RSS Feeds
Auto Industry Redesigns Engines While Ethanol Debate Rages
E85 engines are on their way, but some still question the value of ethanol
Charles J. Murray, Senior Technical Editor -- Design News, July 16, 2008
In essence, it’s grain alcohol. Moonshine. Hooch.
But this hooch is about to change the way we power our vehicles. Ethanol, as it’s better known, has emerged as a key part of the national energy debate. It’s seen as a solution to a variety of ills, ranging from high gas prices to global warming to an unquenchable thirst for foreign oil. As such, farmers, politicians and auto executives are calling for accelerated production of it.
“We believe that sustainable biofuels are the right way to go,” says General Motors Spokesman Alan Adler. “That’s why we’ve committed to making half of our U.S. production E85-capable by 2012.”
Indeed, GM says it already has 3 million E85 vehicles (capable of burning a blend of 85 percent ethanol, 15 percent gasoline) on the road today and by 2012 it plans to be cranking out 2 million of them a year. Similarly, Ford Motor Co. has pledged that it, too, will make half its production vehicles capable of running on alternative fuels by 2012 and virtually every other global automaker has similar plans for a stable of flex fuel vehicles.
Much of the motivation for this migration to ethanol stems from the Energy Independence and Security Act of 2007, which the U.S. Congress signed into law last December. Among its many provisions, the Energy Act calls for production of 36 billion gal of biofuels by 2022, up from 4.7 billion gal in 2007. Fifteen billion of those gallons will come from corn, while the rest will be derived from other sources such as sugarcane and possibly even trash and old tires.
To be sure, not everyone is in lock step on this topic. Some studies contend the corn-to-ethanol process is a waste of effort because it burns nearly as much energy as it creates. Others argue that corn is just a bridge to a more energy-efficient fuel known as cellulosic ethanol.
What it all means is, well … chaos, if just a mild case of it. While environmentalists and economists argue over ethanol’s relative merits, engineers are charging ahead with new engine designs and farmers are re-configuring their croplands, at least until a better solution emerges.
“We know that gasoline and food prices are going to stay high,” says John Caupert, director of the National Corn-To-Ethanol Research Center in Edwardsville, IL. “So the question is this: Do you want to send your hard-earned U.S. dollars to a Saudi prince or an American farmer? Ethanol gives you that choice.”
Engines Get a Makeover
The fact that ethanol has emerged as a solution to our energy ills is no surprise. It received brief attention as an alternative form of energy during the 1970s oil embargo. Various forms of it were also used to power Ford and diesel vehicles a century ago. As a result, the current methods of ethanol production are well-recognized and accepted.
“For the most part, we’re converting starches into sugar and then into alcohol in the exact same manner that we’ve used since the beginning of time,” Caupert says. “What’s changed is that the process has been made simpler, more efficient and more cost-effective.”
For automakers, the downside of ethanol is that it will require changes in their engine designs. Because ethanol is corrosive and burns at higher compression ratios than gasoline, some components will need to be upgraded; a few will have to be added. Fuel pumps and fuel level sensors, for example, will almost certainly need to be made more robust to stand up to the rigors of alcohol. Some fuel tanks and fuel lines might need to be swapped out, as well, depending on their current make-up.
“Plastic fuel tanks don’t mind E85,” says Coleman Jones, biofuels implementation manager for GM. “But a turned metal fuel tank typically isn’t very happy with it.”
Jones says fuel rails will also need to be upgraded on some vehicles, along with cylinder heads. All engines, he says, will need a change of fuel injectors.
GM and other car makers typically re-write their engine control software, too. The new software is responsible for recognizing whether the car’s burning gasoline or ethanol, which isn’t always easy. Using the existing oxygen sensor in combination with a special software algorithm, the ECU can “see” that the air-fuel ratio has changed and therefore can differentiate between the presence of ethanol and other possibilities, such as an air leak or a weak fuel pump.
“The vehicle doesn’t ‘know’ it’s looking at ethanol,” Jones says. “All it knows is that the air-fuel ratio is changing.”
Fuel changes also lead to altered operating parameters, because ethanol requires different cold-start characteristics, as well as spark timing and exhaust gas recirculation.
For automakers, all of those changes will add up to more than $100, possibly as much as $150.
