CAFE only counts the Gasoline not the ethanol.

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Looking up the Ricardo stuff that's been talked about to find the actual, not spun skinny on it, came across ...

http://www.caranddriver.com/news/ricardo-announces-a-better-way-to-use-ethanol-car-news

Quote:
E85 currently costs about 10 percent less than regular gasoline in most areas, but because of its lower energy content delivers a 30-percent reduction in fuel economy. It’s no wonder the vast majority of the millions of E85-capable, flex-fuel vehicles on the road never burn the stuff. The reason these flex-fuel vehicles exist is a regulatory loophole that allows the automakers to boost their fleet fuel-economy average (CAFE) because the government only counts the 15 percent gasoline content when calculating mileage. A flex-fuel Chevy Tahoe, for example, received an absurd 97-mpg E85 rating, which boosts that all-important CAFE number.



http://www.caranddriver.com/features/ethanol-promises-e85-and-fuel-economy-page-7

Quote:
With fewer than 600 stations selling E85 fuel in 37 states, why have GM, Ford, and DaimlerChrysler been cranking out these flex-fuel vehicles by the millions?

The answer is the mandatory Corporate Average Fuel Economy (CAFE) standards. Federal law requires that the cars an automaker offers for sale average 27.5 mpg; light trucks must achieve 22.2 mpg. Failure to do so can result in substantial fines. However, relief is available to manufacturers that build E85 vehicles to encourage their production.

The irony here is that although E85 in fact gets poorer fuel economy than gasoline, for CAFE purposes, the government counts only the 15-percent gasoline content of E85. Not counting the ethanol, which is the other 85 percent, produces a seven-fold increase in E85 mpg. The official CAFE number for an E85 vehicle results from averaging the gas and the inflated E85 fuel-economy stats.
 
But, that's not cheating, right? Having 97 mpg in a Tahoe is fine because it can use E85 and only real gasoline counts, whereas only passing emissions when actually being tested is cheating. Right....

I always did wonder about the proliferation of flex fueled vehicles. At least the States has 600 stations selling E85. I think there are one or two only in Canada. I checked one day and reported here; be darned if I can remember for sure, though.
 
If only the owner only had to pay for the gasoline component.

Have bemoaned that when E10 hit Oz, petrol was $1.00/L, and E10 was $0.96...made it worthwhile.

Now E10 is 3c cheaper out of $1.25 (was 3c in $1.60 relativelt recently), and that's when they pushed to make it mandatory...when it clearly didn't save the motorist money.

Have an E85 station in Bathurst, and it's clearly not viable to run the E85...the owners have worked it out, and Holden are dropping it.

http://www.drive.com.au/motor-news/ethan...0205-1ahgx.html

Quote:
Fuel use on the freeway for the E85-fuelled car averaged out at 9.6 litres per 100 kilometres. That's 21.5 per cent more than the most frugal of our trio, which was - predictably - the car fuelled with premium unleaded (7.9L/100km). The E10 car was sandwiched in between, using 8.2L/100km.

However, it was the E10-fuelled car that was the cheapest to run over the entire 1764-kilometre, two-day highway trip. It used $172.65 in E10, compared with $189.15 worth of 98 RON for the car running on premium unleaded.

Somewhat surprisingly, the E85-fuelled vehicle cost the most at $194.68.
 
I like having a flex fuel because it offers me the widest flexibility of using the fuel that offers me the lowest cost per mile.

It is 2015 2500HD Silverado, which is not going to be a candidate for economy vehicle of the year, but the numbers work this way...

E0 near me is running about $2.26
E10 near me is running about $2.16
E85 near me is running about $1.75

I get roughly the same mpg average on E0 and E10 for all my normal day to day stuff which includes a lot of rural gravel roads, off road, to and from town on rural, curvy, hilly two lane roads, etc. For all of this, the pickup generally averages around 14 mpg.

With E85, the mpg does drop, but not precipitously. About 2 mpg. So, for some reason, the claim that I will lose 30% fuel economy on E85 did not play out. To be fair, it did somewhat with the 5.3L in my previous 1500. But the 6.0L in this 2500 did not suffer as big a spread.

So, E0 at $2.26 and 14 mpg gives me a cost per mile of roughly 16.1 cents a mile.

E10 at 14 mpg and $2.16 a gallon gives me a cost per mile of roughly 15.4 cents a mile.

