[Article] Better Fuel Economy with Ethanol?

[gone-ot]

...here's an interesting read that illustrates that E85 can improve FE, but only with a uniquely configured engine (SIDI plus flex fuel ECU & sensors):

Development of a Naturally Aspirated Spark Ignition Direct-Injection Flex-Fuel Engine ? SAE International Journal of Engines

...summary: it's "possible" but it's NOT here yet!

[Allch Chcar]

Sorry to end my post mid-way. The answer to the question of Ethanol's energy efficiency is that the state of the art production is 1.52 units per 1 unit according to the USDA in 2005-06. The Average return is 1.3:1 not 1:1 or even .89:1 like Gasoline, and not just from Wikipedia either I've seen that number before. Ethanol is only 83% of a gallon of E85 at a Maximum, there's always 2% of the total volume in denaturant. So infact you are way offbase for a gallon of E85 since there is already a portion of low grade gasoline in with the Ethanol. And second you are estimating to the worse case scenario for a fuel conversion if you try and estimate for a Gasoline Engine's economy with Ethanol there is no way anyone would switch to Ethanol with that much mileage difference, people in the US would totally oppose it. Hence why Diesel is more attractive to YOU despite only getting better mileage due to more energy per gallon. Diesels powered vehicles need to have a much bigger and heavier engine with displacement/turbo to get the same HP so either you accept half the HP or accept the same FUEL EFFICIENCY as a gasoline car. If you accept half of the HP you're not getting better mileage because it's just more efficient which it is, but because you're running a much lower output engine. It looks fine from a MPG perspective but there's no way we can grown enough biodiesel for anything and Gasoline became more popular than Diesel for certain reasons(not discussing that part here). The production per acre of soybean based biodiesel is worse than corn ethanol and the alternatives are all tropical based just like sugar cane.

The biggest advantage like Shovel said, is that E85 can be used in the same pumps and pipelines and with some tuning, internal part replacement in formerly-Gasoline engines. Ethanol with gasoline is marginally more corrosive and gas stations can upgrade to longer lasting hoses and not lose a fortune or start a fire. Some gas stations still run Carb era pumps and fuel lines that Gasohol will eventually tear down faster than "pure" gasoline fuels and they will need upgrading to modern hoses anyway.

I think there needs be a deemphasis on Flexfuel vehicles unless they tune them to run extremely lean on E85 but instead more emphasis on DIYs building Ethanol powered engines for Daily Driven cars. There's no other economical way to do it. There has to be more demand for it. And while some car modders are picking up on E85 they use even more fuel to make better HP while Daily drivers are the most ambivalent group of them all! I see many a people turning away from using E85 because the MPG is worse or the stations are too far(15 miles in some cases). From my personal perspective that group of people is the one that will decide whether ethanol becomes a niche for hotrodders, tuners, and car modders or if it becomes the fuel of commuters as many Midwesterners have become.

I live in Kentucky and corn fields for animal feed are everywhere. The nearest E85 pump is 30 miles away and I don't commute to work, I work from home at our farm. I think it's actually easier for me to convert to ethanol having a farm in the middle of nowhere Kentucky and not commuting because I can get 100 gallons(or a month's fuel whatever it might be) at a time while in town on a grocery run and fill up our cars at home. We only go to town for food, material, tools and supplies. We don't go out on the town but once every couple months. I used to commute to school 15 miles and I thought that was pretty bad for living in a decent sized city. That is until my Dad had to commute 70 miles to work to keep his old job after moving to Kentucky . Even at that distance it was cheaper to keep his job making decent money than accept anything local because jobs out here are junk. He spends $350 a month just on fuel (and now even more for powersteering fluid) for his beater buick which still doesn't make him less money than the local jobs he's found. He commutes 60 miles now but he still makes better money than local.

Big cars are different than what we're talking about here, now if you were discussing big engines vs small engines I could see that being ontopic. I think a small displacement engine with a turbo has been proven to be practical for Daily Drivers and more efficient than a bigger engine even with lean burn.

