vlad_a

Sweet videos! Interesting that a permanently-engaged clutch-type device is used a dampener.

Dolphin

I tend to avoid these discussions, as I always marvel how human passion / loyalty can distort an otherwise sensible discussion. I have been on nrg evaluation panels, and often watched inventors with dual phd's trip themselves up, when it comes to their energy inventions. Rarely is this done on purpose, instead, people often get too caught up in details. One must learn to step back and continuously evaluate the big picture. But for fun, I will try one more time....

>I disagree that the net effect is zero. I noticed during the winter, people complained about getting 15MPG in the RX350, while RX450h gets about 25. On short trips in the loaner RXs, I never got over 19MPG.

My position is simple. It does not involve peoples personal experiences where many variables are not properly evaluated or controlled.
Vehicle makers are forced to follow a set of specific guidelines to determine fuel efficiency. The outcome of mpg ends up on the cars sticker we all view in the showroom. Under this form of controlled testing, which level the variables, 450h and 350 get the same hwy fuel economy. Are seem to be disregarding these tests. So, are you suggesting for hwy driving, 450h hybrids are more fuel efficient than 350? If so, how is the standardized testing failing us? (that is not sarcasm, its an honest question)

vlad_a

According to Lexus, RX350 gets 18/24/20 (AWD) 18/25/21 (FWD) 18/26/21 (F SPORT) MPG
RX450h is rated: FWD – 32/28/30 AWD – 30/28/29.
Judging by the EPA numbers instead of real life experience, 25<28 (FWD) and 24<28(AWD), 26<28 (F SPORT).
What is the point that you're trying to make? That Toyota flopped with the Hybrid technology? We can move this discussion to the EPA numbers thread that went more into details of what they actually represent.

The big picture is, I get 29MPG along with a more advanced drive train at an additional cost that I was willing to pay.

Dolphin

There is no "flop" with any of the hybrids per say....
My point was, as I mentioned from the start ....
hybrid efficiency improvements are a result of brake regeneration and lower speed traveling where engine output can be better controlled... that's it. I doubt anyone would buy a hybrid for the ~10% fuel eff. savings you showed above.

As per Jims comments regarding "payback"....very true Jim. The hardest obstacle to overcome in my field of nrg engineering, is "payback" for efficiency improvements. A comical example that demonstrates the publics desire to go GREEN and reduce fossil fuel use. I watched a township years ago scream for GREEN nrg.... after spending $400k on engineering studies, they solicited proposals for solar farm providers to sell them power. The cost was $.28 per kwh, vs. the $.07 they were paying with current fossil fuel generation. Everyone realized, GREEN nrg would increase their home electric bill 4x. A poll was taken with all the proponents who drove the initiative, and 99.9% of the proponents voted NO to Green.
I would suggest however, that hybrid technology, which is specially appealing to city drivers, would sell even better if the Feds would more aggressively subsidize such purchases. IIRC, since 2010 I think all Fed tax credits have ended for hybrids. I am working off memory, hopefully someone can correct this if there is hybrid credits, as I am curious.

Quadro

This is completely not true. GM knew from the initial design stage that their way is going to be less efficient than Prius. But they made their choice based on the average commute distance people do. They figured that they can give people the ability to travel this distance using electrical motor alone and engage the gasoline engine if people need to go further thus providing them with complete "electrical car experience" for most of the commutes they do.

Nobody was hiding anything, on the contrary, Bob Lutz described the design and the above choice (which wasn't an easy one) in his book about GM.

vlad_a

My reference is not about poor fuel economy of the Volt, but to the fact that they promised a series-hybrid, where the gasoline engine would have no mechanical connection to the wheels and would serve only as a power generator (series hybrid), but in turn, they "borrowed" from the Prius design of a planetary gear set. The engine DOES drive the wheels.

Quadro

I'm not aware of any such discussions during Volt times. Do you have any references for this? After EV1 GM was scared of anything electric regarding the cars in fact.

They did have to make a choice between a sequential hybrid (gasoline engine turns on after battery is depleted) and a parallel hybrid (gasoline and electrical engines running in parallel). It appears that "sequential hybrid" got confused with "series-hybrid" in a lot of press, including Wikipedia

vlad_a

http://blogs.cars.com/kickingtires/2...explained.html

GM's PR yelled bloody murder each time someone said Plug-in-Prius. It's hard to admit all that government money spent was on something Toyota had invented over a decade ago. It's EV-ER, not a Hybrid, people!

http://www.nytimes.com/2010/10/17/au...anted=all&_r=0

ericsan13

Thanks vlad for all the education. Let me see if I am reading this thread right:

-Front wheels: First electric motor & ICE via second electric motor
-Second electric motor: Drives the front wheels and acts like a planetary gear set
-Third electric motor (AWD only): Drives the back wheels

So even though Lexus claims it's a CVT, there is no cone transmission. It's really the second electric motor pretending to be a CVT? I wish there was a diagram.

Please correct me!

Quadro

So let's take a look here...

GM first demonstrated Volt in 2007 during Detroit Auto Show. In 2007 it was already known that Volt is a "sequential hybrid". So then in 2010 people suddenly got confused despite the fact that product was revealed 3 years before that? What they've got in 2010 was exactly what GM has shown in 2007! Now what? All I see is a bunch of press people steering crap because they were arrogant and did not follow the product. GM did not deserve this.

Disclaimer: I own a Lexus ;-)

vlad_a

GM was (still is!) very adamant that Volt is not a hybrid. What did GM not deserve? It's marketing department or the bail-out?

Quote:

Originally Posted by General Motors

Q. Is the Volt an electric car or a hybrid?
A. Volt is a full-performance electric vehicle with extended range. Volt is an innovative, never-been-done-before car that exists alone, in a brand-new category of cars.

Quadro

And how do you even know who was answering these questions? Are you sure it was even a marketing person from GM and not some press guy who overhead something during product presentation? Seriously, did people lost all common sense? "If its written in the internet it must be true". This makes no sense.

According to Bob the decision to make Volt a sequential hybrid was made before blueprints for the car even existed. That's the proposal he took to the board before Volt got approved as a product. Now THIS makes sense because you don't change horses like this.

vlad_a

Well, the link the quote above goes directly to GM's website. I sure would hope their marketing department was somehow involved in creating it.

Point is, technologically, Volt is not revolutionary. It is just a plug-in-hybrid with a large battery. It's not even that good of a hybrid. How's that for common sense?

Quadro

Ok but the Volt was innovative when blueprints were first produced. Toyota had Prius as a parallel hybrid so sequential hybrid was something new during that time. Following that logic it's actually Toyota who copied Volt with it's Prius plug-in because Prius Plug-in appeared after Volt went into production, let alone prototype models displayed during 2007.

vlad_a

Prius has always been a series-parallel hybrid. It's their Power-Split-Device what makes it special... same technology that surfaced in Volt... that Bob Lutz presented to the board (really?) to get the project approval.
I got no problem with Toyota "copying" GM in creating a plug-in hybrid. All they had to do was add a battery and a plug. Something people have been doing on their own to their Gen II Priu.