or so.

Now here's the underside of a Prius (5.7 inches ground clearance according to the numbers I could find on random forums?)
http://priuschat.com/threads/photos-taken-of-the-bottom-of-my-prius.68549/
The fuel tank is mounted so it is flush with the underbelly panels, about the same height as the Tesla's battery.

The big difference I see is that the Prius tank is way in the back, where anything that's going to be high enough to stab the car will probably stab it up front where the engine is, not the tank where all the energy is stored.

Your car is still pretty well screwed either way though.

My Prius does get 50mpg. Others get more. It depends on how you drive. Hint...flooring when the light goes green doesn't help.

I think changing the oil too often is something people do as a ritual to make themselves feel better. I don't think cylinder wear is particularly prominent among the causes of death for cars.

No, you've confused the instructions for first responders with the instructions for the dealerships doing post-crash repairs.
Per a post elsewhere:

The Volt service manual documents what should be done to inspect the high voltage systems following a collision in Volume 2, section 11, page 332. After a collision as severe as in the side-impact crash test, the battery pack should be removed from the vehicle.

Still it's a good thing NHTSA is looking into this (while not picking solely on GM). After the Toyota unintended acceleration issue the US auto safety regulators looked bad because they appeared to have not paid attention to the early warning signs, and that ended up being bad for the regulator, the regulatee, and the consumers. Even if this turns out to be a total non-problem, it will help debunk fear-mongering against EV technology. IMHO.

"At $6 a gallon, 20mpg is going to cost you $30,000.00 in gas over 100,000 miles. At 40mpg you save $15,000.00"

Very true. In less than 10 years the gas prices in the US have tripled, going from ~$1.33 in 2001 to $4/gal in 2011. At this rate we'll all be paying $9/gal by 2021. Don't think we'll get there? Did anyone really think we'd see $4/gal so fast? I don't know about you but my income didn't triple within the last 10 years.

I think we all need to start buying our cars with the idea that gas will be $9/gal very soon in the US because it's going to be here before you know it and our incomes are not going to match those prices. Screw the Explorer, get a Prius with a trailer hitch. Toyota will tell you no to sell more trucks but Prius owners say they've towed 2,000 lbs without problems.

I agree completely (AC here, forgot to sign in). However as was pointed out by myself and others, if you're plugging the car in it's not a hard problem to solve.

Still, your fuel economy shouldn't be dropping that much. Have you considered a block warmer? Here's one for the Prius. Setting your tires at sidewall pressure and covering the bottom grill (top grill on pre-2010 models) will also yield improvements.

Having used used streetcars/trams for a long time now, delays due to accidents are very rare. It's not really an issue. The situation might be different in other cities and countries, though, since the layout of the roads and other traffic conditions certainly play a role. I'm don't doubt the delay due to accidents is much higher for cars than for streetcars, though. (For overall delays I'm not ready to make such a bold statement.)

Comparing the efficiency of different modes of transportation is really difficult; and it's a bit odd (though not unusual) to use miles per gallon when trains and streetcars in western countries usually run on electricity. Finding emission equivalent information for public transport is hard because while passenger numbers are readily available, the average travelled distance isn't. The only solid information I could find in a couple of minutes is that the Berlin S-Bahn (urban light rail) has emissions of 72g CO2(equiv) per person and kilometre. The Berlin S-Bahn never struck me as particularly modern. The 2010 Prius (low emissions variant) allegedly emits 89g CO2 per kilometre, previous models emit 104g. Oh and I just found another reference, the German railway claims an average of 2.6l gasoline/100km per person for a half-filled long distance train, which translates to 58g CO2 per person and kilometre. (The typical average utilisation of long distance trains here seems to hover around 45%.)

References (two thirds German, I'm afraid):
Emissions in Berlin public transport: http://www.benjamin-hoff.de/article/3140.energieverbrauch-und-co2-emissionen-im-verkehr.html
Deutsche Bahn AG: http://www.s-bahn-berlin.de/aktuell/2010/024_klimaschutz.htm
Prius: http://priuschat.com/forums/gen-iii-2010-prius-main-forum/54240-2010-prius-92g-km-low-emissions-89g-km-version.html

My bad, it is only 44.8%
http://tinyurl.com/39mgjwt

Wrong. Please pay attention to the wording that I highlighted: normal driving. See the highlighting? You're comparing *peak efficiency* to *normal driving*. Check out the graph on the page that you linked. See how much efficiency varies? Beyond that, there's energy thrown away by braking and energy lost to idling. This (very roughly) halves the efficiency in non-hybrids from the peak.