My example is a Ford Focus compact car, 2600lbs stock with .36 CoeF 21 Sq.FT Frontal area and 24.3" Diameter tires. Factory, the 2.0l DOHC puts out about 130ft-lbs at 4400RPM depending on the year. If you could get a Suzuki G10 hooked into it with a small turbo to spit out 10lbs of boost max, then run it. On Gasoline you'd have to lower the Static Compression Ratio which is bad for Fuel and Power and still require running it extremely rich under boost and possibly even under cruise. With E85 not so, you can gear it taller, and even run it lean or stoichometric with a higher compression ratio on a stock or economy cam but with the same boost. It'd probably work since the G10 is 200lbs lighter than the Ironblock Zetec in the early Focus and the SOHC means flatter torque even if the peak is much lower. And this is without Direct Injection. The 1.3liter in the Geo Metro actually has a DOHC setup that makes 18% more HP with a higher redline but it throws torque away. It's actually one of the few production engines I've seen that doesn't have the same/similar peak HP as Peak Torque.

You'd think I was crazy but I know guys have run higher Dynamic Compression with E85, I'm a member at E85powered.com where guys customarily run higher than 20:1 Dynamic Compression under boost. Seen an article with a 12.5 StaticCR F-150 with boost but running on C16 which I've seen similar results in modded cars as E85, it was a race truck not Daily Driven so it didn't have a stock cam. I've seen a Honda guy run 12.5:1 SCR pistons on a stock Vtec cam complete with a dynamometer chart. How much extra torque you get with higher compression is also important because bottom end is where a smaller engine suffers the most in a turboed engine. If you get 30lbs of vehicle weight per 1Ft-lbs you should have enough power to at least drive around town albeit without power for high speed maneuvers.

Also, I hang out on teamswift.net forums and they get some HP out of the G10 engines. Converting a G10 to MultiPortFuelInjection and 12.5:1 Static CR and I think I could coax more than 70ft-lbs at 1500RPM out of the 3 cylinders. With a slightly shorter first gear and a similar FinalDrive x Overdrive, the MPG would be truly the same as the Gasoline version but running on E85. That's something we've not seen often enough.

I actually have an article where Ford converted a 93 Ford Taurus to E85 and besides running lean burn they installed experimental catalytic converters and got almost exactly the same MPG out of the 3.0l engine as a Gasoline powered Taurus. I'd like to know where they keep this "experimental" catalytic converter, I hear them used in E85 cars for studies but I've never seen them on the market. In my personal case I could run a no-cat E85 and still be street "legal." Technically federal law prohibits tampering with anything emissions related, but if you get legal emissions it doesn't matter what you're running according to a seperate law regarding switching the fuel the engine runs on. Technically it's been said that it is "illegal" to run anything but what your vehicle was designed for. The EPA passed a new regulation several years ago specifically for CNG conversions stating the vehicle had to pass emissions set for the Gasoline version with CNG to be smog legal. We don't have emissions programs or smog laws here in Kentucky so I think state law concerned it's "legal" to got catless and not because of lack of enforcement. But Federal Laws are sketchy because they act like they're the law of the land but legally they're meaningless in states not regulating emissions. These aren't set in stone so I feel confident that with some more research I could find the truly legal requirements of an E85 conversion. Too bad it's so much like work.

[Allch Chcar]

E85 can get better fuel economy from the same displacement by lean burn aka 14.7:1 REAL Air-Fuel Ratio. That's the same Lamda value as Gasoline at 22:1. Direct Injection or semi direct injection just gets better results from Ethanol due to the latent heat of evaporation. I'm not an expert on Ethanol's properties only that they exist. A turboed charged engine with an oxygenated/alcohol fuel like ethanol or methanol gets better results from lower octane fuels because of this trait.

It has been possible for some time, its already been done too.
20mpg Taurus.
My point is the benefit to E85 in Flexfuel vehicles is only during lean burn and HIGH compression.
The best choice for me is downsizing but adding a turbo to keep stock performance. Not necessary but nice for driving around.

And my final comment is a quote from the 20mpg Taurus Article,"Because the heat of vaporization of ethanol is 2.4 times that of gasoline and the octane number is in excess of 100, compression ratios of about 15:1 are possible with direct-injection, giving optimized efficiency for a spark-ignition engine."
Methanol is only 25% higher "heat of vaporization than ethanol so once you switch to alcohol the benefit is not as much as it is compared to switching from a petroleum based fuel. This is also the reason Ethanol has cold starting issues, it doesn't freeze till below zero but it does gel at a certain point.

