GM says Two Mode Hybrid System Trumps Competition

Evan points out that "... it took [him] several thousands of miles to become an efficient hybrid driver."

Now there is something to the practice effect. I've had my 2005 Prius for only 2 1/2 weeks, and I love playing the fuel economy game--trying to get the average for a tank to the magic 50 mark (I've filled up twice, so far: 45 mpg both times, with which I'm quite pleased). On one 200-mile round trip I achieved 50 mpg. Given that I live very close to work, and make mostly short trips, I'll probably never exceed 48 mpg for a whole tank, but I still enjoy playing the game.

The fuel economy game, however, can be played in any car that gives you constant feedback on your fuel consumption. With practice and with accurate feedback, your mileage on any car would improve. "Pulse driving" to one side, the driving habits that yield better mileage in a hybrid are the same habits that yield better mileage in any other car. BTW, look for one of those "pulse drivers" on the news one day soon: "Hybrid driver is run off the road and beaten by a gang of angry motorists. Film at 11."

 

The first question I ask when any unqualified percentage is mentioned is: For what kind of driving? Then there's other questions, like climate and distance and speed and... followed by asking what the baseline was. All have a profound influence on the data gathered.

The topic of this thread is how the two-mode system "trumps" the competition. How exactly did they determine that? And what does trump actually mean? And how does the other type of hybrid (assist) fit into the picture? And what about the other "hybrid" system from GM?

By the way, we already had the % discussion when HSD was first introduced. The data from that supported the "close to" quote. What has changed since then?

 

Rude? You've got to be kidding. I'm dealing with a man who refuses to accept evidence, who fails to produce any evidence for his own claims, and who says I'm not "objective." Who is being rude to whom?

As for comparing apples to apples, you seem to have concluded that the only other "apples" with which it is "fair" to compare the Prius are cars with more powerful engines.

And let's not forget that you also insist on comparing conservatively-driven Priuses to normally-driven Camrys and Corollas. I think CR's test data yield a far more valid comparison precisely because the drivers were _not_ driving any differently. Any car can be driven conservatively, and the result will be much-improved fuel economy. The Prius is not special in this respect.

 

While were on this topic... What have you found to be an acceptable margin-of-error?

For example, the quoted 0-60 values for Prius from the "performance" magazines varies as much as whole second. That's quite a bit. But people seems to accept it. Should they?

 

The FreedomCAR study provides data that includes lengthy testing with multiple models of the same hybrid. Here's the link... http://avt.inel.gov/hev.html

And here's the crunched numbers gathered from back in August... 6 Insights (5 CVT, 1 Manual) driven 347,000 miles resulted in 46.0 MPG. 4 Civic-Hybrids (all CVT) driven 284,000 miles resulted in an average of 38.0 MPG. 4 Classic Prius driven 380,000 miles resulted in an average of 41.1 MPG. And 2 (not broken-in yet) 2004 Prius driven only 16,000 miles resulted in an average of 44.6 MPG.

Unfortunately, I haven't found comparison data available on that website. Traditional vehicles of similar size & power driven by the same group to establish a baseline would have been quite informative... especially being in Arizona, where A/C is used a lot.

 

Well, you should be kidding. I've been rude to no one, although I have been accused of breathing SUV tail pipe fumes and being unobjective. I've even been called "rude." Have I ever called you or John anything?

Apparently, it is rude to disagree with the claim that the Prius delivers nearly 100% improvement in fuel economy. It is rude to cite evidence that throws such a claim into serious doubt. It is rude to point out that industry observers who cite 25% as the approximate improvement in fuel economy delivered by hybrid technology seem to have the available evidence on their side.

Not once have I called anyone a name. Not once have I suggested someone was high on exhaust fumes. Yet I am rude. Very well.

I compared the Prius to the Echo because they have the same size engine and they're both Toyotas. I also pointed out that the Echo was lighter, so I obviously was not trying to pull a fast one, just as I'm sure you're not trying to pull a fast one when you say the Echo's acceleration is slower than the Prius's. The Echo is actually quicker than the Prius, which is hardly surprising given its near-equal horsepower and lighter weight. If you want the numbers (if it wouldn't be rude), I'll supply them.

As for "good" and "bad" evidence, it is true that such a distinction is useful. It is also worth noting, however, that the definition of "good evidence" is often closely tied to whether the evidence supports a preconceived view--for example, that the Prius delivers nearly 100% improvement in fuel economy. Given such a preconceived idea, it would be difficult indeed to find "good evidence."

