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JT64

The $ = gas used = miles/mpg stories are coming!

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http://www.cnn.com/2007/AUTOS/06/06/why_hy...suvs/index.html

gas used = miles/mpg

inverse proportional relationship is getting attention!

Over 15,000 miles,

16.5 mpg = 909 gallons used.

20 mpg = 750 gallons used.

3.5 mpg difference = 159 gallons saved.

To save as much on a car,

26 mpg = 577 gallons used.

36 mpg = 418 gallons used

10 mpg difference = 159 gallons saved.

The relationship is inversely proportional, a hyperbola.

gallons used = miles/miles per gallon

y = k/x

Posted Image

mpg improvements on low mpg vehicles are much more significant than mpg improvements on high mpg vehicles.

aka "diminishing returns" if you're mathphobic.

Edited by JT64
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Drawing a big circle around one number - say 35 miles per gallon - and saying "a vehicle isn't fuel efficient unless it gets 35 miles per gallon" is silly, simplistic and pointless. It's counterproductive because it keeps car companies focused on saving fuel where the savings are needed least. The best way to an get eye-popping miles-per-gallon number is by piling advanced hybrid technology into an already-efficient small car. It gets headlines, but it limits the real impact of the technology.

Car companies such as General Motors, which sells 70 percent of all large SUVs, and Chrysler are doing the right thing by putting their best fuel economy technology where it's actually going to do the most good: in vehicles that really need the help.

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This is why GM's first hybrid was a bus, and the first commercial one a Silverado!! Makes so much more sense.

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I'd take a '04-07 Silverado/Sierra hybrid over any other hybrid currently on the market. Seriously.

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This helps people understand why hybrids of all vehicles, including large trucks are great.

As this story says, 13,000 hybrid buses = 500,000 Priuses.

http://autos.msn.com/advice/article.aspx?contentid=4022529

But it doesn't take away the fact that hybrid small cars are great too.

The Camry: 24 mpg--> 34 mpg --> 184 gallons saved over 15,000 miles.

10 mpg difference.

The Prius: 30 mpg --> 48 mpg --> 184 gallons saved over 15,000 miles.

18 mpg difference.

The Prius's savings is equivalent to, if the non-hybrid Prius were a 30 mpg compact car.

(Something between the size of a Honda Fit (29 mpg) and a Toyota Yaris (32 mpg)).

Edited by JT64
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This is why GM's first hybrid was a bus, and the first commercial one a Silverado!! Makes so much more sense.

Actually, no. Let's put this GM hybrid bus PR spin to bed once and for all.

According to the article linked above, 13,000 buses = 500,000 priuses. Whereas Toyota will hit 500,000 priuses in short order, according to this site (http://www.hybridcenter.org/hybrid-transit-buses.html) as of July 2005 there was expected to be less than 400 GM hybrid buses in use in 2006. By GM's numbers, 400 hybrid buses = 15,384 priuses. To put that in context, Toyota sold 24,000 priuses last month.

But it is worse than that. GM's claimed 60% improvement of of their hybrid bus turned out to be wildly inaccurate. As I recall, the gains seen in the King's County trial evaporated once GM was forced to put in an engine that met the upcoming emmissions restrictions. I don't recall what the end improvement was, but the 10% improvement figure indicated in the article above is likely more accurate. In that case 13,000 hybrid buses = ~80,000 priuses. And the actual numbe of buses GM sold as of 2006, ~400, = ~2,500 priuses. In other words, just under 3 days worth of prius sales.

Finally, of those 400 buses, just over 200 were for the King County trial which showed that the hybrids were only marginally more efficient than a conventional new bus. Therefore, unless they can improve the product, it may be all downhill for GM's hybrid bus sales.

Edit:

After the engine upgrade the fuel economy of GM's hybrid buses got much worse. In some cases it was worse than the old buses being replaced as well as new conventional diesel buses.

From http://seattlepi.nwsource.com/transportati...tml?source=mypi:

""This is an unanticipated development," Pingeon wrote. "We had expected the mileage figures to be much better -- these figures are below our current Breda and conventional diesel New Flyer.""

and

"That's not what was expected of the bus. In an October 2002 e-mail, Boon said, "The vendor indicates that hybrid buses can achieve up to 60 percent in fuel savings, but I am only projecting 20 percent to 30 percent given our hills and traffic congestion."

Wow. I knew it was bad, but I didn't realize it was that bad.

Edited by GXT
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I'd take a '04-07 Silverado/Sierra hybrid over any other hybrid currently on the market. Seriously.

We still have one brand new 2006 Silverado hybrid extended cab, if you'd like :)

Canadian dollars, too!

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Actually, no. Let's put this GM hybrid bus PR spin to bed once and for all.

According to the article linked above, 13,000 buses = 500,000 priuses. Whereas Toyota will hit 500,000 priuses in short order, according to this site (http://www.hybridcenter.org/hybrid-transit-buses.html) as of July 2005 there was expected to be less than 400 GM hybrid buses in use in 2006. By GM's numbers, 400 hybrid buses = 15,384 priuses. To put that in context, Toyota sold 24,000 priuses last month.

