بیوتکنولوژی صنعتی Industrial Biotechnology

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بیوتکنولوژی صنعتی Industrial Biotechnology

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Myths & Realities: Diesel/Biodiesel

1. All vehicles with diesel engines spew a dark black trail of noxious fumes.

Many Americans have not shed the mental image of diesel cars as an environmental nightmare. This partly explains why diesel vehicles account for only about one percent of new car sales in the United States. It's interesting to note that diesel vehicles in Europe-where by most accounts everything is greener-now account for nearly half of all new vehicle sales. The reality about diesel lies somewhere between Americans' reluctance and Europeans' nonchalant attitude about diesel emissions.

When it comes to greenhouse gas emissions, diesels get high marks. There is a one-to-one relationship between greenhouse gas emissions and fuel efficiency. Because diesels are more efficient than conventional cars, they generate less carbon dioxide (the primary culprit for climate change.) However, diesels emit larger amounts of two other pollutants:

  • Particulate Matter: Diesel particulates are harmful to human health as well as aesthetically unpleasing.
  • Oxides of Nitrogen : While less visible, NOx is a key ingredient in the formation of urban smog, and also can contribute to the formation of acid rain.

Are these pollutants a big deal? According to the California Air Resources Board, they are. Currently no new diesel passenger vehicles can be sold in the five states that adhere to the more stringent California requirements: California, Massachusetts, Maine, New York and Vermont. The current diesel Liberty, Beetle, Golf and Jetta, in other words, are 45-state vehicles. For 2007 models, only one 50-state diesel car is on the horizon--the new Mercedes E320 BLUETEC to be introduced in late 2006. The 2007 E320 BLUETEC has NOx emissions that are more than eight times lower than the outgoing 2006 E320 CDI.

2. It's hard to find diesel fuel.

Finding fuel for diesel vehicle doesn't require desperate excursions to the truck stop on the edge of town. It only requires a little careful attention to which of your neighborhood filling stations offers diesel. Nearly half of the 180,000 gas stations in the United States serve up diesel to their customers.

3. Using biodiesel in a diesel engine requires a special conversion.

Biodiesel should not be confused with straight vegetable oil, which is untreated oil that some people use as fuel in their modified diesel cars. Biodiesel--a renewable fuel derived from plant oils or animal fats--is a more standardized product that can be used in most diesel engines without any modifications. (Like conventional diesel fuel, biodiesel can only be used in diesel engines.)

Biodiesel can be used in its pure form, which is called B100 (100 percent biodiesel), or can be blended in any proportion with conventional diesel fuel. Common blends include B20 (20 percent biodiesel and 80 percent conventional diesel), and B5 (5 percent biodiesel and 95 percent conventional diesel). According to the Department of Energy, 431 fueling stations in the United States offer commercial biodiesel, although many of these locations sell only low-level blends.

The inconvenience may not be such a big issue--if you're comfortable with switching back and forth from petroleum diesel and biodiesel, or if you're willing to take a do-it-yourself approach. Unlike any other fuel for modern engines, biodiesel can be made at home without investing heavily in special equipment or earning a degree in chemistry. Is biodiesel worth the inconvenience or the extra work? That depends how strongly you feel about using a renewable fuel that can be produced domestically.

Biofuel

Biofuels Are Promising But Would Require a Major Shift

Biofuel or biomass energy are formal names for fuel created from stuff that can be grown. The most common forms of biofuel are ethanol (derived from sugarcane or corn) and biodiesel (fuel made from natural, renewable sources such as vegetable oils). Creative alternative energy folks have also used everything from livestock droppings to heather, and look to perennial crops like switchgrass and poplar trees as low maintenance sources. Just imagine a society fueled with clean, renewable, locally grown fuel.

In addition to providing a renewable source of energy for our transportation needs, and thus reducing greenhouse gases and dependence on foreign oil, biofuels could provide tens of millions of dollars of new income for American farmers and rural communities.

Biodiesel Benefits

  • Biodiesel runs in any conventional, unmodified diesel engine
  • Biodiesel can be used alone or mixed in various percentages with petroleum diesel
  • Biodiesel can be stored and transported anywhere that petroleum diesel is stored (with little or no damage in the event of a spill). It’s biodegradable and non-toxic.
  • Engines running biodiesel have similar fuel mileage to engines on diesel fuel

On the negative side, biodiesel produces more nitrogen oxide, which contributes to smog. In addition, pure biodiesel does not flow as well as petroleum diesel in cold temperatures, so it could result in increased engine clogs.

Singer Willie Nelson began selling his own blend of biodiesel, which he calls BioWillie. It's part of his campaign against the Iraq War and in support of American farmers. Daniel Becker, the Sierra Club's global warming expert, believes the process of producing biodiesel is too energy intensive, resulting in a washout in terms of conservation. He told the New York Times, "If you're going to the trouble of using an alternative fuel, use a good alternative fuel. If you really want to listen to Willie Nelson, go buy one of his records and play it in a hybrid."

