Post by Icarus on Apr 4, 2008 17:03:23 GMT -5
Recently you’ve probably heard some buzz about ethanol — through advertisements, magazine articles, news reports, etc. You may have even seen ethanol at your local gas station. But step back from the positive impressions you may have because despite the hype, ethanol isn’t an easy solution to our oil addiction. In fact, there are many nuanced and complicated issues around this biofuel. Whether it’s the current or future forms of ethanol, there are pros and cons, promises and perils.
What is ethanol?
Ethanol is ethyl alcohol, sometimes also called “grain alcohol.” In the United States, most ethanol fuel is produced from corn. In a nutshell, ethanol is made by fermenting the sugar and starch in the corn into alcohol, which is then separated from the water by distillation.
You’re far more likely to encounter ethanol as a gasoline additive rather than a full-fledged fuel. E10 (10 percent ethanol, 90 percent gasoline) can be used in any gas engine and is much more widely available than E85 (85 percent ethanol, 15 percent gasoline), which can only be used in “ flex-fuel” cars and trucks.
So what’s wrong with ethanol?
The first and foremost problem with today’s ethanol is it comes from corn, one of the most prominent food crops worldwide. Growing a crop for both food and fuel is problematic because the increased demand for the food crop leads to higher food prices. This, among other factors, has caused worldwide corn and grain production to struggle to keep up and prices have risen to record levels.
Lester Brown, president of the Earth Policy Institute, describes this as the beginning of a great tragedy. “The United States, in a misguided effort to reduce its oil insecurity by converting grain into fuel for cars, is generating global food insecurity on a scale never seen before,” he writes.
But that’s not all that pops the argument for corn-derived ethanol:
E85 leads to about 30 percent less fuel economy than gasoline.
E85 typically costs less than gasoline (As of this article, the average cost of ethanol was $2.80 a gallon compared to $3.20 a gallon for gasoline.), but only because of the support of federal subsidies (funded by our taxes).
Its availability is dramatically limited compared to gasoline. There are only 1,200 stations across the United States that sell ethanol, and they are primarily located in the upper Midwest. In other words, there may be millions of flex-fuel vehicles on the road, but comparatively few actually use ethanol.
Ethanol cannot be transported through existing pipelines because it is corrosive and easily absorbs water. So it must be delivered by trucks, barges and rail cars, producing more pollution.
Switching from gasoline to ethanol may not always save energy. At best, the energy produced by the fuel is only slightly more than the energy required to make it.
Converting prairie, forests and rainforests into cropland destroys carbon dioxide gobbling resources.
Even if all of our corn and soybean production went to ethanol, we could offset just 12 percent of our gasoline consumption. When you look at the numbers, it would be far easier to meet our energy needs with solar-powered electric cars.
Growing corn and producing ethanol could put pressure on local water supplies and increase water pollution.
What About Future Forms of Ethanol?
In order for ethanol to be a realistic option, it will need to be derived more efficiently than ethanol from corn. Promising research is being conducted on cellulosic ethanol, which can be made from sources such as switchgrass and wood chips, which are widely available and aren’t food crops. In fact, a study from the U.S. departments of Energy and Agriculture thinks that two-thirds of our trash contains cellulose that could become fuel. Cellulosic ethanol’s prospective bang for the buck is much greater than that for corn ethanol, with anywhere from twice to 36 times the energy output versus the input, depending on the source and production technique. More research is needed to make the promise of cellulosic ethanol a reality — the biggest challenge is to make it cost competitive with corn ethanol.
Fortunately, recent energy legislation should help encourage the development of cellulosic ethanol.
So what’s the verdict?
Ethanol has a long way to go until it becomes America’s replacement for gasoline. Not yet cost-effective or good for the environment, corn ethanol fails to provide adequate resources without significant downsides.
More research on ethanol may make it a better option in the future, but for now you should think twice before filling your car’s tank with ethanol, because there’s a significant downside to using this fuel. The current emphasis on corn ethanol sets up a risky competition between food for the world’s people and fuel for those who have vehicles. And the current momentum behind its production may do more to exacerbate global warming than stem it. There is reason to be optimistic about cellulosic ethanol, but even with long sought-after technological breakthroughs it’s unlikely to be a wholesale replacement for gasoline. Instead, to maintain our mobility and slow global warming, we’re going to need a combination of strategies: increased efficiency; advanced public transportation; electric and hybrid-electric vehicles; and more. Although all of these solutions have yet to come together, we’re getting there and the answer may be just around the corner.
www.motherearthnews.com/Green-Transportation/Ethanol-Pros-And-Cons.aspx?page=2
What is ethanol?