The density of petrol varies around 750kg/m3 diesel around 820kg/m3.
So yes, there is a difference, but it is around 10%

If you had cited Wikipedia, you would have said that they're 18% different, giving a figure of 720kg/m^3 for gasoline and 850kg/m^3 for diesel. But the reality is that neither are right. There is no single density for gasoline or diesel because there is no single fuel called "gasoline" or "diesel". There are all different kinds of blends. They average about 15% difference.

And where the hell the 15% efficiency difference came from ?
I'm quoting your post, using your numbers.

Experience. To be less vague, when you've taken enough gasoline and diesel vehicles of the same model and same acceleration and compared their CO2 outputs and their density-adjusted fuel consumptions, you'll arrive at the same number (give or take ~5%).

For all of the below, I will use this and this for the BMW's stats. I will use this for the 2010 Prius's stats.

And yes, drag areas differs. Prius is smaller. It has also better aerodynamics (0.26 vs 0.27)

I guess I have to explain this one as well. Drag area *includes* the drag coefficient (Cd) (what you refer to as "better aerodynamics"). Drag area is the cross sectional area times the drag coefficient.

Drag areas are what matter, but they're rarely released (automakers prefer to release only the Cd, if that) -- although some release them, and other sites compute them. The BMW 320d EfficientDynamics actually has an official drag area -- 0.59m^2. The Prius does not. So we'll compare dimensions (ignoring length, as length is often a *good* thing).

Width: 68.7"(Prius), 71.5" (BMW)
Height: 58.7" (Prius), 55.4" (BMW)
Ground clearance: 5.5" (Prius), 5.1" (BMW)

If we treat them each as a square, minus the ground clearance, that's 3655 square inches for the Prius and 3,596 square inches for the BMW. So, not taking shape into account, but just dimensions, the BMW actually has a slightly lower cross section. It has a slightly higher drag coefficient. Overall, the drag areas should be approximately equal.

it has low RR eco tires

The Prius comes equipped with Yokohama AVID S33D tires. The BMW uses Michelin EnergySaver tires. Now, rolling drag coefficients are even harder to get than drag areas (and, FYI, are a grossly inaccurate measure anyway). But it's worth mentioning that the EnergySavers are the most efficient tire Michelin makes.

it is front wheel drive so there are (few %) less drive-train losses

True, but the effect is small, as you note.

it is almost 200 kg lighter than bmw (more than 10%)

Prius: 3042 lbs
BMW: 3296 lbs

200 pounds, perhaps, but not kg. Also note that part of the weight of the BMW is due to how heavy diesel engines are compared to gasoline, so this is, at least in part, something that should be credited as an advantage of hybrid tech over diesels, rather than a difference in the comparison vehicles themselves. Batteries are famously heavy, but the Prius pack is very small. Note that aero drag is well dominant in highway cycles over rolling.

it has brake energy

After I wrote that I found this web-site that explains how to use the device and what's going on. I still think that the dealer has some codes that are not OBDII certified that they use though. Incidentally, according to that web-site I linked to, the code machine is $200, but in this thread the person says the dealer is charging them $100 just to read the codes. Wow, expensive.

And again, I don't care what the efficiency is. I've already explained that. 65% of something is better than 100% of nothing. Besides all you did - again - was spout numbers. You didn't say those numbers came from that were used to derive your 65% value.

It's also worth mentioning that those numbers - 80/90/80 are like everything else you've posted. Gut feeling numbers with no reference. This is the third time I've brought that up. Numbers of no provenance, pulled from the aether. They are meaningless unless you can back them up.

My calculations show the Prius battery to hold 1.6 horsepower-hours. (Here is where I'm getting that value. Link1. Link2. See how easy that was? Try it sometime.) But again you fail to understand how it all works. The gas motor runs at a peak on a bell curve for efficiency regardless of road conditions. Cars without the CVT cannot do this. Since we're producing more horsepower at RPMs that are usually above and beyond the road conditions, they are stored. At whatever the efficiency happens to actually be. In deference to your inability to connect the dots, that makes them essentially free. A normal car would be running at a non-optimal rpm and simply discarding that gasoline's potential. The Prius does not.