Ethanol Benefits

  • Up to a 10 percent blend of ethanol is already covered under warranty of every auto manufacturer
  • A blend with 85 percent ethanol burns in an extremely clean and complete manner
  • E85 is already running on millions of so-called E85 flexible cars in the U.S. These cars, primarily used in corporate and government fleets, are manufactured by DaimlerChrysler, Ford, GM and Mercedes. Most of the E85 flexible cars are wagons and pick-ups.
  • The biggest drawback with high-ethanol blends today is that they are not widely available. The U.S. has nearly 170,000 gasoline stations; approximately 600 offer ethanol. It took 15 years to switch over from leaded to unleaded gasoline.

Major Shift Required

A grow-your-own approach to fueling our cars and trucks sounds very enticing. A major shift to biofuels could put our farmers to work, greatly reduce greenhouse emissions, and free us from dependence on the Middle East. A shift to a biofuel infrastructure would not happen overnight. It would require a major shift in our collective political will.

This potential shift also raises serious concerns about land use, pesticide use, and genetically modified crops, as well as difficult economic questions about the net costs of using land for food production versus energy production.

Hybrid cars by definition use more than one source to power a car. As a result, hybrids are often referred to as a bridge technology between currently available technologies and promising future approaches, such as hydrogen fuel cells. As carmakers continue to improve gas and diesel engines, and experiment with hybridization, perhaps biofuels will be brought into the mix—but only if oil becomes more scarce, more costly to produce and import, and even more obviously destructive to the environment.

Diesel - Overview

Diesel vehicles now account for nearly half of all new vehicle sales in Europe. In some European countries (such as France), diesel vehicles account for as much as 70 percent of new car sales. Are diesel vehicles a viable alternative to hybrids?

 

 

For a 2007 or later model year, diesel passenger car to be sold in all 50 states, it must meet tougher emissions requirements. there is only one T2B5-compliant, 50-state diesel car on the horizon—the new Mercedes E320 BLUETEC to be introduced in late 2006.

 

The Diesel Difference

Diesels are also known as compression ignition engines, and have a different combustion cycle than gasoline engines. In a gasoline engine, fuel is sprayed into the cylinder, mixed with air, and ignited by a spark from the spark plug.

In a diesel, air is drawn into the cylinder and compressed first without fuel present. This compression heats the air to such a high temperature that when fuel is then injected into the cylinder, it combusts. By using higher compression ratios and higher combustion temperatures, diesels operate more efficiently. As a result, diesel vehicles attain better fuel economy than their gasoline counterparts. This fuel economy advantage is enhanced by the fact that a gallon of diesel fuel contains about 10% more energy than a gallon of gasoline. These two factors help modern direct-injection diesels achieve roughly 50% higher fuel economy than their gasoline counterparts. For example, a European model Honda Accord with a 2.2 liter i-CTDi diesel engine is rated at 43.3 MPG, 49 percent higher than the rating of a Honda Accord with a 2.4 liter gasoline engine. The Camry Hybrid is rated at 39 MPG, 10 percent lower than the diesel Accord.

Diesel Emissions

Modern diesels require something of an environmental tradeoff. While generating fewer greenhouse gas emissions (due to greater fuel efficiency), diesels emit larger amounts of two other pollutants:

  • Particulate matter is the black cloud that trails many older diesel vehicles. Diesel particulates are harmful to human health as well as aesthetically unpleasing.
  • NOx, while less visible, is a key ingredient in the formation of urban smog, and also can contribute to the formation of acid rain.

Higher emissions of these pollutants are diesels' greatest drawback. There has been an ongoing split in diesel emissions regulations in the US between those required by the Environmental Protection Agency, and those required by the California Air Resources Board.

Currently no new diesel passenger vehicles can be sold in the five states that adhere to the more stringent California requirements: California, Massachusetts, Maine, New York and Vermont. The current diesel Liberty, Beetle, Golf and Jetta, in other words, are 45-state vehicles. The EPA, however, is tightening its diesel emissions requirements, and moving them more into alignment with the California requirements. The point at which the two map exactly for passenger cars is called Tier 2 Bin 5 (T2B5).

For a 2007 or later model year diesel passenger car to be sold in all 50 states, it must meet the T2B5 emissions requirements. Currently, there are no T2B5-compliant, 50-state diesel cars. One is on the horizon—-the new Mercedes E320 BLUETEC, to be introduced in 2007. BLUETEC refers to the emissions after treatment system that enables the vehicle to meet the T2B5 standard. The 2007 E320 BLUETEC has NOx emissions that are more than eight times lower than the outgoing 2006 E320 CDI

 

 

Not an Either-Or Situation

It's technically possible to use a hybrid drivetrain with a diesel engine. In fact, PSA Peugeot Citroën recently showed a diesel-hybrid prototype: the 307 CC Hybride HDi, a compact convertible that gets 70 miles per gallon, about 30 percent better fuel economy than the existing diesel version. No one makes diesel hybrids yet, mainly because they are expensive. The added benefits come at a double expense—more for the hybrid system and more for the diesel engine. PSA Peugeot Citroën may introduce a diesel hybrid to the market as early as 2010. But no promises yet from the company.