E85, at roughly 12 mpg and $1.75 a gallon, gives me a rough cost per mile of 14.6 cents a mile. So it offers a 1 cent a mile lower cost at the present pricing or E10 and about 1.5 cent a mile savings compared to E0. Not a tremendous amount, for sure, but I am a business minded person, and I crunch numbers on things like this.

As seasons change, so do prices. Most of last spring, E15 offered the best value. Right now, E85 offers the best value. By winter, who knows. It could be E10, E0, or any of the other blends available to me. I really don't care. I just get what will offer me the lowest cost per mile.

Of course, different areas of the country have different pricing. In some areas, using E85 is stupid, from a cost per mile basis. Fortunately, I have E0, E10, E15, E20, E30, and E85 available all around me, throughout the year. Sad that such a broad number of selections aren't available to everyone.
 
Turtlevette, I usually take anything mathematical C&D says about fuel economy with a grain of salt. They drive the heck out of the cars and then complain they don't get EPA mileage.
wink.gif


In this case, they were actually talking about E85 giving them 30% less fuel economy, rather than the 10% alcohol additive as in E10. I had to read it twice to make sure. But you are right to wonder. They have come up with some real mathematical gems in the past.
 
Originally Posted By: turtlevette
Yea, that's ghetto writing. How dumb do you have to be to think a 10% additive with 30% less energy content yields a 30% reduction in mileage. The guy's a punk.


What ?

gasoline, LHV 44 MJ/Kg, density 0.75, 33MJ/L
ethanol, LHV 26.9 MJ/Kg, density 0.785, 21.1MJ/L

36% less energy per litre...so firstly, you math is wrong.

In 85% concentration (you DID read didn't you before declaring hack, or is reading and comprehension failing too ?), resultant 22.9MJ/L...give 70% of the energy per litre.


So 30% mileage hit for 85% Ethanol is entirely thermodynamicaly reasonable
 
Originally Posted By: Garak

I always did wonder about the proliferation of flex fueled vehicles. At least the States has 600 stations selling E85. I think there are one or two only in Canada. I checked one day and reported here; be darned if I can remember for sure, though.


Not sure where you got that number, but a quick search netted that there are over 2500 retail outlets that sell E85 nationwide in the U.S. That was as of 2013. Only New Hampshire and Alaska do not have E85 available.

http://farmfutures.com/story-more-stations-offering-e85-0-109706

This station locator lists 2678 outlets that have E85 in the U.S.

http://www.afdc.energy.gov/fuels/ethanol_locations.html

Thing is, for various reasons, most people just don't look for them. Sure, they are more prolific in some areas of the country, but they are out there. Most folks only concentrate on mpg and not cost per mile. If they did, then there might be more folks who seek out E85. But some never will because of bias or some other idea.
 
Originally Posted By: Shannow
Originally Posted By: turtlevette
Yea, that's ghetto writing. How dumb do you have to be to think a 10% additive with 30% less energy content yields a 30% reduction in mileage. The guy's a punk.


What ?

gasoline, LHV 44 MJ/Kg, density 0.75, 33MJ/L
ethanol, LHV 26.9 MJ/Kg, density 0.785, 21.1MJ/L

36% less energy per litre...so firstly, you math is wrong.

In 85% concentration (you DID read didn't you before declaring hack, or is reading and comprehension failing too ?), resultant 22.9MJ/L...give 70% of the energy per litre.


So 30% mileage hit for 85% Ethanol is entirely thermodynamicaly reasonable




We keep having the same arguments over and over. You assume 100% conversion efficiency to energy. Ethanol is more efficient.
 
Originally Posted By: TiredTrucker
Not sure where you got that number, but a quick search netted that there are over 2500 retail outlets that sell E85 nationwide in the U.S.

That was the number in the C&D article. 600, 2500, whatever. It's a heck of a lot more than there are in Canada, even correcting for population; that was my main point. I see a lot of flex fuel vehicles up here, with no way to buy E85.
 
Well, on paper, he may be correct. I can only speak to my personal experience, and with my vehicle, there is not the great 30% mpg loss from using E85. I lost about 15% mpg. I suppose it is true with some vehicles that they would lose 30%, as engines, ECM programming, and other variables come into play. Each person has to determine for themselves with their vehicle. And engines built with E85 as their primary fuel are challenging traditional assumptions. They are getting almost diesel equivalent power, torque, and fuel economy even with the lower BTU E85 blend. There is more to a fuel than just BTU. Ethanol has unique characteristics, that when taken advantage of, really can make it a serious fuel.
 
