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Associated Press
This marks the third year in a row the mandated levels have been reduced

All across the country today, most of the gasoline that is sold at the pumps by all major fueling stations has 10 percent ethanol in it. Some station may sell fuel that has no ethanol, but 10 percent is usually the norm. Some automakers feel that ethanol needs to be eliminated to hit future fuel economy standards.

Supporters point to the claims that the use of ethanol reduces the amount of fuel we need from imported crude oil and creates jobs for farmers who grow corn. It’s estimated that about 40 percent of the corn grown in the U.S. goes into ethanol production. Corn, however, isn't the only plant material that we can get ethanol from.

Cellulosic ethanol comes from non-food crops and the EPA had expected the use of this sort of ethanol produced from plants like switchgrass, waste products, and woody pulp to increase significantly. The problem is that the mass production of cellulosic ethanol hasn’t happened the way the EPA envisioned. An energy law passed in 2007 mandated that the U.S. was to use 500 million gallons of cellulosic ethanol in fuel by 2012. The fuel hasn’t been made in significant enough quantities to meet that goal and the EPA is now proposing a cut back on the goal. 

The EPA wants to cut the goal back to no more than 12.9 million gallons of the cellulosic ethanol in fuel next year and based on market availability of the fuel that number could be far less. The Detroit News reports that this is the third year in a row that estimates for cellulosic ethanol use have been slashed. Previously the target for 2012 and 2011 for cellulosic ethanol use were 100 million gallons each year, which was cut to 6.5 million gallons for each year.

The EPA said, "[We will] continue to evaluate the market as it works to finalize the cellulosic standard in the coming months. The agency remains optimistic that the commercial availability of cellulosic biofuel will continue to grow in the years ahead."

To reach the future goals for cellulosic ethanol production, the government is looking to help companies break ground on new refineries to produce cellulosic ethanol. President Obama said in March, "Over the next two years, we'll help entrepreneurs break ground for four next-generation biorefineries — each with a capacity of more than 20 million gallons per year."

The reason for the big push to move from corn-based ethanol to cellulosic ethanol is that some claim the high use of corn for fuel is driving up the price of some food products.

The U.S. Senate recently voted to repeal the subsidy on ethanol of $0.45 cents per gallon.



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RE: Direct Injection
By FITCamaro on 6/23/2011 12:04:07 AM , Rating: 2
quote:
Engines that can adapt the advance curve to best utilize whatever fuel comes along are not designed for any particular fuel.


A car that recommends 87 octane will not make any more power running 93. Period.

quote:
That's only 1 factor. As long as you mitigate pre-ignition you can keep increasing it, which is what you've seen over the last few years.


Pre-ignition only occurs when running too low of an octane fuel in an engine with higher compression designed for higher octane fuel. Yes these days this is largely mitigated with the use of knock sensors and adjusting spark timing in the computer. But you will have less power and lower fuel economy as a result.

In some vehicles, namely older ones, if the engine calls for 87 octane, running 93 octane will result in the burn taking too long. Resulting in unburnt fuel being ejected from the chamber when the exhaust valves open. This means you used the same amount of fuel, didn't burn it all, resulting in a smaller bang, resulting in less power, and resulting in poorer fuel efficiency.

From a guy who builds engines I was told you want to run the lowest octane that doesn't ping. Anything higher and you're wasting your money. Running higher grade fuel than the recommended octane is nothing but that, a waste of money.

Now start modding the engine, and that changes things.


RE: Direct Injection
By TimboG on 6/23/2011 1:17:17 AM , Rating: 2
quote:
Resulting in unburnt fuel being ejected from the chamber when the exhaust valves open.


All of the last 20 years worth of engines have camshafts that are designed to "scavenge" unburnt fuel back into the cylinder to be re-burnt.

The fact is that since the burn does not happen prematurely when using a higher octane fuel without ethanol gives an overall increase in torque, not horsepower.
With the gear ratios reaching above 1.4 to 1 in all new cars that increase in torque yields an overall increase in MPG. Everyone keeps screaming power/horsepower, neither of those mean squat while running the gear ratios we do now requires more torque to maintain any real advantage of an increase in MPG.

Yes, I know everyone wants to blow their horn about ethanol but the truth is that with the decrease in torque lowering overall MPG we still end up burning the same amount of petroleum to go the same distance with today’s engines and electronics.
Why a decrease in torque with ethanol while ethanol prevents spark knock?
Simple. Ethanol has a lower BTU than petroleum fuels. With a lower BTU neither torque nor horsepower can be mathematically equivelent at the peak ignition timing. The higher the pressure at the time of ignition the higher the available torque and horsepower. That is taking into account the available BTU to extract the “power”or"torque" from.

Most engines, even the non-E85 engines are seeing a 10% decrease in MPG with the addition of the 10% ethanol. So that the 10% ethanol in your tank did nothing but prevent spark knock. Since the knock sensor did not see a problem the ECM allowed the spark curve and injector pulse width to remain at the normal, preprogrammed parameters so the engine would produce the maximum power/torque available from the specific engine design.

If this does not prompt you to study basic physics in relation to burn timing vs. BTU and to only start typing, I can’t help you.

My English sucks, good thing I studied physics.
Thanks


RE: Direct Injection
By YashBudini on 6/23/2011 7:17:39 PM , Rating: 2
quote:
Pre-ignition only occurs when running too low of an octane fuel in an engine with higher compression designed for higher octane fuel.

My point was and is today's engines have techniques like squirting oil onto the underside of the piston to cool it, which allows more compression on regular gas without detonation.

(Preignition can also occur when carbon deposits build up. )

Compare typical compression ratios today versus 10 years ago, they are still climbing.

quote:
with the use of knock sensors and adjusting spark timing in the computer. But you will have less power and lower fuel economy as a result.


With this scenario a company can claim the car runs on regular fine (and it does relatively) while still offering something more with better gas, which is what I initially stated. Dive through the last decade of car reviews in Car & Driver, quite a few cars "required" regular gas, but also stated (premium is recommended) by the manufacturer.

Yeah I get zippo from going from mid grade to premium, but going from regular to mid grade my engine has less hestitation.

Also consider - If a company like Amoco filtered out all the resins and varnishes out of their premium how could they dispose of the gunk? Dropping it into their lower grade gas is one option.


"A politician stumbles over himself... Then they pick it out. They edit it. He runs the clip, and then he makes a funny face, and the whole audience has a Pavlovian response." -- Joe Scarborough on John Stewart over Jim Cramer














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