Pros and Cons of Ethanol

The Upside of Ethanol

Proponents of ethanol emphasize its environmental and energy security benefits.

  • Ethanol is a renewable fuel that comes from agricultural feedstocks, and thus can be produced domestically.

 

Using ethanol made from corn instead of gasoline would lead to a moderate 13 percent reduction in greenhouse emissions. Using cellulosic ethanol from feedstocks such as switchgrass, pictured above, could result in 88 percent less greenhouse gas emissions. (Photo: National Renewable Energy Lab.)

Using ethanol (particularly E85) also results in less pollution, reducing smog-forming emissions by as much as 50 percent relative to gasoline. E85-powered vehicles also contribute to global warming, although experts disagree about just how much greenhouse gas is emitted by using ethanol.

One might expect that by using E85, net carbon dioxide emissions would be almost zero. The crops used to make the ethanol absorb CO2 from the atmosphere during their growth, then this CO2 is put back into the atmosphere when the ethanol is burned in an automobile engine. In reality, this cycle is overly simplistic because it fails to recognize other greenhouse gas emissions that occur during the cultivation and production of ethanol. Modern farming, for example, relies heavily on diesel-powered equipment that emits greenhouse gases. Distilling ethanol is also an energy-intensive process that often uses electricity generated from coal, another source of greenhouse emissions.

Researchers at the University of California at Berkeley recently examined six major studies of ethanol production and concluded that using ethanol made from corn instead of gasoline would lead to a moderate 13 percent reduction in greenhouse emissions. However, the researchers note that more dramatic reductions are possible if technology advances make it economical to make ethanol from cellulosic materials such as switchgrass, a crop currently grown by some U.S. farmers to control erosion on idle fields. Using cellulosic ethanol, they project, could result in 88 percent less greenhouse gas emissions.

The UC Berkeley study also contradicts a common criticism of ethanol: that it takes more energy to produce it than it delivers as a motor fuel. The study concludes that ethanol made from corn does indeed have a positive “net energy balance,” particularly if you consider that other valuable products, such as corn oil, are byproducts of the ethanol-making process.

The Downside

E85 may be better for the environment and the American farmer, but it has some drawbacks.

  • The first is price: ethanol can be more expensive than gasoline, depending on where you live. Data on fuel prices from the DOE shows that in the Midwest (where much of the country’s ethanol is produced) E85 sells for nearly 30 cents less per gallon than conventional gasoline. However, on the West Coast, filling up with ethanol would cost a driver 35 cents more per gallon. In the mid-Atlantic states, E85 had an even higher premium: 44 cents per gallon.
  • The higher price of E85 in many areas is made worse by ethanol’s second drawback: ethanol, regardless of the price you pay for it, contains less energy than gasoline. This means that your car won’t go as far on a gallon of E85, and your fuel economy will decrease by 20-30 percent. This is bad news for consumers because even if the price of E85 at the pump is cheaper than gasoline, using ethanol may not be less expensive in the end.

Let’s consider one example. The most fuel-efficient flexible-fuel vehicle available this year is the Chevrolet Impala. Using gasoline, it is rated at 21 mpg in the city and 31 mpg on the highway. By using E85, rated mileage drops to 16 mpg city and 23 mpg highway.

If you fill-up the Impala’s 17-gallon tank at a station in the Midwest, you’ll save $5.10 by using E85. So far, so good. However, you can’t drive as far on E85 and will have to refuel sooner than if you had purchased conventional gasoline. In fact, your cost per mile is higher using E85: 9.7 cents/mile vs. 8.4 cents/mile for regular gas.

A 1.3 cent per mile difference may not seem like much, but over the course of a year’s driving it adds almost $200 to your fuel costs.

  • Another other issue is that E85 is widely available only in the Midwest. The DOE lists more than 600 E85 stations in the United States, but nearly half of those are in two states: Minnesota and Illinois. Other areas, even populous ones, have little E85 infrastructure. For example, New York, California, Texas and Florida have just 15 E85 stations combined, only two of which allow sales to the general public.

