Ethanol Free Gasoline

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Forgive me if this has already been hashed out before - several of our newest QuikTrip stations in my area are starting to carry ethanol free 87 octane petrol. It's a bit pricey, about $0.50 a gallon higher than standard 87 octane.

Question is without the ethanol, what is added to the fuel to raise/lower the octane to that 87 number? Is there going to be any long term benefit by using it in a car versus the alcoholgas? (the bike loves the stuff)

Some other stations carry an array of ethanol free ranging from 89 to 93 octane, but this QuikTrip is @ 1 mile from me. Thanks.
 
Originally Posted By: HouseTiger

Question is without the ethanol, what is added to the fuel to raise/lower the octane to that 87 number?


Usually Toluene or Xylene.

I think it smells a LOT like 100LL AvGas.
 
Real answer depends on refinery configuration. There's no blanket answer.

But in general, the answer would be less lower octane blend stocks like natural gasoline or light straight run naphtha are used in an ethanol free blend than one that will be later blended with ethanol.

Seasonal volatility specs allow more normal butane in pump blends in lower ambient temperature months than higher ambient temperature months, and n-butane has a high octane value. So again everything varies by season as well as refinery configuration, as well as how a refinery operates with a partial shutdown (only some units shut down).

High octane components that a lot of energy has been spent to separate & purify like toluene and xylene are normally sold as petrochemicals - when used in gasoline blends their use tends to be in the higher octane grades like premium, not 87.

100LL typically contains quite a bit of toluene and a special alkylate component, as well as tetraethyl lead. Volatility is a fixed spec, not variable IIRC.
 
Originally Posted By: dareo
Rumor has it they take 91 or 93 octane and remove the ethanol.


Dumb rumor. Ethanol is the last thing added to gas as the are filling the truck for delivery. It cannot be sent through a pipeline with ethanol.

In NY the stations that sell E0 sell it has premium, 92/93 octane.
 
All I know is E0 is good for the car and it is actually have better mpg which means more efficient.

I have not done the calculation for economy on the mpg improvement vs extra price, though.
 
Originally Posted By: JMJNet
All I know is E0 is good for the car and it is actually have better mpg which means more efficient.

I have not done the calculation for economy on the mpg improvement vs extra price, though.


Ethanol on a 10% blend means close to 3% loss in MPG.

Trade-off: is the price of the 0% Ethanol gas less than 3% difference vs the 10% gas.
 
Ethanol has lower BTUs than petrol so provides less power and mpg per unit consumed.

Ethanol has higher octane than petrol, so if you have high cylinder pressure and appropriate mapping it can provide more power while delivering far lower mpg due to its stoichiometry.

Ethanol can help 'emulsify' water into petrol allowing a tank of 'bad' fuel to run better than if no ethanol were present.

Ethanol has a SIGNIFICANTLY higher latent heat capacity so cools much more than petrol as it 'vaporises' into the airstream.
 
Originally Posted By: Danno
Ethanol on a 10% blend means close to 3% loss in MPG.

Trade-off: is the price of the 0% Ethanol gas less than 3% difference vs the 10% gas.



Therein lies the rub. Right now our 87 standard petrol is $2.14 versus $2.64 for the ethanol-free stuff. Difference in MPG over the last two fills is a 2.1 (average) mpg gain, so I'm not sure the financial difference is outweighed by the benefit to the engine. Thanks for the responses.
 
Yeah, i look at the cost per mile of a fuel, not so much just the mpg. While higher mpg feels good, if the fuel to get there is costing more per mile to use, what is the benefit?

Really can't understand why this ethanol thing gets so many in a tizzy. We have had ethanol laced fuels in my area since the 70's. Cars and pickups were not falling apart even back then. My 1974 Pontiac Catalina used E10 almost from the time the fuel was around till the car finally died of body cancer in the 90's. The engine still was running great with over 250,000 miles on it. No other vehicle I have had that used E10 in has ever had any problem. I have rarely seen so many people so paranoid about something.
 
For the first time ever in my area, I found some ethanol free gasoline at a Valero about 20 miles from home.
RUG was $2.13.9/gal and the ethanol free 91 was $3.99.9/gal.
Needless to say, I bought the RUG.
 
Originally Posted By: Danno
Originally Posted By: JMJNet
All I know is E0 is good for the car and it is actually have better mpg which means more efficient.

I have not done the calculation for economy on the mpg improvement vs extra price, though.


Ethanol on a 10% blend means close to 3% loss in MPG.

Trade-off: is the price of the 0% Ethanol gas less than 3% difference vs the 10% gas.



That's the economic equation but the E091 has also a viceral effect on the machine.
 
Originally Posted By: TiredTrucker
Yeah, i look at the cost per mile of a fuel, not so much just the mpg. While higher mpg feels good, if the fuel to get there is costing more per mile to use, what is the benefit?

Remember, though, that many jurisdictions simply don't give the option, or give a very skewed option. Here, for instance, the only way to get E0 is to buy premium. Of course, that throws pricing comparisons right out the window. Interestingly, the ethanol enhanced premium (we have only one example) here costs more, since it's regular premium, plus ethanol. The same station, Husky/Mohawk, has an ethanol free premium, and a higher octane ethanol premium.

So, has anyone ever seen an E0 87 side by side, at the same station, with an E10 87, without and octane rating games or subsidies or anything else to cloud the issue?
 
That's skewed, too.
wink.gif
The lake crowd gets ripped off!
wink.gif
 
Originally Posted By: Garak
That's skewed, too.
wink.gif
The lake crowd gets ripped off!
wink.gif




they scorch a lot of fuel just on the water.
 
I live in eastern Iowa and our 87 now costs ~$.50 more than E10 89 whereas it used to only cost $.10 more per gallon. The local media interviewed a local station and they said that what the refineries were sending to our terminals was 84 (or maybe even 83 octane, can't remember) and the terminals were then blending it with the 91 octane to bring it up to the 87 level.
The odd thing is that in western Iowa where the majority of the state's ethanol plants are located, is that non-ethanol 87 is still only $.10 per gallon higher than E10. E15 is easier to find over here (Cedar Rapids - Iowa City area) than it is out west and E85 seems to be easier to find out west than it is here.
I have a Fas Fuel (formerly Road Ranger) card that discounts their 87 non-ethanol an average of .$10 per gallon so I make use of that and keep my hard earned mpg.
Any way, just my $.02.
 
Originally Posted By: Danno


Ethanol on a 10% blend means close to 3% loss in MPG.

Trade-off: is the price of the 0% Ethanol gas less than 3% difference vs the 10% gas.

Not for me. In my '04 Elantra I had a 10% decrease in mileage with e-10 (went from a consistent 36-38 mpg with e-0 to 33-34 mpg with e-10).
I can't compare any other of my vehicles since e-10 is mandated here.
I know when I went to OK City, I can get e-0 for around $0.05-0.07 more a gallon (at least the last time I was up there a few years ago) and was well worth the price for the drive home.
 
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