With the spiralling cost of fuel prices brought on by George Bush's "War On Terror", people are looking at everything to get cheaper fuel, and one of the silver bullets seems to be E85 Ethanol-blend gasoline. I say 'seems to be' because once you do some research, which is what you're doing right here by reading this, you'll learn it's not quite the magic solution everyone would have you believe.
E85 is a blend of regular unleaded petrol with between 70% and 83% ethanol depending on the geographic location and time of year. (If you must know, Google for ASTM D 5798-99). Simply blending ethanol and petrol normally results in a product with too low a vapour pressure, especially in the winter, which is why it is a process best left to people in white labcoats in refineries.
It's designed for so-called Flexible Fuel vehicles, and as such has been classified by the US Department of Energy as an alternative fuel. The facts on E85 are a little hard to come by, so I've tried to collect together and put as many as I can right here so that you, dear reader, can try to cut to the chase. So what is a flexible fuel vehicle (FFV)? Well, it's a vehicle with an engine and emissions system designed to be able to run on a blend of unleaded petrol and ethanol up to a maximum of 85% ethanol. If E85 isn't available, you can run them on just plain old petrol though. If you read all the hoopla surrounding E85, you'll see this statement crop up time and time again: "It is a renewable source of energy and reduces the crude oil imports needed to fuel America's transportation system. Ethanol is a clean, environmentally friendly fuel.". Weeeeelllllll yes. But more specifically, "sort of". It's true that it is partly based on a renewable source of energy - ethanol is basically distilled corn oil (or wheat, barley, or potatoes. Brazil, the world's largest ethanol producer, makes the fuel from sugarcane), and yes, it's a cleaner and slightly more environmentally friendly fuel. There's a few 'buts' to go with all this, and they're a big 'buts' - of Jennifer Lopez proportions. First, there isn't enough farmland to grow enough corn to produce enough ethanol to meet gasoline demands, and it wouldn't be a good use of it even if there was. Second, there's a huge hidden cost in water - it takes 10 tons of water to process 1 ton of grain for ethanol [Ref: Plan B 2.0: Rescuing a Planet Under Stress and a Civilization in Trouble by Lester R Brown. ISBN 0393328317]. And third, in bold because it's the important part of this paragraph. E85 Ethanol-blend fuel has horrible gas mileage.
What does this mean to you? Well it means you'll need a lot more of it for a start. Sure it may be cheaper than regular petrol, but there's a reason - it's a terrible way to run a vehicle. Even the governments own figures back that statement up. Check out one of their lists of flexible-fueled vehicles for yourself. On average, putting E85 in a flexible fuel vehicle will return a nauseating 25% worse gas mileage. E85 doesn't burn as efficiently as regular petrol because it contains less energy per volume - 75,760btu per gallon as oppose to 115,400btu per gallon for plain old petrol. This accounts for the 30% increase in the amount of fuel required in the fuel-air mix during combustion, and the corresponding drop in gas mileage. All this comes with an average drop of only 10% in greenhouse gas emissions. If you go by historical precedent, and assume we all move to FFV's, the income from regular petrol will drop so the oil companies will simply increase the cost of E85. At that point, you're getting terrible gas mileage but paying what you used to for just plain vanilla unleaded petrol. Remember - nothing is free. Of course this doesn't need to be the case. E85's higher octane can allow the use of higher compression, more efficient engines (if optimized for use on it). Look at the race car teams - a lot of racing engines run on pure ethanol. And when engineered to take advantage of it, high-compression, high-efficiency engines can reduce the gas-mileage deficit to about 10% less than their petrol counterparts, which is much closer. But for ethanol to be successful it must be priced below petrol so that the cents per mile cost is favorable taking into account the drop in economy.
But what about Brazil?
For a while now, Brazil (the country, not the Terry Gilliam film) has managed to be largely independent of the world's fluctuating oil prices. By law, all Brazillian petrol must be at least 25% ethanol - E25 - created from sugar-cane-fed biorefineries. By 2007, almost all cars available in Brazil ought to be able to run on 100% ethanol. (It's worth noting that Ethanol-only cars were sold in Brazil in significant numbers between 1980 and 1995). No longer dictated-to by Big Oil, the price of their E100 is relatively low and thus it offsets the lower gas-mileage quite nicely. One argument put forth in America is that using E85 will reduce the reliance on foreign imports - specifically oil. But you need to look at the whole picture. E85 comes from corn, currently a crop used to feed people. Assuming that America has enough spare capacity to farm corn for E85 for the current demand, what happens when more people start using it? You can't increase farmland, or drop production of corn for food, so the next alternative is importing it. At which point, even using E85, you become dependent on foreign imports again. Brazil doesn't have this problem because their system is in balance and so they supply themselves with enough surplus to export their product. Most likely to America.
BRON:
http://www.carbibles.com/fuel_engine_bible.html