To put things in perspective, there are more than 150,000 stations nationwide selling gasoline. While all of them may not need to offer E85, it is clear that wider distribution is needed before E85 can begin to displace gasoline sales

Ethanol or Gas

Illustrations by Joe Goebel

Millions of clean-running alternative fuel vehicles are plying American roads, ready and waiting to fill their tanks with ethanol fuel. These are flexible-fuel vehicles, or FFVs, marketed by Ford, General Motors, DaimlerChrysler, Isuzu, Mazda, and Mercedes-Benz since the late 1990s. FFVs are so-named because they can operate seamlessly on any mixture of E85 (a blend of 85 percent ethanol and 15 percent unleaded gasoline) or straight unleaded gasoline from the same tank.

Ethanol, or ethyl alcohol, is a clean burning fuel typically produced from corn, although other grains like wheat or barley can also be used. These feedstocks are abundantly available in this country. Besides its advantages as a renewable and domestically available biofuel, ethanol combustion in engines also results in modest reductions of harmful hydrocarbon and benzene emissions, as well as reduced carbon dioxide, a greenhouse gas.

Hmmm… domestically produced by American farmers and producers, lower emissions, and a huge number of vehicles with tanks a-waiting. So why is there such a monumental disconnect that finds millions of FFVs on the highway and only about 175 stations nationwide where drivers can fill up on E85?

This dichotomy is good example of what can occur when technology outpaces society’s ability to apply its use, in this case primarily due to economics and, unfortunately, politics. It’s also an example of how government incentives and subsidies can have unintended consequences. Lessons learned from the FFV experience should be examined and applied as the nation embarks on a path that will find us potentially using a much more technically challenging and expensive alternative fuel: hydrogen.

The dilemma can be traced directly to the Alternative Motor Fuels Act (AMFA) passed by Congress in 1988, a law that gives automakers incentives to develop and market vehicles that use fuels other than gasoline. Manufacturers can receive a credit of up to 1.2 miles-per-gallon for each FFV produced that can be applied toward meeting their Corporate Average Fuel Economy (CAFE) requirements. Unfortunately, there is no corresponding incentive to encourage development of a refueling infrastructure, which brings us to the nearly nonexistent E85 refueling infrastructure today.

Establishing an E85 infrastructure presents a significantly larger challenge than getting engines to run well on E85. Since alcohol fuels like ethanol cannot be moved readily through existing petroleum distribution pipelines, it must be transported by barge, rail, or truck. Contrasting this, modifying an engine to run on E85 is not that difficult, requiring a fuel sensor for detecting the real-time ratio of ethanol to gasoline being supplied to the engine at any given point in time and optimizing engine and fuel settings for this mixture. Items like stainless steel fuel tanks, Teflon-lined fuel lines, and modified injectors must also be used to ensure compatibility with ethanol since it’s a much more corrosive fuel than gasoline.

From a vehicle standpoint, the AMFA incentive is a resounding success. Manufacturers driven by the additional CAFE credits made more than a million FFVs last year and expect to produce twice as many in 2004.

Chevrolet Silverado, 5.3-liter V-8

Chevrolet Avalanche, 5.3-liter V-6

Chevrolet Suburban, 5.3-liter V-8

Chevrolet Tahoe, 5.3-liter V-8

Chrysler Sebring, 2.7-liter V-6

Dodge Caravan and Grand Caravan, 3.3-liter V-6

Popular models that can run on gasoline or E85 range from the Ford Explorer and Chevrolet Silverado to the Dodge Stratus and Mercedes-Benz C320. These vehicles are available in many, but not all, states, so check with your local dealer or your dealer’s fleet department to confirm availability in your area.

Still, while the vehicle end is a success, all this has not accomplished the AMFA’s primary intended goal of reducing the nation’s dependence on imported oil, not to mention significantly decreasing C02 emissions. According to the National Highway Traffic Safety Administration (NHTSA), extending these credits without expanding the availability of E85 actually increases petroleum consumption and greenhouse gas emissions. That’s because FFVs operating almost entirely on gasoline effectively decrease the CAFE for this FFV fleet by about 1.2 mpg. The credits given for the unused ethanol equates to somewhere between 20 to 56 million additional barrels of oil used annually.

Dodge Ram, 4.7-liter V-8

Dodge Stratus, 2.7-liter V-6

Ford Explorer, 4.0-liter V-6

Ford Exlporer Sport Trac, 4.0-liter V-6

Ford Taurus, 3.0-liter V-6

GMC Yukon, 5.3-liter V-8

Several solutions to this so-called CAFE loophole have been proposed. One calls for Congress to amend the existing AMFA law to only allow CAFE credits when automakers can certify that their AFVs actually use the alternative fuel. In effect, though, this would penalize the auto industry unfairly since automakers have done their part in developing and marketing FFVs. This strategy could potentially sour automakers’ interest in all AFVs and drastically reduce future investment in other fuel alternatives including hydrogen.

Additionally, if automakers no longer have incremental CAFE credits as an incentive for producing FFVs, they will most certainly stop making them since the incremental cost of making FFVs is now being absorbed in return for the CAFE credits. A more viable solution may be incentives for fuel providers to ensure that adequate fueling facilities are readily available anywhere AFVs are sold. Potentially, this could be federal income tax investment credits for each new alternative fueling site, which would cover most of the cost and thus make establishing these fueling sites attractive.

