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67hat34c
06-28-2006, 09:59 AM
I found an interesting site that discusses E85 fuel, appears to confirm what others have said about reduction in power, however it stated this reduction is in older engines. Manufacturers are contending that they can make an engine that will run as efficient and some more efficient that on strait gasoline. Appears Higher compression, turbo charging and computer regulated fuel delivery can do this. They also discuss pricing etc.
Anyhow here is the site address http://en.wikipedia.org/wiki/E-85

Genesis
06-28-2006, 10:35 AM
Impossible.

E85 has far fewer BTUs than gasoline. There's no way around the laws of thermodynamics.

MikeP
06-29-2006, 09:06 PM
Don't you just hate those pesky dang laws of physics?

Boss Lady
06-29-2006, 09:47 PM
You are correct about the BTU potential, but gas engine efficiency is so low that it only realizes a few percent of the available energy during the combustion process. About 90% of the energy goes out the tail pipe unburned or gets burned in a catalytic converter. If someone has the time to calculate the differences be my guest, but if a fuel will allow for higher compression ratios you can realize significant power gains (about 60 hp is typical for a small V-8 just by changing the compression ratio) and even though the BTU potential of the fuel may be lower you realize more efficient utilization of available BTUs. That is how you can gain more power out of a lower order of energy fuel. The physics don't change just the applied science. The problem has always been how to get more complete combustion. We don't even begin to use the available energy in a gallon of gas with current engine technology :D

SKYCHENEY
06-29-2006, 10:01 PM
We would probably be more efficient if we went back to steam boilers. Just burn the gas to heat the water and then drive the car with steam. How's that for an old idea made new again :D And, hey, with that we can use our coal and not have to rely on the Middle East.

Maynard Rupp
06-29-2006, 10:13 PM
We used to warm our fuel dragster engines on methanol. Same stuff as ethanol for all practical purposes.Gasoline burns at a fuel to air ratio around 13 to 1. Methanol is 6 to 1. Just about twice as many gallons to create the same horsepower. Yes, you can increase the compression ratio to about 16 to 1 and get some of that efficiency back. I can guarantee that not one single person could stand to be aboard a boat going downwind with ethanol. Your eyes burn like fire and you instincts will not let your lungs breath that air. When we raced we used almost straight nitromethane which burned at a ratio of 1.6 to 1. Now there is some serious fuel burn; about 1 gallon per second. It did not have as bad of fumes as methanol though. I think this whole craze is stupid. They can't grow anywhere near enough corn to supply the need. They also price it like it was gold. They don't have anywhere near the processing facilities that would be needed. Old carburated engines almost won't run on that stuff. Yes, you could re-jet some carburaters. The fuel consumption will scare you.

Genesis
06-29-2006, 10:39 PM
You are correct about the BTU potential, but gas engine efficiency is so low that it only realizes a few percent of the available energy during the combustion process.
Not even close to accurate.

Current gasoline engines can extract about 32-38% of the energy in a gallon of gas and turn it into rotational power. That's not a "few percent".

Diesels are ~35% more efficient, but some of that is the greater fuel density. The rest is due to both higher compression and the elimination of throttling losses, which hurt gasoline engines severely at part-throttle. With a spark-ignition engine you cannot get away from the throttling losses; only compression-ignition in an internal-combustion engine can eliminate that.

BTW, the maximum thermodynamic efficiency that can be achieved giving the working temperature of steel (that is, where the engine fails due to melting!) and the combustion temperature of the fuels involved is approximately 59%. Note that large marine diesels (e.g. 90,000 HP ship engines) have achieved over 50% (in the 51-52% range), indicating that while we can do somewhat better (without exotics), we're about as far as we're going to go in that regard.

E85 cannot deliver on the claims. Its simply impossible. While increased compression ratios can help efficiency they still have throttling losses to contend with and a lower original BTU content.

Those pesky laws of thermodynamics aren't suggestions folks..... while lots of people claim to have 100mpg carbuerators, the fact of the matter is that they do not exist - and never have.

Boss Lady
06-29-2006, 10:48 PM
Brazil took 30 years to develop alternative fuel supplies and they are a third world country. We are the ones who put a man on the moon. We haven't even tried to do anything here, because imported oil has always been cheap. It won't be cheap much longer. China and India are buying oil to run friggin mopeds and they are driving up prices, wait until they start filling up cars with gas and see what happens to prices. China also has 1 Trillion of our dollars to buy what ever they want, since everything is made there now. Biofuels will look cheap pretty soon. We better think about this or we will be walking a lot. I think we can at least go to 20% hybrid fuels and offset the costs. Diesel engines run great on biodiesel (veggie oil derived), in fact the first diesel engine was designed to try and burn coal dust, then switched to corn oil. This was like 30 years before they discovered petroliem. The bad news is it doesn't matter what any of us think, prices will continue to go up as China and India continue to develop and start consuming more oil. So we better figure something out.

rangerscott275
06-29-2006, 10:56 PM
for anyone that is in finance (or has access to Bloomberg) there is a 20 min BBG television news program about Ethanol that came out tonight...very good info on it.

Boss Lady
06-29-2006, 11:03 PM
Hey, I like my petrol as much as anybody, but if it goes to $6.00 a gallon even I will be looking for alternatives. The thought of having to become a blowboater does not thrill me. All you smart thermodynamics guys think of something! :D

GaryNW
06-30-2006, 05:43 AM
I saw a report recently that the province of Alberta alone has enough oil to supply the entire world for 100 years! The problem is that it is not in the easy-to-extract liquid form. As the value (price) per gallon increases, the economics will tilt toward shale oil processing or perhaps even coal? Perhaps nuclear plants could provide the necessary energy to make shale processing viable. Oh, and Montana is another place with lots of non-liquid oil. I believe the current governor is pushing for independence- for that state at least.
Gary

MikeP
06-30-2006, 06:15 AM
That pushing for state-independence thing didn't work too well the last time...

;)

Boss Lady
06-30-2006, 08:54 AM
I think their motivation is to divorce themselves from the rest of society, too many stupid people, and lord help us all, they are breeding. :eek:

smoothmove
06-30-2006, 09:51 AM
[QUOTE=Maynard Rupp] I can guarantee that not one single person could stand to be aboard a boat going downwind with ethanol. Your eyes burn like fire and you instincts will not let your lungs breath that air.

Maynard, your comments brought back some old memories from when my dad and I used to run around the country racing Enduro go-karts. Drafting was a technique we all used (I think mostly to act like the BIG car guys) You could put up with the sand and rocks thrown off by the fellow in front smacking you in face, but every once in a while you'd get blasted by a good dose of methanol, castor oil, and nitromethane. Then it seemed prudent to back off a little while you attempted to regain your eyesight. I don't know if ethanol is as bad, but we'll all sure find out soon, as the politician's inherent bias seems to see only good things in the ethanol economy. (IMOH they're goofy) I have a couple of E85 stations within a mile of my house.

By the way, one of the karts we owned was a "Rupp" go-kart. Any relation?