But it is worse than that. GM's claimed 60% improvement of of their hybrid bus turned out to be wildly inaccurate. As I recall, the gains seen in the King's County trial evaporated once GM was forced to put in an engine that met the upcoming emmissions restrictions. I don't recall what the end improvement was, but the 10% improvement figure indicated in the article above is likely more accurate. In that case 13,000 hybrid buses = ~80,000 priuses. And the actual numbe of buses GM sold as of 2006, ~400, = ~2,500 priuses. In other words, just under 3 days worth of prius sales.

Finally, of those 400 buses, just over 200 were for the King County trial which showed that the hybrids were only marginally more efficient than a conventional new bus. Therefore, unless they can improve the product, it may be all downhill for GM's hybrid bus sales.

Edit:

After the engine upgrade the fuel economy of GM's hybrid buses got much worse. In some cases it was worse than the old buses being replaced as well as new conventional diesel buses.

From http://seattlepi.nwsource.com/transportati...tml?source=mypi:

""This is an unanticipated development," Pingeon wrote. "We had expected the mileage figures to be much better -- these figures are below our current Breda and conventional diesel New Flyer.""

and

"That's not what was expected of the bus. In an October 2002 e-mail, Boon said, "The vendor indicates that hybrid buses can achieve up to 60 percent in fuel savings, but I am only projecting 20 percent to 30 percent given our hills and traffic congestion."

Wow. I knew it was bad, but I didn't realize it was that bad.

I'm not saying that GM has saved more fuel than Toyota. The Prius has been such a sales success that this is clearly not the case. However, I still think it makes more sense to build a hybrid bus than a hybrid compact. Unfortunately, most people don't think the way I do, or the article above does, and so the Prius sells and the buses don't.

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I'm not saying that GM has saved more fuel than Toyota. The Prius has been such a sales success that this is clearly not the case. However, I still think it makes more sense to build a hybrid bus than a hybrid compact. Unfortunately, most people don't think the way I do, or the article above does, and so the Prius sells and the buses don't.

Well they might have sold better if they had actually delivered. I get the impression that some competing hybrid buses do offer some decent gains so pehaps hybird buses will become widespread.

I'm not arguing with the basic math. But just because vehicles with poor fuel economy require a smaller percentage gain in fuel economy to deliver a greater net fuel savings than a more efficient vehicle does not mean that vehicles with poor fuel economy are the right application for a hybrid. It seems that with the state of batteries today, the opposite is true.

Take the VUE. The Greenline is rated 27 MPG city, whereas the non-hybrid is rated 22. Assuming it actually hits the rated fuel economy, that's a savings of 126 Gallons over 15,000 miles. For the Camry Hybrid I was able to find real-world numbers. CR got 24MPG for the non-hybrid and 34 MGP for the hybrid. That's a savings of 183 Gallons over 15,000 miles. So the Camry Hybrid is the more beneficial application of a hybrid, even though it is smaller than the VUE and the non-hybrid Camry gets better fuel economy than the non-hybrid VUE.

I just realized that perhaps it isn't fair to use a GM hybrid instead of a Toyota hybrid for the comparison. On the other hand, maybe it just proves the point further.

As a matter of interest, CR got 28MPG City for the Hybrid Camry, 16MPG City for the non-Hybrid Camry, and 17 City for the Hybrid Vue.

Edit: I believe one of the articles I read stated that GM's hybrid bus costs 200,000 more than their conventional bus. I believe there is a 5K premium for a hybrid Camry. That means there could be 40 more Camry hybrids on the road for the each hybrid bus. But a GM hybrid bus only saves as much fuel as ~6 small hybrids. So even in terms of cost, the small cars could be the more appropriate application for hybrids.

Edited by GXT
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I'd take a '04-07 Silverado/Sierra hybrid over any other hybrid currently on the market. Seriously.

mr construction guy wants to plug in his guy tools on the job site.

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I just realized that perhaps it isn't fair to use a GM hybrid instead of a Toyota hybrid for the comparison. On the other hand, maybe it just proves the point further.

Well, you're comparing a mild hybrid to a full hybrid. You're correct, that is not a fair comparison. I don't see how it proved a point further - that comment just seems to be showing of a bias. You can compare the two and talk about value or whatnot if you like, but in talking about value of technology in smaller vs larger vehicles, you'd better talk apples to apples. Wait a year for the 2-mode to be available in the Vue, then compare two full hybrids.

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Well, you're comparing a mild hybrid to a full hybrid. You're correct, that is not a fair comparison. I don't see how it proved a point further - that comment just seems to be showing of a bias. You can compare the two and talk about value or whatnot if you like, but in talking about value of technology in smaller vs larger vehicles, you'd better talk apples to apples. Wait a year for the 2-mode to be available in the Vue, then compare two full hybrids.

The point is that hybrids aren't inherently better for vehicles with worse fuel economy. Adding mild/full/2-mode/etc. to the mix further proves this point.

But if you want we can compare to the mild-hybrid civic. With CR's real-world numbers, the civic non-hybrid gets 28 MPG and the hybrid 37 MPG. A net savings of 130 Gallons over 15,000 miles. Again, the civic saves more fuel than the VUE even though the non-hybrid civic is much more efficient than a non-hybrid Vue.

On the topic, Mortorweek reviewed 8 CUVs this week. In their real-world tests the Honda CR-V came within 1 MPG (27 vs 28 as I recall) of the Hybrid Vue. Motorweek tends to get high MPG (the CR-V is rated 22 city and 28 highway). Driving Television also reviewed a hybrid VUE this past week and got only 21 MPG in mixed city and highway driving.

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