The infrastructure problem is com-pounded because ethanol is not a petroleum-based product, thus the petroleum industry has shown little interest in offering it. Indeed, ethanol is viewed as a competitor. In the U.S., three producers dominate the ethanol market and the largest, Archer Daniels Midland, controls nearly 40 percent of that market. Because there are so few producers, some fear the potential that supplies could be artificially limited and prices potentially manipulated upward. Additionally, an unintended consequence is that food prices could increase if it turns out that it’s more profitable to convert farm products to fuel rather than food.

GMC Yukon XL , 5.3-liter V-8

GMC Sierra, 5.3-liter V-8

Mercedes-Benz C240 Sedan and Wagon, 2.6-liter V-6

Mercedes-Benz C320 Sedan and Coupe, 3.2-liter V-6

Mercury Mountaineer, 4.0-liter V-6

Mercury Sable, 3.0-liter V-6

The ethanol lobby carries substantial clout in Washington and so has been able to obtain subsidies that distort the true market price of this alternative fuel. Since 1996, crop subsidies alone have been worth nearly $30 billion to the ethanol industry. Ethanol opponents make the case that these subsidies are taking money from taxpayers and giving it to the few ethanol producers, and thousands of corn farmers, without replacing any petroleum or even providing a cleaner fuel. Since ethanol receives a tax subsidy, a gallon of ethanol is taxed 5.3 cents less than a gallon of gasoline, which means that less tax revenue is funneled into the Highway Trust Fund for repairing and replacing roads and bridges. On the other hand, ethanol proponents suggest that with military assets protecting the flow of imported oil, the true price of gasoline is significantly distorted as well.

In use, most people will not be able to discern the difference between driving on E85 and regular gasoline. While ethanol does produce fewer BTUs (less energy) than gasoline, it has a significantly higher octane rating than un-leaded gasoline (100-105 octane versus 85-90). Testing of Ford FFV engines show about a 5 percent increase in horsepower when operating on E85. However, offsetting this is that drivers will notice a 5 to 15 percent decrease in fuel economy, depending on ambient temperatures and driving conditions.

This disparity could be improved if FFVs were optimized for E85, which is presently not the case – another consequence of the absence of E85 availability. Because of lower miles-per-gallon and the now higher per-gallon cost for E85, vehicle operating costs will go up. Currently, ethanol demands higher pump prices because this alcohol fuel is more difficult for refiners to blend with gasoline and also more expensive to ship into areas where corn is not grown.

What could make E85 the fuel of choice for motorists in the absence of government mandates? The best answer is the economics of the marketplace. If the price of gasoline climbs to a point where it equals or exceeds E85, drivers will soon be demanding E85 for their FFVs and traditional fuel suppliers will see a profit in meeting the demand. Such interest could be accelerated by an oil shortage such as a disruption of oil from the Mideast, something this country has seen before.

In a sense, you might even say the millions of FFVs on American roads today are as much an emergency energy resource as the millions of barrels of oil in the nation’s Strategic Petroleum Reserve. That’s food…or rather, fuel…for thought.

Ethanol Myths

1. Ethanol is very rarely used in American cars.

Most likely, you're using ethanol in your car without even knowing it. In many regions, small amounts of ethanol are blended with gasoline to reduce emissions. Mixtures as high as E10 (10 percent ethanol and 90 percent gasoline) are safe for use in most vehicles.

Much of the news lately has been about fuel blends that have higher ethanol content. The most common is E85 (85 percent ethanol and 15 percent gasoline), which only can be used in vehicles that are designed for that fuel.

2. Using ethanol will eliminate global warming.

One might expect that by using E85, net carbon dioxide emissions would be almost zero. The crops used to make the ethanol absorb CO2 from the atmosphere during their growth, then this CO2 is put back into the atmosphere when the ethanol is burned in an automobile engine. In reality, this cycle is overly simplistic because it fails to recognize other greenhouse gas emissions that occur during the cultivation and production of ethanol. Modern farming, for example, relies heavily on diesel-powered equipment that emits greenhouse gases. Distilling ethanol is also an energy-intensive process that often uses electricity generated from coal, another source of greenhouse emissions.

Researchers at the University of California at Berkeley recently examined six major studies of ethanol production and concluded that using ethanol made from corn instead of gasoline would lead to a moderate 13 percent reduction in greenhouse emissions. However, the researchers note that more dramatic reductions are possible if technology advances make it economical to make ethanol from cellulosic materials such as switchgrass, a crop currently grown by some U.S. farmers to control erosion on idle fields. Using cellulosic ethanol, they project, could result in 88 percent less greenhouse gas emissions.