I've cited evidence gathered by independent testers who have no axe to grind (Consumers Union and Edmunds). I've cited such evidence for the Echo and the Corolla. I have rejected comparisons with the Camry, Maxima, and Passat on the grounds that such cars have much larger engines. You and John have provided anecdotes and personal testimony from Prius owners who are doing their best to squeeze every last mile out of each gallon of gas.

You say I used the "lousiest" numbers for the Prius. Keep in mind, please, that I also cited unfavorable numbers for the Corolla: CR tested the automatic "LE" trim of the Corolla; the manual 5-speed would have fared about 10% better with the same engine. Indeed, the EPA's own estimate for the Corolla 5-speed's highway mileage is 41 mpg. 41*1.25=51.25 (does that highway mileage figure look familiar to you?).

And I didn't ignore John's complaint about CR's 150 mile test. I just don't think he has offered anything better. When comparing two cars, the only valid way to compare them is to drive them similarly. It would be absurd to compare lead-foot Sammy's results with the Corolla to egg-shell Sally's results with the Prius.

Your claim that the Prius is more responsive than other cars to conservative driving techniques is just that: a claim. You say you have personal experience to back it up, but I've seen no data to support your claim. I am therefore unpersuaded. I hope you do not believe it "rude" to say so.

 

i for one have found accurate and unbiased reports on the Prius to be far and few between. and reports are nearly never based completely on fact. they are opinions. even CR states that they strive to provide comparable data on as equal a footing as is humanly possible but frequently cannot be completely identical in testing.

as for several other reviews (especially edmunds) i find many inconsistent results that differ greatly from results obtained by real people. it is apparent to me that the Prius is fighting a huge uphill battle with unfamiliarity while marching to the beat of a different drummer.

considering what the Prius has overcome thus far, that alone should tell most that there is something here. the fact are, the Prius is one of the hottest tickets in town. less than a month ago, my Dad inquired about a Prius and was told the waiting list is still 4-6 months. he bought a Camry. so the increased production of the car has not solved anything as of yet.

and is 25% good? sure it is. anything that is an improvement is good, but is it acceptable... not to me and it isnt to Toyota either. and comparing gas mileage of dissimiliar models under different conditions, terrrain and drivers is all fine and dandy and good for conversation only.

but the reality is, the Prius' vehicle efficiency rating is 37%. the vehicle efficiency rating range of 2003 cars runs from 17-20%. so you can see, the Prius is nearly 100% more efficient. this is not based on anything but science and math crunching numbers. variations of size, weight, driver, season, terrain, etc. are not considered.

so why doesnt everyone get EPA? well, other than the fall (no air, no heat) when i hit EPA 5 straight fillups, i dont hit it either. but im still over 50 mpg in a state that uses ethanol all the time. i do not commute long distances, so im not even a good candidate for the good mileage, but i get it and i found out quickly that getting it involves a learning curve that takes time and motivation to achieve. its my belief, that one can get the mileage stated, barring extreme terrain and weather by changing their driving habits.

this is something that testers will not bother to do. they want to continue their wasteful ways and use that excuse to gauge the car. if they feel that they have to sacrifice any time spent at a standstill at a stoplight, that they have a compromised mode of transportation.

that is why i listen to the people on this forum. there are just too many people here getting 50+ mpg for me to give any creedence to an article stating 40 mpg. if you want to listen to those articles, do so. but i suggest that you use your own experiences with your car. you are a new owner. why read a review when you have your own car. write a review of your own. i think you will find vastly differing results.

 

So you already had that discussion, eh? Sorry I missed the memo, guys, but now that I've seen it, I suggest you revisit that discussion. Somehow you arrived at some pretty wild conclusions.

My post in this topic was prompted by someone's indignant response to a quote from a GM representative indicating that GM's hybrid technology would deliver about a 25% improvement. From the independent evidence I've seen, I'd say they're just about on target. If they can match the Prius in this respect by 2007, then they'll only be three years behind. Not bad for Detroit.

 

I've got about 5265 miles on my Prius. Doing the math with all my miles and all my gallons, taken from all my receipts, my MPG has been 51 MPG. I figure the more miles one goes, the less relevant the "bladder" is in figuring your MPG.