“In a low volume vehicle, the costs will be a little higher,” Jones says. “With a high volume vehicle, you can spread the costs out a little more.”
Energy-Efficient?
The real question, however, is whether ethanol is an efficient alternative to gasoline. Some experts contend that each gallon of corn-based ethanol burns nearly a gallon of fossil fuel during its own production. Much of that fossil fuel is used during the distillation process, but heavy diesel-burning farm machinery accounts for some of the energy loss, as well.
Most experts estimate it takes 1 gal of fossil fuel to create 1.3 gal of corn-based ethanol, but a few have claimed the process burns more energy than it creates. “Most estimates leave out the energy from farm labor, the energy to make and manufacture the tractor and the energy required for irrigation,” says David Pimentel, a Cornell University entomology professor and a former advisor to the White House on environmental issues. “By omitting nearly half of the inputs, they’re able to demonstrate that the corn plant is collecting more energy than it takes to make the ethanol. But it just isn’t true.” Pimentel estimates the corn-based ethanol process actually burns about 1.43 gal of oil equivalent to produce 1 gal of ethanol.
Ethanol advocates claim such studies are wildly inaccurate. “When you separate the wheat from the chaff, you’ll find that those estimates are based on 20-year-old data,” argues Caupert of the National Corn-To-Ethanol Research Center.
Cellulose Heats up
Still, the energy balance is close enough to a wash that it’s caused many experts to look at alternative feedstocks, such as cellulose.
“The cellulosics have an energy balance of about seven or eight to one, which is very attractive,” says David Cole, director of the Center for Automotive Research. “The cost is also about a dollar per gallon, which is also very attractive.”
Companies such as Coskata Inc. are trying to capitalize on the advantages of cellulosic ethanol by developing production processes with high likelihoods of success. Coskata claims it can create ethanol by using such feedstocks as wood chips, municipal waste, trash or old tires. The company’s method seems simple: It decomposes carbon-based materials into their organic components in a step called gasification. Once “gasified,” the feedstocks are broken down into ethanol and water inside a bioreactor filled with patented microorganisms (yes, microorganisms can be patented). After distilling, pure ethanol is leftover.
Still, the process is far more daunting than it looks at first glance. Coskata’s method depends on the presence of the microorganisms or “bugs.” Discovered by a University of Oklahoma professor, the bugs are naturally occurring organisms similar to bacteria and they reportedly can chew up any amount of synthesis gas, or “bug food,” and turn it into ethanol. Coskata engineers say the discovery of the bugs took decades.
“Someone might spend an entire lifetime trying to find organisms like these,” says Wes Bolsen, chief marketing officer for Coskata.
GM executives who viewed the technology late last year were so encouraged that they partnered with Coskata as a way of hastening the construction of a production plant. Coskata expects to have a 100-million-gal-a-year production plant up and running by 2011. Although the company’s efforts to date have involved limited production, Coskata executives say they’re confident the $400 million plant will easily scale up to greater production levels.
“It’s not like we’re looking for massive inventions or major breakthroughs to make this work,” Bolsen says. “We’re going to use technology that’s commercially available today.”
The Debate Rages
To be sure, some experts have no more faith in cellulosic than they have in corn-based ethanol. They say cellulosic technology is unproven, largely because there’s not a single commercial plant in the world that’s converting cellulose to ethanol, despite the large sums of seed money behind it.
“Despite all the research, there’s no evidence that cellulose is going to be profitable in terms of energy or economics,” says Pimentel of Cornell. “There’s a lot of hope, and I like the hope myself, but we haven’t seen results yet.”
Ethanol proponents point out that the corn-based product is important for those exact reasons. “It’s pretty clear that feedstocks such as corn are charting the path,” Caupert says. “They’re paving the way for cellulose feedstocks to follow.”
Proponents also point to Brazil as an example of ethanol’s success. There, a state-subsidized switch to ethanol enabled the country to kick the foreign oil habit nearly 30 years ago. Many U.S. auto executives who saw the transformation are believers in ethanol.
“The idea of working towards an alternative fuel made a lot of sense to us partly because so much of our senior leadership had worked in Brazil,” says Adler of GM.