And again (and again and again...), the battery never completely discharges or completely charges up. It's not like you can take that 1.6 horsepower/hour and use it exclusively. Both the electric motor and the gas motor can contribute to the drive train at the same time. Think of the battery as a short term buffer for energy, like a wound spring. Stop thinking of it as a fuel tank - it is not. That is what is getting you confused, I think. Either that or you've missed your meds.

Enuf trying to educate people that don't want to learn.

We are finally in agreement. I give up.

And be sure to transmit a copy of your resume to Toyota. They would probably pay you a cool million a year, what with your being smarter than their entire research division. They could fire them all and you could pull numbers out of space for them so they wouldn't make any more obvious mistakes. That would be awesome.

Do you have a source on that $100 number?

The $100 number came from a report I saw a while back but you don't have to take my word for it. You can safely disagree with the number because it depends on how you do the accounting. (disclosure - I'm a certified accountant as well as an industrial engineer) Any profit number for a particular vehicle will be an estimate since the auto companies don't break this stuff out enough to really know for sure. The largest number I've seen for profits per Prius is $1100/vehicle which I regard as optimistic because the R&D costs have been huge. Toyota admitted that the Prius lost money for the first 3-5 years after it was introduced which makes sense. Estimates vary on the profitability of the Prius but due to the added expense of the new technology it is widely considered to be at best marginally profitable and might even be losing money though I doubt it.

I tend to think Toyota is at least making a modest profit on the Prius (or was until recently) depending on how you do the accounting. I think if they were to fully apply all the costs of R&D to the Prius it probably is a breakeven proposition at best but Toyota is probably not fully allocating the R&D costs for hybrid technology. That's not unusual BTW - there are good reasons not to fully allocate costs. The Prius is a technology test bed and a great marketing tool for Toyota so there are benefits even if the vehicle itself isn't terribly profitable.

But they offer nothing. No cash back. No Hawiian trips. No 0% financing. The market demand for them is strong enough that when every other segment for them is dropping, the Prius continues to sell. Seems like a pretty strong indication of consumer demand to me ;)

The Toyota Prius was the 10th best selling vehicle by volume in the US from Jan-April of 2008. Nice sales figures but hardly indicative of overwhelming demand for hybrids. You will note that the Prius is the only hybrid vehicle on the list.

There's a post from Toyota at PriusChat.com. They're backing down. "Please let your members know that we offer a sincere apology to the DesktopNexus site and its users for any inconvenience or disruption this miscommunication may have caused."

According to
http://priuschat.com/forums/prius-main-forum/2419-max-speed-prius.html
people have gotten above 100 MPH in a Prius.

http://priuschat.com/forums/prius-main-forum/29373-100-000-mile-club-8.html

Lots of cars go over 100K.

I love the car, but neither of us has traction control

I must have a fluke then. On wet grass, I can't spin a tire. I feel it slip a tiny bit and the power immediatly drops. When I am done makeing a donught on the lawn, there is no divits to put back. There was not enough slippage to even find where I slipped. The grass just looks like someone gently drove over it. On ice and snow the response is the same. On Ice a traditional car can spin a tire and you can watch the speedo jump, often over 40 MPH while pulling away from a stop sign. You can't do that in my 02 Prius. It has a few very low power slips and back to rolling and I pull gently cross the intersection even when it done pedal to the metal.

Have you had yours on ice yet?

Acording to this forum, the 02 has it;
http://priuschat.com/forums/prius-main-forum/48000-prius-generation-i-vs-ii.html
"Older has traction-control, though you'll almost never trigger it. Stability didn't exist back then."

Contrary to the post, I trigger mine often. In wet weather, the thick white paint for the crosswalks are slippery. I often slip a little pulling away from lights and the instant power drop is obvious.