The UC Berkeley study also contradicts a common criticism of ethanol: that it takes more energy to produce it than it delivers as a motor fuel. The study concludes that ethanol made from corn does indeed have a positive "net energy balance," particularly if you consider that other valuable products, such as corn oil, are byproducts of the ethanol-making process.

3. Ethanol is cheaper than gasoline.

Data on fuel prices from the Department of Energy shows that in the Midwest-where much of the country's ethanol is produced-E85 sells for nearly 30 cents less per gallon than conventional gasoline. However, on the West Coast, filling up with ethanol would cost a driver 35 cents more per gallon. In the mid-Atlantic states, E85 had an even higher premium: 44 cents per gallon.

The higher price of E85 in many areas is made worse by another of ethanol's drawbacks: ethanol, regardless of the price you pay for it, contains less energy than gasoline. This means that your car won't go as far on a gallon of E85, and your fuel economy will decrease by 20-30 percent. This is bad news for consumers because even if the price of E85 at the pump is cheaper than gasoline, using ethanol may not be less expensive in the end.

4. Ethanol-ready vehicles are equally available in all sizes.

If you're looking for small, fuel-efficient vehicles that use E85, you may be disappointed. Half of the 2006 flexible-fuel vehicles are full-sized pickups or SUVs, including the Dodge Durango (rated at 12 mpg in the city and 15 mpg on the highway).

With minor changes and expense, DaimlerChrylser can make the Dodge Durango compatible for E85 fuel. As a result, the E85 Durango can be rated for 23 mpg-instead of the 13 mpg rating for the conventional Durango -even if its owners never use E85 fuel.

Automakers' tendency to make their largest vehicles E85 compatible is rooted in America's fuel economy rules. Since 1988, automakers have been allowed to assign flexible-fuel vehicles higher fuel economy ratings under the government's CAFE fuel economy regulations. This means that a vehicle like the Durango, which averages 13 mpg would be rated at roughly 23 mpg for CAFE purposes, even if its owner never fueled it with E85.

In fact, very few flex-fuel vehicles are using E85, largely because it's not widely available. The DOE lists more than 600 E85 stations in the United States, but nearly half of those are in two states: Minnesota and Illinois. Other areas, even populous ones, have little E85 infrastructure. For example, New York, California, Texas and Florida have just 15 E85 stations combined, only two of which allow sales to the general public.

Ethanol and Biodiesel in the United States

Ford Focus bio-ethanol

 

In his 2007 State of the Union address, President Bush again focused on ethanol as a key renewable fuel that could help displace large volumes of gasoline. This followed his address a year earlier when he made a commitment “to replace more than 75 percent of our oil imports from the Middle East by 2025.” Further, the President said that, “We will also fund additional research in cutting-edge methods of producing ethanol, not just from corn, but from wood chips and stalks or switch grass.” According to the leader of the free world, the goal is no less than to make this new kind of ethanol practical and competitive within six years.

Unlike fuel cells, which still require major investments and technology breakthroughs before they’re practical and affordable, widespread use of biofuels like ethanol and biodiesel basically require investments in the production, transmission, and distribution infrastructure. Indeed, many Americans already own vehicles that can run on ethanol, and may not realize it. Since the late 1990s, Ford, GM, DaimlerChrysler and other automakers have sold millions of flexible-fuel vehicles (FFVs). These vehicles are built to operate on E85, unleaded gasoline, or any combination of the two fuels in the same tank. Thirty 2007 model year vehicles are available in many states that are capable of running on E85.

E85 is a blend of 85-percent ethanol and 15-percent unleaded gasoline. E85 should not be confused with gasohol, which uses a nominal 10 percent ethanol and 90 percent gasoline. Gasohol, or E10, is considered a cleaner-burning gasoline fuel, but not an alternative fuel like E85. In E85, pure ethanol (E100) makes up most of the fuel with gasoline blended in to improve cold starting and as a safety measure. Pure ethanol, really ethyl alcohol, burns with a colorless flame and thus presents a safety hazard without the addition of this small percentage of gasoline.

E85 Chevy Impala

Ethanol Production And Use

Ethanol is now produced by a fermentation and distillation process that converts plant starch to sugar, and then to alcohol. In the U.S., ethanol is basically grain alcohol, produced from corn. It can be made from many other crops such as sugar cane, sugar beets, wheat, barley and vegetable wastes as well. Cellulosic ethanol, as mentioned by President Bush, is made from wood chips, switchgrass, and other natural feedstocks. Eventually, cellulosic ethanol could be produced at much lower cost than corn-derived ethanol.

Production of traditional ethanol is a very mature technology. Henry Ford was an advocate of home-grown renewable fuels and the Model T could be modified to run on pure alcohol. As a mature technology, there’s little that can be done to substantially reduce the cost of corn-based ethanol production. In contrast, there is great potential payoff for investments in research for economically producing cellulosic ethanol in large quantities. Additional feedstocks are needed to meet future large-scale demand since the use of corn and other crops for fuel has to compete with other uses, like food and adult beverages.