I'm in favor of alcohol/oxygenated fuels as a whole not just corn based ethanol. At the best case corn-ethanol is temporary until we can mass produce ethanol. Worse case ethanol will never reach critical mass for country wide usage and production. I'm concerned about the formaldehyde(sp?) content in ethanol emissions but it's not enough to justify NOT using it. It will save more lives by a better local economy with less long distance transportation of fuel than it will by exhaust emissions. There is always the research of catalysts for cutting formaldehyde(sp?) emissions. Methanol is even more poisonous than Ethanol emissions and made from either tree alcohol or even Natural Gas so it is not an option for a renewable fuel. Gasoline is fossil fuel and altogether a poor choice of fuels. Even if it doesn't really "run out", the fuel quality will always be the lowest design limitation.

[rmay635703]

Originally Posted by Allch Chcar

Hence why Diesel is more attractive to YOU despite only getting better mileage due to more energy per gallon. Diesels powered vehicles need to have a much bigger and heavier engine with displacement/turbo to get the same HP so either you accept half the HP or accept the same FUEL EFFICIENCY as a gasoline car. If you accept half of the HP you're not getting better mileage because it's just more efficient which it is, but because you're running a much lower output engine. It looks fine from a MPG perspective but there's no way we can grown enough biodiesel for anything and Gasoline became more popular than Diesel for certain reasons(not discussing that part here). The production per acre of soybean based biodiesel is worse than corn ethanol and the alternatives are all tropical based just like sugar cane.

??? Diesel engines are more efficient EVEN VERY LARGE ONES than gas engines of any size under SPECIFIC circumstances.

One example at idle even very large diesel engines use marginal amounts of fuel, my 6.2 idles around .22gph my 3.8buick idles around .44gph. For a hypermiler idle fuel consumption is important in an autotragic vehicle.

Also most diesels DO have a higher thermodynamic efficiency than MOST gas engines, this isn't always the case, choose a 50's 2 stroke diesel and compare to a new honda insight motor for example. But under normal circumstances a diesel is literally more efficient thermodynamically.

Also, a diesel may have lower power output which you claim is the only reason for FE but that also doesn't really hold up, throw a 4 banger gasser of simlar power as my 6.2 into a suburban and compare its FE to my antique 6.2 and the 6.2 will still win. My experience with undersized gassers is that you get WORSE FE than with the larger engine, even driven responsibly.

Things are not as black and white as you make them, the truth is most diesels are built to a higher level of quality than a gasoline motor and generally have a higher thermodynamic efficiency than the cheaper gas motor. Diesels also do not suffer pumping losses which improves low end, low load efficiency, don't underestimate how large these two things are.

Cheers
Ryan

[pgfpro]

I think one aspect that needs to be look at is there needs to be a purposely built E85 vehicle. Not a SUV/Cross Over type vehicle.

To give ethanol a fair chance the manufactures need to build a small turbo engine around 1.3L with direct injection. The FE would be amazing without sacrificing HP. Plus the emissions would be extremely good.

I also don't think that we need to convert all the gasoline vehicles to ethanol. The same can be said for diesel and EV vehicles.

We need to look at all types of fuels and new engine designs and not limit any of them at this time.

[Allch Chcar]

rmay635703, you are of course correct. It's been that way since the 50's? Dang. I wasn't trying to suggest that a Diesel gets worse efficiency even in a much larger engine than GASOLINE. My point was Diesel gets better fuel economy due to Diesel's energy content AND it's thermodynamic efficiency. If you have another fuel that gets the same thermodynamic efficiency but less energy per gallon the fuel with more energy is going to look much better in comparison.

My point was that with Ethanol you get the same energy efficiency as Diesel but you can keep a smaller Gasoline engine size without sacrificing HP or even keep a Diesel engine but run a different fuel, Diesels can run any of a number of fuels with enough modification. The biggest difference considering power and efficiency is Diesel has almost twice the energy content per gallon as Ethanol. So even though you're getting 20MPG on Diesel(just as an example) or BIODiesel, on Ethanol in a similar sized Diesel engine you would get closer to 10MPG.

