E85 Efficiency

Yes E85 saves petroleum fuel. However, it is quite a bit less effecient than pure gasoline. Also the way it is currently produced and subsidized by the Federal government it has an unfair advantage against other fuels. The corn farmer reap a huge windfall of subsidies from the Federal government to produce ethanol. If we started importing ethanol from Brazil where it is made from sugar cane and is produce at a much lower cost, then it will be worth the lower effieciency in your engine.

 

Ethanol has about 60% of the energy content of gasoline so vehicles using E85 get noticable worse gas milage. On the other hand, ethanol has a higher octane rating and if run in an engine designed for it can actually get comparable MPG. I don't think flex fuel vehicles take advantage of it though.

 

<div class='quotetop'>QUOTE(tripp @ Nov 10 2006, 02:44 PM) [snapback]347192[/snapback]</div>

The real problem with E85 is not that you have to have a hardned fuel system, but that you have to have a higher compression ration to use the fuel to its potential.

Your department is doing a great job. One other advantage might be that the oil lasts longer and in general so does the engine.

Are you having any problems with the mods that make your vehicles E85 capable?

 

E85 is just stupid.

Less mileage, similar C02 output. Its just another way for the industrial corn monoculture to get rid of the corn surplus. Guess who benefits from the industrial corn monoculture? Oil companies. The amounts of corn we produce are possible because of fertilizer manufacturing from natural gas and oil.

The oil companies love this because grwing corn is subsidized by the government. Yet another way for the government to legally give away money to oil companies. The only problem is that they affect our health both by creating a corn syrup surplus and by spewing even more C02 to the atmosphere.

Don't fall for it. There is nothing green about E85.

 

<div class='quotetop'>QUOTE(Locust43 @ Nov 8 2006, 11:17 PM) [snapback]346062[/snapback]</div>

I think I'm with Alric on this.

First, it is not clear that this saves any fossil fuels at all, because it may take more fossil fuel energy to produce the ethanol than you get out of it. I've seen two plausible studies on this, one of which says corn-based ethanol is a net energy negative (takes more fossil fuel energy to produce it than it gives off when you burn it), the other of which says its slightly positive. So, there's a fair chance that you're actually increasing US fossil fuel use by using this stuff, and if not, that at best you're only reducing it slightly. It's sure not a gallon-for-gallon tradeoff between E85 used and oil saved.

Second, why is your department is squandering the taxpayers' dollars by doing this? Per mile, E85 is expensive, because, as noted earlier, your mileage on e85 in an E85-ready GM vehicle is going to be much worse than on gasoline. For example, the US EPA says the 2007 2WD Tahoe gets 18 MPG overall with gas, and 13 MPG overall with E85 (www.fueleconomy.gov), and says that it would cost about $1000 per year more to fuel the Tahoe on E85 than on gasoline. So, your department invested millions in an E85 fueling station, so that they could substantially increase their total fuel costs? Usually, you invest in infrastructure to help cut costs, not to raise them.

Maybe someday E85 will make sense, but not today, and not in the near future. I think it's an outgrowth of our screwed-up farm policies and subsidies, direct subsidies for E85 producers, and the fact that E85 vehicles allow manufacturers to evade the CAFE mileage standards. There's no way that an unsubsidized market would have produced this, from corn, in the USA. It's unfortunate that the decision makers in your department decided to make a significant commitment to it.

 

Hi All,

Yep, E85 flex fuel vehicles as simply implemented in American SUV's are very inefficient. E85 has the chance to be efficienct - use Brazillian Ethanol (or develop an efficient domestic production method), AND a variable compression ratio engine. Now, which car has a variable compression ratio engine? And that variable compression ratio engine also requires a hybrid system to make it systematically effective. Its the Prius.

I do not believe the Prius has the sensors to detect the E85 ratio for the purpose of changing the compression ratio. And it probably does not have the compression ratio range to bring the engine into the optimum range for E85. The basic concept is what is needed for E85 to work though.

Until a true E85 flex fuel vehicle happens, and Ethanol is permited from efficienct production sources, E85 is just so much politics.

A better solution is probably bio-gasoline (bio-butanol, others?), for big simple fixed compression ratio gasoline vehicles. An effective present day bio-fuel needs to match the engines that are out there (like Bio-Diesel).

 

I think that Volvo has done some interesting work with either E85 or E100, taking advantage of the high octane to mitigate the lower energy content.

It should also be noted that ethanol in and of itself is not bad. The methods by which one produces the ethanol is the tricky bit. Already there have been numerous developments and improvements in the efficiency of ethanol production, which ultimately make the energy balance more positive. Switching over to cellulosic ethanol will help this tremendously as will advances in production efficiency. There are many new ethanol plants that don't rely on fossil fuel input for heat and electricity, which helps substantially with the emissions and fossil fuel foot print.