You know, it's just a rumor that he said that. The source of the report, Capitol Hill Blue, has a poor reputation for accuracy:

http://priuschat.com/index.php?showtopic=22180

http://www.dailykos.com/story/2005/12/9/143434/049

http://www.mccmedia.com/pipermail/brin-l/Week-of-M on-20060109/034824.html

The Prius' CVT seems to be mechanically simpler than a conventional automatic transmission. AFAIK there are no clutch plates, no torque converter and only 1 planetary gearset. I took some pictures of FWD and RWD automatic transmissions and put them up at http://priuschat.com/index.php?showtopic=30245&st= 0&p=403617&#entry403617. You can look at what the Prius' CVT/PSD (power split device) look like a little further down and at http://privatenrg.com/#Planetary_Gear. http://eahart.com/prius/psd/ has some more info and a simulator.

A Prius doesn't have an alternator, the inverter works to charge the 12V aux/accessory battery. It doesn't have a starter either, MG1 acts as the starter.

http://john1701a.com/prius/owners/jesse3.htm

This CNW story is such crap and its numbers make no sense. It's old news. I posted my critiques of CNW's old news before at http://www.my350z.com/forum/showthread.php?p=24945 37&highlight=crock#post2494537 and http://priuschat.com/index.php?showtopic=30444&st= 0&p=403215&#entry403215

Did you know that CNW claims that the Prius costs $325K to DISPOSE while they claim it cost $13K to make it? Did you that a VW Phaeton the sold for $64K to ~$100K incurs $2.5 MILLION in disposal costs? This is the type of crap that CNW spews out.

It also makes perfect (!) sense that they claim a Prius only lasts 100K miles when the HV battery is warranted for 10 years/150K miles in CA and a few other states. The Prius also has an excellent reliability record while the Hummer H2 has a terrible one... so therefore, the terrible one should last 300K miles. Right....

See http://www.usatoday.com/money/autos/2007-03-01-con sumer-report-list_x.htm for a ranking of reliability by manufacturer. Hummer is almost dead last.

Already happened ...

Yukon vs Accord head-on
Mustang side swipes an Explorer

And from the archives, the Gladwell article about SUVs: the psychology, history, and numbers:
http://www.gladwell.com/2004/2004_01_12_a_suv.html

Personally, I'm glad people drive SUVs. It's like the stupid-tax they call the lottery, but here it's like watching Darwinism in high-chairs action.

The new 2008 Prius is suppose to use Li-Ion batteries and get almost 100 mpg while getting to 60 in under 10 seconds

A glaring omission from the summary and from the article text:

The 0-60 time of the X1 is 2.8 seconds, according to the discussion on

http://priuschat.com/lofiversion/index.php/t15170. html

Here, here! Yay!

I'm already signed up for a 2006 Toyota Prius. It's the best choice in vehicles I have ever made. No guilt whatsoever.

http://www.priuschat.com/

Heres an interesting quote from a prius link given further in the conversation.

"I've gotten anywhere from 65 to over 100 miles per gallon," said Mr. Gremban, an engineer at CalCars, a small nonprofit group based in Palo Alto, Calif. He gets 40 to 45 miles per gallon driving his normal Prius.

link here

Gassing up only once a month would be nice ...

Goto some Prius enthusiast sites, or this specific page and you'll find there something called warp stealth.

If the battery is topped off, you're coasting, and you're not going uphill, the gas engine will just spin without being fed gasoline.

Plus, technology like regenerative braking, regenerative motion (charges battery when coasting), the fact that the gas engine's output is ALWAYS split 70% (drive wheels) / 30% feed electric motor/generator, this higher efficiency setup gives you the better mileage.

You're not using extra energy to charge the batteries. You're just using the excess gas engine energy to charge when driving at a constant speed. How much HP do you need to beat down wind-resistance?

I drive ~75mph and I routinely get 47mph on the highway - and I'm just breaking it in! In high traffic situations (stop & go) which resemble city driving, I've gotten 51mpg so far; so traffic is a GOOD thing. :)

EPA's posted numbers are not realworld numbers, but EPA is inaccurate for EVERY car out there. Consider that.

AND, don't forget emissions - even if Echo gets comparable mpg, it's not a AT-PZEV vehicle where the air coming out is basically cleaner than the dirty city air going in. This is vastly more important than mpg if you care about your health longterm.

and everyone's mileage DOES vary.