But If Diesel gets you .89:1 Energy balance and Ethanol Gives you 1.3:1 which is really better? Ethanol can sell for $2something a gallon and Diesel here sells for almost $3 a gallon. Naturally it doesn't makes much sense to pay $4 to go the same distance as Diesel when you can run BioDiesel and pay even less or the same as PetroDiesel. So I don't think it really matters unless you have other goals in mind which fuel is better. Ethanol engines are cheaper up front than Diesel either way and with more undersized high compression turbo engines we could see some competition with Diesel in the Daily Driver market. Diesel just recently switched over to low-sulfur fuel and has been marketed more for the fuel economy minded. But watch for the day Diesel hits $4 a gallon. Even then Ethanol will still be $2 a gallon.

My whole argument here is that Ethanol is on par with Diesel for thermodynamic efficiency. The fuel efficiency is less due to energy content but you're not losing energy, just volume and weight. Ethanol is Renewable, Diesel is not. We're not discussing eliminating any fuel entirely, except some might argue for Ethanol's dissolution. I think there is a good enough argument for increasing Ethanol usage among vehicles.

Now with Biodiesel, I think this is a good thing recycling and gaining fuel from otherwise trashed vegetable oils. But it's even more resource restricted than Soybean Biodiesel. There have been reports of Ethanol/Diesel mixtures having positive effects on emissions. And Ethanol can be run in a higher compression Diesel engine or even used as an additive in regular Diesel. Enough to suggest that Soybean Biodiesel isn't necessarily the only route for renewable fuel or fuel additives in regards to Diesel. Diesel isn't going to be dismissed by Ethanol based fuel it can be embraced. Where weight is less of an issue such as commercial trucks and buses a Diesel powered vehicle is often the only way to efficiently transport people and products. Those vehicles can be run on Ethanol but once you switch fuels completely just like going Gasoline to Ethanol engine it's expensive switching back. Flexfuel Vehicles are the worse example of Ethanol power plants you can find. If you saw the benefits of alcohol based fuels I think you all would like the gains that can be made by providing at least one common sense alternative fuel.

[solarguy]

So, yes. If we make ethanol (very efficiently) from a feedstock that is not corn, and grows on marginal land (efficiently) and it's used fairly locally (for efficiency in the distribution system), and burned in a car that is purpose designed for it, for maximal efficiency, ethanol can play a small role in the future solution.

It will not, under any imaginable circumstance, just allow us to carry on with business as usual in big fat inefficient vehicles. Not that anyone in this conversation is suggesting or advocating this.

Part of my reason for being suspicious about pro-ethanol arguments, is that so many necessary pieces of the puzzle are just not there yet. Further, GM and Ford used (and are still using) Flex fuel vehicles to get a big fat juicy pass from CAFE regs, so they could just keep right on building big fat inefficient Suburbans while getting green-washed. They could just use an arbitrarily and suspiciously high FE number for every flex fuel Suburban they sold to calculate their CAFE numbers. Similarly, I am suspicious of the 1.5:1 number from the Dept of Ag people. They are not an unbiased and independent 3rd party. I will have to dig a bit deeper into how they do the math and account for all the external issues.


Smart ethanol + 57 other strategies, OK, now we have a chance.

When the average car for sale in the US gets ~50 mpg, and the average american consciously cuts the number of miles driven by 50%, we're in the game.

Finest regards,

troy

[Allch Chcar]

Originally Posted by solarguy

troy

If we did what you say, Ethanol could fuel a large part of our vehicles. Not like it does now.

The Dept of Ag people are the most "unbiased" source you're going to find. Which isn't much considering the political climate, there aren't really many unbiased sources. But you have to remember the Dept of Ag isn't CARB or ADM. They're don't have any stake in Ethanol production they just measure input-output and go from there. The 1.5 figure is state-of-the-art, 1.3 is average from what I've found, while .89 is Gasoline energy input-output. If there was a better way to produce Ethanol the Dept of Ag would probably be promoting it don't you think? Not unless there is some tie to ADM that can be found.

