WASTE NOT, WANT NOT: By fermenting the cellulose in unrecycled paper or lawn clippings, enough ethanol to offset one third of U.S. fuel consumption can be made.
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The remains of plants processed for human purposes molder in landfills across the world. Whether waste paper or raked leaves, the plant remnants still contain cellulose, a sugar in greenery that bonds with the chemical compound lignin to furnish a plant's structure. Microbes living in the landfills break down this cellulose into methane, which slowly seeps to the surface and into the atmosphere, where it is a potent greenhouse gas. BlueFire Ethanol, Inc., in Irvine, Calif., would rather harvest that energy for use as cellulosic ethanol fuel.
"We produce 70 gallons of ethanol per ton of waste," says engineer Arnold Klann, BlueFire's president and CEO. "The trick is unlocking the sugar molecule from the lignin, which is the glue that holds it together."
BlueFire estimates 40 billion gallons of cellulosic ethanol could be produced from plant waste destined for the landfill, providing as much as one third of all U.S. transportation fuel needs. And, if other forms of waste, such as the stalks of corn plants (corn stover) or the remnants of timber harvest are included, Klann says, "we have enough feedstock in the U.S. to offset 70 percent of the oil import."
BlueFire is set to open its first plant at a landfill in Lancaster, Calif., later this year and hopes to use U.S. Department of Energy (DOE) funding to open a second by the end of 2008, Klann says. Together the two plants would produce, at best, 22 million gallons of ethanol a year by using sulfuric acid to break the lignocellulose bonds and then burning the leftover lignin to power fermentation of the cellulose into ethanol. "The lignin we recover makes up 70 percent of the steam and electricity we need," Klann notes. "The other advantage of siting at a landfill is that they have methane gas. We can burn that in our boiler and generate huge carbon credits."
Given the potential benefits, Congress has provided $10 million in funding—and the DOE has asked for $30 million more—to develop a second facility employing the process, as well as millions more for similar cellulosic biorefineries, such as the Range Fuels plant in Soperton, Ga., that converts wood waste into fuel.
Biofuels from waste avoid the carbon and energy debts incurred by more common examples such as ethanol from corn or diesel from soy. "The thing we know will work is if you use waste products," says agricultural expert Tim Searchinger of Princeton University, who led recent research showing that most biofuels do little to slow and may even increase global warming. "If everything is done right, probably we can use corn stover without other problems, though it might mean you have to grow a cover crop."
Biofuels also offer one of the few methods currently available for storing solar energy, notes chemical engineer Charles Wyman of the University of California, Riverside. "Biomass to liquid fuel, electricity for charging of a battery or generating hydrogen, [those are] really our options," he says. "The best way to store solar energy is called biomass."
BlueFire has already operated such a plant to convert wood waste into ethanol in Japan to demonstrate the feasibility of the technology. As a result, the government of that country has decided to mandate blending 1 percent of ethanol into gasoline for the first time. And Klann believes this technology could prove most useful in the developing world, where plant waste is typically burned rather than buried. "What we have to do as a society is figure out how to move ourselves around in a way that is low-cost and has minimal effect on the environment," he says. "Ethanol is not a bad fuel."
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7 Comments
Add CommentHow refreshing. Congrats to Charles Wyman. Finally people in the United States have caught on. "The best way to store solar energy is called biomass."
Reply | Report Abuse | Link to thisIn wood products such as paper, wood chips etc. the carbon dioxide is locked. Provided it does not breakdown it will remain permanently locked in the landfill, in the absence of water this must be the case. So if we convert this wood to ethanol and then burn it we are effectively releasing locked CO2 into the atmosphere again. How does this reduce global warming?
Reply | Report Abuse | Link to thisI am sure that there will soon be a report released that this is worse for the environment then continuing to use oil. Of course, it will most likely be funded by the oil companies.
Reply | Report Abuse | Link to thisI.E. all of the "biofuel is going to ruin the planet so just keep using oil" reports in the last week.
My guess is that these reports will go along the lines of using garbage to make fuel will be found to increase the mentality of a throw away society and all of the fuel used by the garbage trucks will do more harm then the benefits of the garbage recycling.
Quietly followed by the disclaimer, "I am Hugo Chavez and I approve this message, you American devils."
Oh so cynical friends but, being the son of an Irish mother, I love sarcasm in all its forms.
Reply | Report Abuse | Link to thisHowever, to answer your question patogreen: the carbon doesn't stay locked in the plant matter. Those pesky microbes--as well as the heat and pH of the landfill itself--tend to break it down, converting it back to carbon dioxide or, even worse, methane (which, while shorter lived in the atmosphere traps roughly 23 times the heat). That's why you see so many folks looking seriously at methane from landfills as a greenhouse gas-friendly fuel source for their industrial needs.
That said, the greenhouse gas benefits are confined to waste, whether that be corn stalks that aren't needed to replace organic carbon in the soil or paper that somehow evaded recycling. Of course, if we stopped using paper entirely and let those trees grow... Well, there are no perfect solutions.
Hope that helps.
It is obvious that some biomass in waste gets converted to CO2 or Methane, but what %? Whereas this process will convert 100% back to C02. We can't keep looking for ways for greedy consumers to drive oversized vehicles helping to destroy the planet for convenience and ego's sake. Try using a bicycle or scooter? Still I guess waste is a better source of biofuel than corn which amounts to starving someone so that a lazy fat person can conveniently get from A to B.
Reply | Report Abuse | Link to thisit's has review many sites like gas for free,run your car on water etc.
Reply | Report Abuse | Link to thisYou can truly get better mileage...... http://carwaterguide.blogspot.com
Better to use corn stalks and leaves, rather than the cobs. Nature has been recycling biomass for millions of years, releasing methane and CO2 in the process. Burning wood or biomass does not add to atmospheric CO2. It is only fossil fuels(oil, gas and coal)which add to the CO2 which was locked away in times past.
Reply | Report Abuse | Link to thisLets face facts: Look into the past climate records: See the peaks and troughs of global temperature change.We have always had climate change, for ever.
Have you heard this typical statement: The warmest summer/winter since 1934...or whenever. Do you remember in the 1970s they thought we were heading for another ice-age? This whole thing is just an excuse for people to make vast sums of money(Al Gore springs to mind)Let's jump on the bandwagon! Make hay while the sun shines!