My first tank I drove quite conservatively and went 550 miles. The bladder makes it impossible to be accurate but it must have been about 55 mpg. I drove a little less conservatively on my second two tanks and went about 520 miles.

On my 3rd tank I purposely drove it like a sports car... fast off the line and up to 90 mph quite consistently. I got about 43 mpg. I was impressed by it's responsiveness.

Since then, I've gone to driving just like I always have. I try to be kind of smooth with my acceleration, but I don't go crazy with it. My highway speeds are up there up to 75-80, but I don't "floor it" to get to those speeds.

I suspect that the winter is going to lower that average, probably in the 46 mpg range.

My wife owns a Corolla. My car does seem to be a similar size but I think it drives smoother and faster and I have slightly more room in the back. I've figured her mileage over 3 tanks at about 33MPG.

I've been in a Camry and my car is probably slightly smaller inside, but not by much. I haven't been in an Echo, but I feel it is unfair to compare the Prius to the Echo. To me, the Echo is a toy compared to the Prius.

Now, does my experience constitute "data" or is it just a "claim".

And I'm not sure it's fair to compare the Corolla or the Echo to the Prius. To be truly fair we should compare a GM or Ford or Chrysler 5 passenger car to the Prius. Then we WILL get 75% to 100% better numbers.

 

Okay, so we have all these bad guys reviewing the Prius. By the way, Edmunds's long term review of the Prius was far from neagative; indeed, it was glowing, and the tester (mostly one driver for those 4,800 miles) said he thought he could have gotten about 50 mpg if he'd tried really hard.

But about this "vehicle efficiency rating": what is it? I've never seen such a rating--still less expressed as a percentage. A search on Google yielded no hits with that phrase, so perhaps others call this animal by a different name?

 

its on Toyota's website. i believe that John has some data on his website also.

the rating is not something you will see in a car magazine as it doesnt deal with gas mileage. its a rating on how well the car ultilizes the energy it gets from the gasoline it uses.

 

Since you ask, I'd say your experience consitutes an anecdote. Your Prius and your wife's Corolla have two different drivers with two different sets of driving needs and habits. As for performance, independent testers have found the Corolla to be the faster car. The Corolla's 0-60 time is 9.8 sec; the Prius's 0-60 time is 10.5 sec. But then the Corolla generates more horsepower with a 20% larger engine, so it's not surprising that it should be faster.

As for the best comparison, I just think it's really silly to use seating capacity as your main criterion (although the Corolla does seat 5). On that basis we might compare a Ferrari with a small Yamaha motorcycle: they both seat two. Or we might compare the Hummer 2 with the Rav4: both seat 5.

 

Then perhaps John can help with this one. He must have used different language, because Google has his site indexed.

 

i wonder if you are willing to believe anything other than what you already know. you state generalities such as the hybrid system will provide 25% more efficiency. well maybe GM's hybrid system will, but that isnt the case for the Prius and the corolla doesnt get 41 mpg around here.

i had one, granted it wasnt a new one, but its EPA rating was pretty high... much higher than i ever got driving the car. and couple that with the fact that ethanol gas is required year round here makes it even tougher.

but about 35-36 mpg is closer to the truth. i wish i had the car so that i could have tried it using the same driving techniques i use now. but as Evan said, many of the things i do in the Prius, i did with my Ford and cant say that i saw any difference at all. and when i was spending $100 a week for gas, i was trying everything.

http://priuschat.com/forums/album_pic.php?pic_id=1051

 

Have you read my posts? I have not "stated generalities"; instead, I have posted calculations based on data gathered by independent sources. These sources test cars under similar conditions.

I consider your misrepresentation of my previous posts, well, inconsiderate.

 

the whole thing is still vapour ware.

 

according to CR although they attempt in every way to duplicate test conditions, they simply cannot. therefore they say that the mileage figures are for comparison purposes only, and will vary from driver to driver, season to season, daily traffic conditions, etc.

so the tests they have can only be basically opinions based on the terrain, driving style, traffic conditions and in the case of the Prius, even the time of day will affect gas mileage.

on the vehicle efficiency rating, those numbers will not equate equally to economy.

also, there have been cases when CR did side by side driving tests of identical cars and still came up with significant differences in gas mileage performance. and bladders are not a factor in the method they use to measure the mpgs. but their data is for the most part, statically insignificant.

your very own car has already provided you with more data. as i suggested earlier in this thread,

i suggest you write your own review and draw your own conclusions