Flexfuels are greenwashed. Calculating MPGe with gasoline when you're also burning ethanol but usually burning regular gasoline is a terrible way to promote something. They are also EXACTLY as efficient at burning Ethanol as a Regular Gasoline car. The only way the could get any better was lean burn, which isn't likely since Gasoline is more susceptible to detonation and limited on load running lean burn.

Despite what you say Ethanol has already been a major factor in fuel usage even with the little percentage they're mixing. Have you noticed that the price of fuel is still comparatively low? For the same amount of skepticism perhaps you should work on your own diesel fuel efficiency thread. Afterall Diesel's fuel efficiency is from running lean at part throttle, low rpm events. Ethanol can perform the same level of lean burn at part throttle to get similar thermodynamic efficiency. The only disadvantage ethanol has is the lower energy content per gallon. It beats out Gasoline and the requirements can be loosened with Ethanol vs Diesel on engine size. Just like a Diesel, Ethanol can run a turbo for added power even on a production car. The production of Ethanol from Corn hasn't peaked either due to the demand being so low. Diesel production peaked here in the 80's.

After Ethanol production fulfills enough to meet the 10% requirement of Ethanol in Gasoline there isn't much demand to speak of between Flexfuels and Car modders running E85 for Ethanol to really go anywhere.

[Stormin' Norman]

First of all, I must say that I'm impressed by the depth and scope of knowledge among you folks. Humbled in fact.

A comment on the first page of this thread mentioned knock sensors and dynamic timing systems, obviously on a vehicle with an On Board Computer. Well, my car was built on the Cusp of OBD technology in 1979, and unlike the same car built in the US or Canada, the Mexican Ford factory used an old-school points ignition on my old 302 V8. I was tired of 16 MPG and swapped the engine with a freshly built 3.3L stock Ford Fairmont six with the Electronic Ignition and get upwards of 22 MPG. Still no computer.

My plan is to drop in another stock 2.3L I4 Turbo with a standard transmission (my wife will not drive an Automatic, PERIOD). To do that, I would buy a complete, running 1989 Tbird Turbo Coupe or Mustang/Capri from around the 1987 to 1989 era. I've already wired a Mustang dash into my Fairmont (basically identical, except with gauges, not idiot lights) and added a vacuum gauge, voltmeter, and a 1984 Cougar clock. The clock doesn't sound like much, except that the 1984 Cougars and post 1984 Mustangs came with OBD II systems. The Speedo has a trip meter, so I can track my MPG and FE.

I never considered Ethanol with as much depth as you folks have, but I knew a Turbo would be more efficient.

As someone mentioned earlier, about the Ford Focus weighing 2,600 lbs. My 1979 Fairmont Squire wagon, all fueled up with the I6 weighs 2,645 lbs. Its in the weight zone. As a Mexican car, it had no rust, when I did a complete restoration in 2006 and 2007, and is even better protected against rusting, after all that. I expect another 10 years of daily service, and it won't be near as bad as the 1978 donor car was 4 years ago - no floors, no tire well.

Would Ford be my best bet for the knock sensors and dynamic timing components or are their better aftermarket sources? Thanks in advance.

[oldman]

been doing pen and paper MPG for 35 years. Gotta Civic HX as a puttputt, has a VTEC-E lean burn engine, used to get 41 to 43 MPG over tens of thousands of miles, same job, same home. With the switch to 10% ethanol I'm at about 36 MPG... that is a massive drop. My other cars have also dropped by say 3% to 5%, they are newer cars BTW. The Civic goes into lean burn when a set of conditions are met and the A/F is closely watched via 5 wire wide band 02s. My thinking is the engine never goes into lean burn anymore cause it is already running lean. The VTEC goes from 12 valve lean burn to 16 valve power mode and that still works, all the normal things have been checked over and over like pumping compression, timing, fuel pressure, EGR ports, back pressure in the exhaust. I can only conclude my economy car really does not function well on 10% booze. I do. I should note the power is down too. This is a high geared small engine and the drop in power is noticeable, it is almost like running the A/C all the time.

My Challenger is down about 3% in MPG, and my Volvo is down about 3% also, my turbo Volvo seems to like 10% booze, but it is chipped and has other performance mods so it maybe using the extra octane. dunno.