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Using bugs to gin up ethanol
AP
2/18/2006
The key to kicking what President George W. Bush calls America's oil addiction could very well lie in termite guts, canvas-eating jungle bugs and other microbes genetically engineered to spew enzymes that turn waste into fuel.
It may seem hard to believe that microscopic bugs usually viewed as destructive pests can be so productive. But scientists and several companies are working with the creatures to convert wood, corn stalks and other plant waste into sugars that are easily brewed into ethanol - essentially 199-proof moonshine that can be used to power automobiles.
Thanks to biotechnology breakthroughs, supporters of alternative energy sources say that after decades of unfulfilled promise and billions in government corn subsidies, energy companies may be able to produce ethanol easily and inexpensively.
"The process is like making grain alcohol, or brewing beer, but on a much bigger scale," said Nathanael Greene, an analyst with the environmental nonprofit Natural Resources Defense Council.
"The technologies are out there to do this, but we need to convince the public this is real and not just a science project."
Using microbes may even solve a growing dilemma over the current ethanol manufacturing process, which relies almost exclusively on corn kernels and yielded only 4 billion gallons of ethanol last year (compared to the 140 billion gallons of gasoline used in the U.S.). There's growing concern throughout the Midwestern corn belt that the 95 U.S. ethanol plants are increasingly poaching corn meant for the dinner table or livestock feed.
The idea mentioned by Bush during his State of the Union speech - called "cellulosic ethanol" - skirts that problem because it makes fuel from farm waste such as straw, corn stalks and other inedible agricultural leftovers. Cellulose is the woody stuff found in branches and stems that makes plants hard.
Breaking cellulose into sugar to spin straw into ethanol has been studied for at least 50 years. But the technological hurdles and costs have been so daunting that most ethanol producers have relied on heavy government subsidies to squeeze fuel from corn.
Researchers are now exploring various ways to exploit microbes, the one-cell creatures that serve as the first link of life's food chain. One company uses the microbe itself to make ethanol. Others are taking the genes that make the waste-to-fuel enzymes and splicing them into common bacteria. What's more, a new breed of "synthetic biologists" are trying to produce the necessary enzymes by creating entirely new life forms through DNA.
Bush's endorsement of the waste-to-energy technology has renewed interest in actually supplanting fossil fuels as a dominant energy source - a goal long dismissed as pipe dream.
"We have been at this for 25 years and we had hoped to be in commercial production by now," said Jeff Passmore, an executive vice president at ethanol-maker Iogen Inc. "What the president has done is - perhaps - put some wind in the sails."
Ottawa-based Iogen is already producing ethanol by exploiting the destructive nature of the fungus Trichoderma reesei, which caused the "jungle rot" of tents and uniforms in the Pacific theater during World War II.
Through a genetic modification known as directed evolution, Iogen has souped up fungus microbes so they spew copious amounts of digestive enzymes to break down straw into sugars. From there, a simple fermentation - which brewers have been doing for centuries - turns sugar into alcohol.
Iogen opened a small, $40 million (euro33 million) factory in 2004 to show it can produce cellulosic ethanol in commercial quantities. In the last two years, it has produced 65,000 gallons (247,000 liters) of ethanol that is blended with 85 percent gasoline to fuel about three dozen company and Canadian government vehicles. Oil giant Royal Dutch Shell PLC has invested $40 million (euro33 million) for a 30 percent ownership stake in Iogen; Petro-Canada and the Canadian government are also investors.
Now the company is ready to build a $350 million (euro292 million), commercial-scale factory in Canada or Idaho Falls, Idaho, next year if it can secure financing - long one of the biggest stumbling blocks to bringing the stuff to gas pumps.
While conventional lenders are wary of investing in a new technology, the company is banking on winning a loan from the U.S. Department of Energy. Even under a best-case scenario, Passmore said Iogen won't be producing commercial quantities until 2009.
Other significant hurdles include how to widely distribute the fuel; getting auto manufacturers to make engines that will use it; and persuading gas stations to install ethanol pumps. There's hope that funding shortfalls and the remaining technological problems such as how to ship large amounts of ethanol will be overcome in the next few years.
Despite the challenges, Bush's endorsement and advancements in the field have re-energized alternative energy types.
While no commercial interest has advanced as far as Iogen, other biotech companies are engineering bacteria to spit out similar sugar-converting enzymes, and academics are pursuing more far-out sources.
At the California Institute of Technology, Jared Leadbetter is mining the guts of termites for possible tools to turn wood chips into ethanol. Leadbetter said there are some 200 microbes that live in termite bellies that help the household pest convert wood to energy.
Those microbes or their genetic material can be used to produce ethanol-making enzymes. So scientists at the Energy Department's Joint Genome Institute in Walnut Creek, California, are now sequencing the microbe genes in hopes of finding a key to ethanol production.
"We have this idea that microbes are pests," said Leadbetter, who has been studying termite guts for 15 years. "But most microbes are beneficial."
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