Originally Posted By: Garak
Originally Posted By: TiredTrucker
Not sure where you got that number, but a quick search netted that there are over 2500 retail outlets that sell E85 nationwide in the U.S.

That was the number in the C&D article. 600, 2500, whatever. It's a heck of a lot more than there are in Canada, even correcting for population; that was my main point. I see a lot of flex fuel vehicles up here, with no way to buy E85.


Well, I would assume it is not as practical. The upper midwest of the U.S. is awash in corn which is the primary feed stock to make ethanol in the country. And transportation costs are minimal. Canada doesn't have the crop output near as great, so any appreciable use of ethanol would mean that it would have to be brought in. The transportation costs negate any real benefit.


Not to worry, the more E85 I use here where it is more practical to do so, the less gas and that helps keep the gas prices lower for others. And since it is only a $100 upgrade to make a E85 version of a vehicle compared to a regular vehicle, it is real practical to make a slew of them and let the customer decide what to fuel it with. Better to have the flex fuel capability and not need it than to not have it and have a situation like mine, where it saves me bucks to fuel with E85.

If that helps the OEM's to get around the CAFE stuff, more power to them! I am for tricking the government up at every turn. I did it with my 2013 semi truck. I ordered the truck without a motor. I then dropped in a pre-emission factory rebuilt motor. All legal and EPA approved. I saved a grip of dollars and a lot in maintenance and operation cost.
 
Originally Posted By: turtlevette
We keep having the same arguments over and over. You assume 100% conversion efficiency to energy. Ethanol is more efficient.


I don't assume anything, I've stating the energy content of a litre of the brew.

Are you claiming over 100% efficiency for ethanol ?

I seriously hope not, but that's the basis of your argument there.

OK...show me where ethanol efficiency exceeds gasoline, otto, brayton, rankine...show me.
 
Originally Posted By: TiredTrucker
Well, I would assume it is not as practical. The upper midwest of the U.S. is awash in corn which is the primary feed stock to make ethanol in the country. And transportation costs are minimal. Canada doesn't have the crop output near as great, so any appreciable use of ethanol would mean that it would have to be brought in. The transportation costs negate any real benefit.

You're probably right. We're able to hold our own in ethanol production with respect to the current fuel mandates, but I'm not sure how that would translate if a bunch of stations decided to be selling E85 simultaneously.
 
Originally Posted By: turtlevette
Ethanol is more efficient.


OK, here's a Ricardo statement...which was what I was looking for in the first place.

http://www.ricardo.com/en-GB/News--Media...-Brazil-summit/

Quote:
In his presentation on Friday, Ricardo’s Thomas Apostolos said that the company's Extreme Boosted Direct Injection (EBDI) engine has the potential to deliver best-in-class efficiency for ethanol combustion. He outlined a technology approach wherein an EBDI engine achieved diesel like fuel efficiency from a spark ignited engine. Torque performance characteristics were also similar to that of a diesel across a broad range of engine speeds, when running on E85.


Diesel like efficiency...

efficiency, as a power professional would know is energy output/energy input.

And diesel like would then be comparing diesel energy inputs/outputs, the the E85.

OK, so diesel is 35MJ/L, E85 22.9MJ/L, as we previously established. So at equivalent "diesel like efficiency", that's 65.4 % of the mileage of the diesel engine in MPG terms.

Running cost ?

If E85 was 65.4% of the cost of diesel, and the engine truly were getting "diesel like efficiency", it would be a wahs.

But petrol engines don't get "diesel like efficiency"...
 
Originally Posted By: TiredTrucker
I sense trolling....


He's known for it...

Considering the original post, that for CAFE purposes only the gasoline component is considered, saving the auto makers $Ms.

Given that when they spec a lower viscosity engine oil, and must make every attempt to prevent the owner from going thicker (backsliding rules), how on earth are they going to stop flex fuel owners from filling with whatever they want/can get on the day ?

It's pretty silly to give them the CAFE credit for producing a flex fueler, while acknowledging that the owner can fill up with anything on the market.
 
Originally Posted By: Shannow


It's pretty silly to give them the CAFE credit for producing a flex fueler, while acknowledging that the owner can fill up with anything on the market.



It's just another loophole more than likely put there by a lobbyist working for the auto companies...
 
I did the simple calculation several years ago and E10 yielded about a 4.8% drop in fuel mileage and E85, I seem to remember, would result in a 15.X% drop. Too lazy to find the values again. Ed
 
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