Cellulosic ethanol, which was supposed to supplant that made from corn in meeting the mandate, has proven a monumental disappointment , and the EPA has taken a big step back from requiring its use. The ethanol industry and others are proposing raising the blend level to 30 percent.
Without such a break in the blend wall, the renewable fuel standards mandates are in trouble. At present, though, fewer than 2 percent of filling stations in the U. Shrouded in the political fumes and corrosive influence of special interests, the economic fundamentals of ethanol are clear in the light of day. Two prices determine its profitability: the price of corn and the price of oil. The higher the price of corn, the more expensive it is to divert from feeding animals or making high-fructose corn syrup and instead distill it as alcohol fuel for cars and trucks.
Second, the higher the price of oil, the more economically ethanol can be blended with gasoline. When corn is cheap and oil prices are high, ethanol margins are fat. But when corn prices rise and oil prices fall, ethanol margins are flat. As ethanol production took off in the mids, aided and abetted by a panoply of federal and state subsidies, it chewed up so much corn so fast that it was hoisted on its own petard as corn prices rose to record highs in while oil prices weakened.
Corn prices then fell back as farmers responded to high prices with record plantings. Today, oil prices remain low and corn prices are strengthening again. Despite recent weakness, corn prices remain nearly double their level of when the major elements of ethanol subsidies and mandates began to be put in place. In the face of these tribulations, the revisionist ethanol narrative makes a number of shaky assumptions.
To date, ethanol has been antithetical to fuel economy. According to the U. Advocates of E30 argue that such inefficiencies can be overcome if high-compression engines are tuned to use the fuel and are certified under EPA rules, making such engines more akin to racecars. If growing corn for ethanol in Iowa meant that farmers had to convert more land into fields, that would completely wipe out the benefit of ethanol.
Researchers are still volleying claims and counterclaims back and forth. By now, Martin told me, "Most life cycle analyses of biofuel incorporate this concept of indirect land use change," and researchers have been refining techniques to capture every bit of greenhouse gas emitted in the fuel production process. That representation suggests that even if we include the impact of indirect land use change, the corn ethanol mixed with our gasoline today has 20 percent less greenhouse gas impact than oil.
But if you take land that was producing, say, hay, and replace it with thick corn in the summer and then winter wheat that same year, you are producing a lot more vegetation, which sucks up a lot more carbon dioxide.
All of that is happening against a background trend of increasing yields as farmers come up with new techniques and better technology. Second, meat production: It sounds crazy to say that people will just eat less as biofuel production claims more land … unless you know that the majority of that land was producing food for animals.
As ethanol production ramped up, it drove up the price of feed, which drove up the price of meat, and — though there may have been other causes as well — Americans cut back on eating animals. Of course, this is happening in different places — the ethanol boom led farmers in the Midwest to plow up a lot of environmentally sensitive land , at the same time that land in the Northeast and South was moving out of agricultural production entirely.
Again, though there has been a tragic amount of forest cut down for agriculture in places like Indonesia and tropical West Africa, other areas are reforesting , and the total amount of cropland worldwide is just about flat. Would farmers in Iowa convert their fields to tallgrass prairie? The industry standard for gasoline is It means more refining of the petroleum, or using high-octane compounds in your gasoline formula, such as — you guessed it — ethanol. You could use methyl-tertiary butyl ether MTBE , but we ditched that in the s because it seemed to be contaminating groundwater.
Finally, you could build more complex refineries to process oil until reaches a higher octane without ethanol. In addition, the Renewable Fuel Standard creates a huge incentive for people to figure out how to mass-produce cellulosic ethanol.
If that happens, farmers really could convert cornfields to tallgrass prairie, then cut the grass and turn it into fuel. So it looks like corn ethanol is much more legitimate than I initially thought, and the measurement of its carbon intensity more complicated.
I should have interviewed more experts and read more up-to-date science before publishing that first piece. The road to knowledge — at least in my case — often winds through the valley of ignorance. I never know exactly where I am along that road, but I do keep walking. Grist is a nonprofit news site that uses humor to shine a light on big green issues. Source: Photo courtesy of Wikimedia Commons public domain. Producing and burning ethanol results in emissions of carbon dioxide CO2 , a greenhouse gas.
However, the combustion of ethanol made from biomass such as corn and sugarcane is considered atmospheric carbon neutral because as the biomass grows, it absorbs CO2, which may offset the CO2 produced when the ethanol is burned. Some ethanol producers burn coal and natural gas for heat sources in the fermentation process to make fuel ethanol, while some burn corn stocks or sugar cane stocks.
The effect that increased ethanol use has on net CO2 emissions depends on how ethanol is made and whether or not indirect impacts on land use are included in the calculations. Growing plants for fuel is a controversial topic because some people believe the land, fertilizers, and energy used to grow biofuel crops should be used to grow food crops instead. The U. Cellulosic ethanol feedstock includes native prairie grasses, fast-growing trees, sawdust, and even waste paper.
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