I own a 2004 Prius, and I must say that I DON'T get the mileage advertised, although I have seen per-trip variations outside what I so-far consider my normal range. My own figures are closer to 47MPG (combined) for the life of the car, now at 4000 miles. However, my style of driving tends to be shorter trips taken in a hilly locale--both of which negatively influence mileage. Slightly longer trips (a daily commute of 60+ miles) and flatter terrain (coming north to town on the coastal plain) allows a friend here (also with an '04 Prius) to average 53 or so. All other factors seem similar--we have similar driving styles, same tires at same pressure, etc.--but there's a big difference in the mileage figures for the same car. I don't think the EPA takes this into account; they're looking at a bad extrapolation of data based on emissions and a short test--almost a perfect, no-wind, flat-land drive.

I believe the Prius is a good, capable machine. I can see how, in the right circumstances, the car would do as well as, or better than, the EPA figures. Lots of folks do it.

Check out Greenhybrid.com and Prius Chat and see what others have to say.

I'm kinda bummed that a Prius video game exists and I don't have a PS2 to play it. Oh well. Good luck getting a Prius--waiting lists are at a year in some places, and dealers have figured out that they can charge premium prices...going up as far as US$12,000 higher than MSRP in some cases. I've had my new Prius for about two months, and I absolutely love it. It's the perfect geek car and it's a video game itself--you'll drive it with an eye on the consumption screen, trying to squeeze every bit of mileage out you can--a LOT more fun than it sounds. Check out Priuschat.com if you want real information about the car.

Check out this thread on a Prius users group to get some first hand, real world drivers experiences with the best car being manufactured right now!

Safety Cap is exactly right, you need to invest enough time and mental capacity to learn how to drive a hybrid (this is after all a very different system - it's not your father's Oldsmobile) but with just a little effort it is possible to beat the EPA figures.

I've "hacked" my 2004 Prius so to speak to include the EV Button which comes stock on the Japaneese and some European versions of the car. The American version not only doesn't have the button, but doesn't even have the wiring harness present to do this. Someone was able to figure out which pin on the engine computer triggers this function, and we took it from there. While some of us used the factory button imported from Japan, others have wired it using Radio Shack parts, or into the headlight flasher or the cruise control button as well for a more stealthy appearance.

This purpose of this buttion button is to allow the driver to force the car into electric-only mode for short distances at speeds under 55km/hr (34mph). This is great for sneaking home at night in close quarters, saving gas till you back out of the driveway, or for sneaking up on the old ladies in mall parking lots before laying on the horn.

If you could plug the car in, you'd even have a short range EV car. Now if only they had a button to improve gas mileage while making it do 0-60 in 4 seconds.

I've "hacked" my 2004 Prius so to speak to include the EV Button which comes stock on the Japaneese and some European versions of the car. The American version not only doesn't have the button, but doesn't even have the wiring harness present to do this. Someone was able to figure out which pin on the engine computer triggers this function, and we took it from there. While some of us used the factory button imported from Japan, others have wired it using Radio Shack parts, or into the headlight flasher or the cruise control button as well for a more stealthy appearance.

This purpose of this buttion button is to allow the driver to force the car into electric-only mode for short distances at speeds under 55km/hr (34mph). This is great for sneaking home at night in close quarters, saving gas till you back out of the driveway, or for sneaking up on the old ladies in mall parking lots before laying on the horn.

If you could plug the car in, you'd even have a short range EV car. Now if only they had a button to improve gas mileage while making it do 0-60 in 4 seconds.

Read the article.

The article states that it is unlikely Toyota will offer it in the US. This has been hashed time and again - here and ther places. Many of us on various Prius chat boards (Yahoo Groups, Priuschat.com) speculate that it's due to the litigus nature of us Americans that Toyota won't offer it. They're afraid we'll sue them the moment we use it incorrectly and hit something or someone.

I can imagine it now. If they did offer it, we'd have to click 3 screens of disclaimers, then sign the touch screen with a special pen releasing Toyota from all liability should your use of the system result in a parking fender bender or the running over of Granny Jones's teacup poodle. Even then, I can see hungry (or budding) lawyers bringing up hundreds of lawsuits over it.

Sorry guys, until we get a clue, we'll never see it here in the states. And even then, I'm not sure I'd want it in either of my Prius (I have two - a 2002, and a 2004).