Ethanol is ethyl alcohol, sometimes also called “grain alcohol.” In the United States, most ethanol fuel is produced from corn. In a nutshell, ethanol is made by fermenting the sugar and starch in the corn into alcohol, which is then separated from the water by distillation.
You’re far more likely to encounter ethanol as a gasoline additive rather than a full-fledged fuel. E10 (10 percent ethanol, 90 percent gasoline) can be used in any gas engine and is much more widely available than E85 (85 percent ethanol, 15 percent gasoline), which can only be used in “ flex-fuel” cars and trucks.
So what’s wrong with ethanol?
The first and foremost problem with today’s ethanol is it comes from corn, one of the most prominent food crops worldwide. Growing a crop for both food and fuel is problematic because the increased demand for the food crop leads to higher food prices. This, among other factors, has caused worldwide corn and grain production to struggle to keep up and prices have risen to record levels.
Lester Brown, president of the Earth Policy Institute, describes this as the beginning of a great tragedy. “The United States, in a misguided effort to reduce its oil insecurity by converting grain into fuel for cars, is generating global food insecurity on a scale never seen before,” he writes.
But that’s not all that pops the argument for corn-derived ethanol:
E85 leads to about 30 percent less fuel economy than gasoline.
E85 typically costs less than gasoline (As of this article, the average cost of ethanol was $2.80 a gallon compared to $3.20 a gallon for gasoline.), but only because of the support of federal subsidies (funded by our taxes).
Its availability is dramatically limited compared to gasoline. There are only 1,200 stations across the United States that sell ethanol, and they are primarily located in the upper Midwest. In other words, there may be millions of flex-fuel vehicles on the road, but comparatively few actually use ethanol.
Ethanol cannot be transported through existing pipelines because it is corrosive and easily absorbs water. So it must be delivered by trucks, barges and rail cars, producing more pollution.
Switching from gasoline to ethanol may not always save energy. At best, the energy produced by the fuel is only slightly more than the energy required to make it.
Converting prairie, forests and rainforests into cropland destroys carbon dioxide gobbling resources.
Even if all of our corn and soybean production went to ethanol, we could offset just 12 percent of our gasoline consumption. When you look at the numbers, it would be far easier to meet our energy needs with solar-powered electric cars.
Growing corn and producing ethanol could put pressure on local water supplies and increase water pollution.
What About Future Forms of Ethanol?
In order for ethanol to be a realistic option, it will need to be derived more efficiently than ethanol from corn. Promising research is being conducted on cellulosic ethanol, which can be made from sources such as switchgrass and wood chips, which are widely available and aren’t food crops. In fact, a study from the U.S. departments of Energy and Agriculture thinks that two-thirds of our trash contains cellulose that could become fuel. Cellulosic ethanol’s prospective bang for the buck is much greater than that for corn ethanol, with anywhere from twice to 36 times the energy output versus the input, depending on the source and production technique. More research is needed to make the promise of cellulosic ethanol a reality — the biggest challenge is to make it cost competitive with corn ethanol.
Fortunately, recent energy legislation should help encourage the development of cellulosic ethanol.
So what’s the verdict?
Ethanol has a long way to go until it becomes America’s replacement for gasoline. Not yet cost-effective or good for the environment, corn ethanol fails to provide adequate resources without significant downsides.
More research on ethanol may make it a better option in the future, but for now you should think twice before filling your car’s tank with ethanol, because there’s a significant downside to using this fuel. The current emphasis on corn ethanol sets up a risky competition between food for the world’s people and fuel for those who have vehicles. And the current momentum behind its production may do more to exacerbate global warming than stem it. There is reason to be optimistic about cellulosic ethanol, but even with long sought-after technological breakthroughs it’s unlikely to be a wholesale replacement for gasoline. Instead, to maintain our mobility and slow global warming, we’re going to need a combination of strategies: increased efficiency; advanced public transportation; electric and hybrid-electric vehicles; and more. Although all of these solutions have yet to come together, we’re getting there and the answer may be just around the corner.
www.motherearthnews.com/Green-Transportation/Ethanol-Pros-And-Cons.aspx?page=2