In my '05 FEH, E10 is my MPG killer but for my '09 FEH it's gusty winds. Of course gusty winds hurt my '05 FEH mileage also, but E10 is the big killer in it. If I could get straight gas to compare it to E10 in my '09, I could confirm which is truely the problem. Does anyone know where I could find straight gas in Palm Beach or Martin County Florida? I've heard that marinas and airports were not required to sell ethanol, but the marinas do sell E10 that I've checked with.

I'm now breaking all my record mileages in my '05 FEH on straight gas with my '09 on E10. Has anyone with an '09 FEH/MMH compared mileage with E10 and straight gas?

GaryG

 

Straight gas should get somewhat better mileage than any mixture of ethanol & gas. Ethanol has only about 60% of the energy per gallon than gas. So if you use e10 you are getting slightly more than 95% of the energy that a gallon of gas has in it, so you will probably get about.... 95% of the mileage you got on gas.

If you can use e-85 then a gallon is worth about 60% of the energy or mileage that straight gas gives.

 

Small correction:

Ethanol ( in the commercially available form of E85 ) contains 71% as many btu as pure gasoline. 82,000 btu vs. 114,000 btu per U.S. gallon.

Interestingly, E10 has the same btu as reformulated gasoline with MTBE, which got very little discussion in the past.

A very good impartial chart can be found here:
http://en.wikipedia.org/wiki/Gasoline_gallon_equivalent

 

Back to the topic:

I have said for 4 years that hills and/or mountains give me very high MPG numbers. This is true in warm weather, with a warm engine.

Now, I moved to a home in a hilly area.
Hills on a cold (and I mean below freezing) engine are a real killer on my MPG.
I'm having trouble getting over 30 MPG with cold + many hills on my 8 miles. I have a short commute, which is nice, but my MPG numbers are really low lately.

Still, 8 miles a day at 28 MPG uses less gas than 30 miles a day at 50 MPG!

 

I try to avoid hills if possible. I scouted out a route to/from work that lets me stay on more flat roads with speeds of 45 or less and it definitely helps me keep my mileage up. This is especially helpful now that I am dealing with winterish below freezing weather. Come on Spring!

 

A small correction to your correction:

I guess it depends on your source of info. See:

http://www.cogeneration.net/FuelAndE...quivalence.htm

BTU Content
ethanol 76k
gasoline 125k

ratio 60.8%

The real issue regardless of source of info is that using ethanol with an engine not modified to take advantage of its higher octane rating (to produce more power from the energy available) is that mileage will drop significantly.

 

I think the source is the real problem here and you and I see the real truth that mileage drops significantly with E10. When you see that the oil companies and the EPA have conducted studies and you know they don't match your personal experiences, something's wrong.

Some of the top hypermilers in this county agree that E10 is a scam that significantly reduces mileage and increases GHG. I think it's California who limits ethanol to a maximum of 6% for this very reason. Obama needs to clean house at the EPA and expose the special interest and phony reports. Granted that our FEH/MMH is effected more than the EPA claims at 1-3%, but 15% is crazy with E10.

There is a long thread at CleanMPG where E10 and straight gas are being compared in real life studies with many makes and models:
http://www.cleanmpg.com/forums/showthread.php?t=11342

It also sounds strange that hills decrease mileage in cold weather. I can see the cold weather drops in overall mileage with every vehicle, but neutral coasting should help mileage in the hills over flat roads. I have no way to tell here in South Florida, but I'm going to read more from the hypermilers on CleanMPG and here on this subject.

GaryG

 

GaryG,

I've spent a career in engineering and propulsion plants, along with helping get my 3 sons thru college by getting my family suburban to go 366,000 miles (& counting... one more year). The energy content of various fuels has amazed me as the media tries to spin things.

Ethanol (corn based) specifically can be show to contribute more to the atmosphere than gas when you pull in the fuels expended to grow & ship it. Then when you consider the reduced mileage without reducing the price per gallon commensurate with the energy content...

In my Escape I see little difference in mileage except 1. High altitude such as in Wyoming, where mileage goes up as expected & 2. Cold weather (no surprise).

The cold weather thing should not be a surprise. I've put block heaters in my cars since the 70s. It helps in big cars like my Suburban, too.

Those with cold weather problems should think about their exhaust systems. If the engine doesn't heat up the exhaust system hasn't either. They will see the system low points rot out from the acids in the exhaust stream.

 

I am in Nebraska and have only had my 09 FEH (All wheel or 4x4) since October. I get about 15% better mileage with premium over E10.

The wind is what kills me along with having to run the heater constantly. I get about 5-6 less miles per gallon on the 20 or below days with a 10 MPH plus wind.

 

With regard to headwind you are captive to the electric machinery inherent in a hybrid. In a conventional car when you face a headwind you push on the gas pedal & the engine stays at the same rpm with more fuel going to the cylinders.

Notice that when you want to go up power in the hybrid the engine rpm goes up. This happens because to make the electric machines go up power you have to either increase the fields inside the machine (this has a limit with ferromagnetic saturation of the filed poles) or increase the rpm of the machines.

So when the rpm goes up the rpm goes up & the internal friction goes up costing you more gas. Premium versus regular makes no difference in engine power, the only difference is the additive package the gas company puts in.

For cold weather ops does the mileage go down on long trips? For short, around town stop & restart operation the mileage will go down because of the repeated heat up & cooldown.