Modifying an engine to operate on E85 is pretty simple: add a fuel sensor to detect the ratio of ethanol to gasoline, replace fuel system components that are not compatible with the more corrosive ethanol fuel, and reprogram the engine management computer to account for the varying blend of gasoline and ethanol being burned. This can range from 100 percent gasoline to 100 percent E85, and all mixtures in between. Quantifying the amount of gasoline and E85 being supplied to the engine is easily determined by an oxygen sensor, since E85 contains more oxygen than gasoline.

E85 PumpWhile these modifications are simple, they are required to burn E85. Unlike gasohol, ethanol should not be used in engines other than those designed to operate on this fuel since more corrosive ethanol could damage engine and fuel system components. That said, if a conventional vehicle is accidentally refueled once with E85, damage is not likely. However, the “Check Engine” warning light might come on because of the higher oxygen content measured by on-board sensors.

Ethanol’s Advantages

According to the Alterative Fuel Vehicle Institute, E85 reduces oxides of nitrogen, carbon monoxide, and carbon dioxide emissions. The higher hydrocarbon emissions can be handled relatively easily by exhaust emission control systems. Ethanol advocates point out that E85 CO2 emissions are offset by the CO2 used by crops grown to produce the fuel. Ethanol is now the oxygenate used in reformulated gasoline (RFG) to reduce smog-forming and toxic pollutants now that petroleum-based MTBE (methyl tertiary butyl ether) has been phased out. Once the oxygenate of choice, MTBE has been banned for RFG use since it has been detected in groundwater across the country, the result of reformulated gasoline that’s leaked from underground storage tanks. At best, low levels of MTBE can make water undrinkable due to its offensive taste and odor. Studies are underway to determine its harm to humans.

Unlike gasoline, ethanol fuel can be produced from domestic feedstocks, rather than imported oil. Thus, while the benefits of using E85 might be small on a per-vehicle basis, if used in millions of vehicles the results could be rather dramatic in reducing our dependence on imported oil and improving balance-of-trade. For example, in 2004 ethanol usage reduced the U.S. trade deficit by $5.1 billion by eliminating the need to import 143 million barrels of oil.

FFVs could be the answer to fuel shortages and large spikes in pump prices. Rather than releasing petroleum from the nation’s Strategic Petroleum Reserve, more ethanol could be produced if adequate production facilities were in place and feedstocks immediately available. That’s another reason to pursue cellulosic ethanol, by the way. Also, gasoline producers would now have serious competition, which would make price gouging less likely. Finally, many people would likely pay more for an ethanol-capable FFV as a hedge should gasoline become unavailable or much too expensive.

Driving E85

Most drivers will not notice a difference when driving on E85 or gasoline. The specifications for FFVs compared to conventional gasoline vehicles indicate no difference in torque or horsepower ratings. In reality, FFVs may see a performance improvement since ethanol has a higher octane rating (100 to 105) than gasoline. However, since ethanol produces less energy than gasoline, there could be up to a 25 percent decrease in fuel economy, depending on operating conditions.

Today, the biggest challenge in using E85 is finding places to fill up with the alternative fuel. As of this writing, there are just over 1,000 E85 stations in the entire U.S., most of them in Midwestern corn producing states. Prices for E85 can range from slightly less than gasoline to much more, depending on where you live. This underscores the importance of developing less expensive cellulosic ethanol production technology as a long-term remedy to these price differences.

Currently, E85 is often more expensive because of the added cost to blend ethanol with gasoline, as well as the additional cost involved in shipping ethanol to areas where corn is not grown. Ethanol cannot be transported readily through existing petroleum pipelines and thus must now be transported by barge, rail, or truck. For this and other reasons, petroleum refiners have shown little interest in selling this competitor to gasoline.

Because of today’s generally higher price of ethanol and its lower fuel economy, going “green” with E85 can cost most motorists more. Adding to the cost equation is that E85 now has to compete with reformulated gasoline as a market for available ethanol.

The use of ethanol is a hot political football so its true economic benefits, or penalties, are clouded by subsidies, incentives, and tax benefits. For example, the 1988 Alternative Motor Fuels Act provided incentives for automakers to produce alternative fuel vehicles, but no companion incentive for developing a fueling infrastructure. The result is that there are now about six million E85-compatible vehicles in America, with a very small percentage that have ever had E85 in their tanks.

The Energy Policy Act of 2005 should result in much more renewable ethanol and biodiesel fuels. Plus, the Renewable Fuel Standard Program (RFSP) requires the ethanol industry to raise its production to 4 billion gallons in 2006, gradually rising to 7.5 billion gallons in 2012.