That may be why GM, Ford and others have already committed so much effort toward the ethanol switch. In 2009, GM will broaden its E85 lineup to include cars, as well as trucks, as it rolls out the four-cylinder Chevy HHR and the Buick Lucerne.
Ford Motor Co. already has 14 flex-fuel models on the road and its 5.4-§¤ Triton V-8 engine is E85-capable. In addition, its Volvo ReCharge plug-in hybrid concept car promises to use a Flexifuel engine, as well.
In the end, though, the fate of ethanol will depend on a number of variables, ranging from Middle East stability to the price of imported oil to society’s commitment to the reduction of greenhouse gases.
“As a nation, we’re embroiled in an energy debate,” Caupert says. “The consumers will have a choice to make. It’s just a matter of where they want their dollar to go.”
Gallery »
Auto Industry Redesigns Engines While Ethanol Debate Rages
E85 engines are on their way, but some still question the value of ethanol
-
For the Concerned Citizen, my impression of why the E85 mileage is so poor, may be that the Auto manufactures did not make modifications that can use the advantages of Ethanol to reduce or eliminate the loss. A college group took a stock vehicle and modified it to run off E85, and achieved greater MPG (they made many changes, at a cost). Yes, there are differences in BTU output, but we are not burning the fuels, as in propane versus natural gas, but we are exploding the fuel to create pressure to push . . . etc. In round numbers, about 1/3 of the energy is lost out the exhaust, 1/3 is lost to heat (radiator), and 1/3 is used to propel the vehicle. Although the BTUs are lower, you are not using all of the BTUs to power the vehicle. This makes the difference less then the BTU delta. I personally found that I can use 20% - 35% E85 in my 1984, I-4, Automatic and achieve a 1 - 3 MPG increase (I do not recommend that anyone use E85 in non-FFV).
Kevin Giardini - 2008-30-7 10:55:18 EDT -
I agree that this is a well written article, and some research was done (as opposed to writers that write what they 'think' without references). This would be a good article if it were written many years ago, but it is a little lacking for today's technology. I think hooch has powered vehicles since Henry Ford days. If GM already has 3 million vehicles on the road today, they have already made the changes that this article leads you to believe are still needed: They already make fuel pumps, fuel level sensors, fuel tanks, fuel lines, fuel injectors, engine control software, and not only do they make ethanol sensors, but a newer version that can distinguish 2% mixtures is available. So the FFV vehicles "do" know they are burning ethanol (unlike my 1984 that can not). Corn-to-ethanol has been shown to yield slightly more than it takes to produce (net gain), which can not be said about petroleum. I'm glad that you later explain what cellulosic ethanol 'is', or you could mention that cellulosic ethanol can be produced with the 'other' parts of corn (stalk) rather than the 'food' portion. If distillers think ahead, the grain can go down one line while the stalks and leaves go down the other. Energy-Efficient? What energy is required (expended) to drill, pump, transport, store, 'crack', distribute, etc. petroleum? If gasoline sells for $4 and Ethanol sells for $3, this gets you closer to which is more cost effective (unless gas is so profit overpriced). Your article states that Ethanol yields 30% more energy (1 gal of fossil fuel to create 1.3 gal of corn-based ethanol). There is one version, I am not sure that it is cellulosic, called Bio-Butanol, that is made in smaller quantities today, but the cellulosic ethanol that you speak about should be more efficient to produce than Butanol. GM also makes a Brazilian car that runs off 100% Ethanol, with a small reservoir that contains gasoline, which is used during the first few seconds while starting the car, then switches to the Ethanol (why are these vehicles not sold here?) GM also made (makes) a Methanol fueled vehicle that was (is) sold in California. I believe it can run on either M85 or E85.
Kevin Giardini - 2008-30-7 10:33:08 EDT -
"ethanol burns at higher compression ratios than gasoline"
Not exactly! Ethanol burns BETTER at higher compression ratios than gasoline, because it has a very high octane rating.
Ethanol does take a lot of energy to produce. The trick is to use energy sources that can't be used in cars to produce ethanol, which can. Why is nobody using solar heat to distill alcohol? I know it has been done in the past, there was a US corn farmer whose solar still was confiscated by the ATF.
James L - 2008-30-7 07:17:41 EDT -