Minnesota, a corn producing state, is leading the way in mandating the use of ethanol. Its goal is to have 20 percent of the liquid fuel sold in the state derived from renewable sources by the end of 2015. Of course, the ethanol lobby played a large role in getting this legislation, which will ultimately benefit the entire nation by displacing imported oil with domestically produced fuel. This could be replicated in other states given the influence of the ethanol lobby, especially in the farm states of the Midwest. For example, the Illinois Clean Energy Infrastructure Program has increased the number of E85 stations in Illinois from 14 to over 100.

The Brazilian Experience

When it comes to ethanol and flexible-fuel vehicles, Brazil is way ahead of the U.S., and indeed the rest of the world. As the fuel crises of the 1970s hit Brazil, the government reacted with Proálcool produced from sugar cane, a major product of Brazil, to reduce dependence on imported oil. In the early 1970s, up to 25 percent alcohol was blended with gasoline. Brazil responded to the second crisis with vehicles that could run on 100 percent alcohol. By 1984, over 90 percent of Brazilian cars and light trucks ran on alcohol, in part because the fuel was available everywhere in Brazil and also because subsidies and incentives made ethanol substantially cheaper than gasoline. However, when oil prices dropped in the mid-1980s and new offshore oil fields were discovered, gasoline became cheaper than the still-subsidized alcohol fuels. This was further compounded by a drought and a poor sugar harvest that disrupted the supply of alcohol. The result? Alcohol capable cars represented less than one percent of new vehicles in 1997.

Brazil learned a lesson from these ups and downs and has since turned to flexible-fuel vehicles that can run on any fuel from pure gasoline to pure alcohol. In reality, all Brazilian gasoline is blended with at least 24 to 25 percent ethanol. Almost all fueling stations in Brazil – 29,000 out of 31,000 – also offer 100 percent ethanol for older alcohol-only vehicles still on the road. Brazil currently has between 3 and 4 million ethanol fueled vehicles. Alcohol costs on average about half that of gasoline, plus motorists receive a tax credit on alcohol cars because of cleaner tailpipe emissions. The bottom line is that Brazil is almost immune to the instabilities, and price fluctuations, in gasoline supplies. Today, Brazilian motorists can fill their tanks with any blend of gasoline or ethanol they choose, depending on which is cheaper, or more convenient.

A new wrinkle has been added to the Brazilian flex-fuel story because vehicles that also run on compressed natural gas are also available. These cars run on any combination of alcohol, gasoline, and CNG. Now, these are primarily aimed at taxi fleets with their own CNG facilities, though CNG is available at some public fueling stations. Besides the substantial savings from using CNG, they may also help reduce pollution in major cities.

Automakers Ramp Up

Automakers in this country are now becoming more engaged in the process after years of just focusing on their flexible-fuel vehicles. For instance, Ford and VeraSun Energy, a renewable energy company, have launched the “Midwest Ethanol Corridor” by expanding E85 availability by about a third throughout Illinois and Missouri this year. This same effort is planning to increase the availability of ethanol in neighboring states.

Ford has also shown a developmental E85 variant of the Escape Hybrid that can run on battery power, gasoline, or a blend of E85. According to Ford, if just five percent of U.S. vehicles were powered by E85 hybrids, oil imports could be reduced by about 140 million barrels a year. According to VeraSun, the two greatest challenges facing greater E85 use are access to convenient fueling locations and a lack of consumer awareness, both of which are being addressed by its partnership with Ford.

General Motors has also tackled the awareness problem with its high-profile “Live Green, Go Yellow” national campaign. This includes equipping all of its FFVs with yellow gasoline caps and fielding a high-profile E85 Chevrolet Silverado in the NASCAR Truck Series. GM has also been offering an E85 Chevy Police Tahoe with a full police package for first-line patrol duty.

There is some controversy about the benefits of using ethanol as a transportation fuel. Critics say it actually takes more energy to produce ethanol than the petroleum-derived energy it saves when accounted on a “field-to-wheel” basis. However, according to the Department of Energy’s Argonne National Laboratory, if 100 BTUs of energy are used to plant corn, harvest the crop, transport it, and so on, 138 BTUs of energy are available in the fuel ethanol produced – a 38 percent increase in energy availability. Future improvements in crop yields and processing technologies, and especially cellulosic ethanol, could increase this percentage substantially. Incidentally, it also takes energy to produce gasoline - about 20 percent of the total energy available.

In all probability, it will be many years before there is enough cellulosic ethanol to meet the President’s target...some experts say 10 to 20 years, about the time fuel cells will be coming into their own. Others point to the growing momentum and investment being enjoyed by ethanol and expect that timeline to be considerably shorter.

In the meantime, ethanol vehicles have every potential to become an important part of the country’s transportation mix. They can contribute to the goal of reducing petroleum use alongside other approaches like hybrids and maybe even hydrogen internal combustion engines, and fuel-saving technologies applied to conventional vehicles as well.