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The so-called solution to our eco-woes is quickly proving nearly as troublesome as the issue itself

Bioplastics, like biofuels, are on the rise as consumers demand alternatives to fossil fuel-based plastics and big business take their wants seriously. Everything from shopping bags to clamshell containers are being reengineered out of bio-based packaging in the hope of finding a truly disposable container; one that, instead of ending up floating in the ocean, will quickly decompose underground. That ideal, as you might expect, is not quite so simple. And already, our two leading alternative bag types are falling short of the hype.

Packaging made from polyactic acid (something we reported on a few weeks ago) needs anaerobic conditions in order to break down. (This is part of the reason researchers are looking for hybrids of polyactic acid that can break down in all conditions.) Current commercial anaerobic digesters—used mostly for treating wastewater— don’t take this kind of packaging and are very difficult and expensive to maintain. If the bags end up in current plastics recycling operations, they can contaminate the works and make the entire batch they’re in unrecyclable.

The other alternative, oxy-degradable bags and materials, need composters in order to break down correctly. While digesters are as complicated as power plants, a composter can be nothing more than a tremendous pile of hot dirt and waste. Unfortunately, a landfill is not a composter, and that’s where the majority of these bags will end up. Landfills are in fact terrible places for degradation; they’re oxygen-starved and tightly packed, both factors that work against natural chemical breakdown.

If nothing else, these difficulties should tell us we need to think more seriously about not throwing out that shopping bag or even taking it in the first place. No matter how well-engineered it may be to break down in the environment, we are quickly learning the cost of putting it there in the first place.

A maverick group of engineers and scientists at the University of North Dakota’s Energy & Environmental Research Center looks beyond corn and other food crops for biofuel production

Today’s New York Times has a front-page story about how biofuels are driving up food prices around the world and how they therefore may not be a such a great idea after all. That could be true if the only feedstocks available for producing biofuels were food crops, as the article implies, but that’s far from the truth.

Yesterday I visited the Energy and Environmental Research Center, or EERC, at the University of North Dakota in Grand Forks and got a distinctly different side of the biofuels story. “We’re going to have to move away from using food to produce energy,â€� EERC director Gerald Groenewold told me simply. He sees no contradiction with doing that and continuing to ramp up biofuel production. He favors a portfolio approach, with our energy coming from many different sources.

Last December, working under a DARPA contract, the EERC successfully tested military grade jet fuel, called JP-8, made from 100% pure vegetable oil. The DARPA program manager in charge of the project, Douglas Kirkpatrick, tells me the stuff is chemically identical to the petroleum variety and can be used unmodified in jet engines. Next step is to optimize the conversion process for large-scale production, and we’ll be off and running toward independence from petroleum. And, no, the veggie oil doesn’t have to come from corn, soy, or other food crops. It can just as easily come from switchgrass or even algae.

Among the EERC’s many other projects is an electric generator that runs off any kind of organic matter you can feed it in quantity. The slow burn of the fuel inside the processor produces gas, and it’s the gas that runs the generator. A prototype running at a North Dakota truss plant powers the whole facility on scrap wood.

Also under development is an on-demand hydrogen producer that will use biofuels as feedstock. You’ll pull your hydro-powered car up to the pump, and when you stick the nozzle in, the system will generate hydrogen fast enough to fill your tank.

This will eliminate the need for a large-scale hydrogen production and distribution infrastructure, and with biofuel as feedstock, it will also cut the CO2 output from conventional hydrogen production from natural gas.

EERC has a contract with the Army Corps of Engineers’ research lab to develop a portable unit suitable for running on the back of a humvee for generating the hydrogen for fuel cell batteries.

And until we move completely away from fossil fuels, the EERC is working on carbon sequestration projects, devising ways to efficiently pipe CO2 away from power plants and pump it back into the ground before it can escape into the atmosphere and contribute to global warming.

With debate raging on whether biofuels are robbing the world’s hungry of food, scientists and engineers at the first annual BioMass conference in Minneapolis say it ain’t so

The first annual BioMass conference, attended by biofuels researchers, manufacturers, equipment suppliers, and farmers, is underway here at the Minneapolis Convention Center.

Prime on the agenda in the opening session this morning was a question lately blaring from headlines, for instance in a story in today’s New York Times: can we grow crops for converting into fuel without catastrophically upsetting the world’s food supply?

The answer is an unqualified “Yes,” says David Tilman, ecology professor at the University of Minnesota and one of this morning’s speakers. He deplored the polarization of the biofuels debate, pointing out that that biofuels were first touted as a savior a couple of years ago, with public opinion shading into doubt not long afterwards, and now in full-swing backlash mode, with people like the United Nations special rapporteur for the right to food, Jean Ziegler, calling biofuels “a crime against humanity” because it takes food out of the mouths of the hungry according to today’s Times.

What’s needed instead, says Tillman, is a rational look at the big picture, backed by good science. Yes, he acknowledges, the demand for biofuels derived from traditional food crops like corn has contributed to a rise in global food prices, but so has increasing demand for food from burgeoning populations in China and India.

More to the point, though, is the mistaken notion that we have to use food crops for fuel production. In test fields in Minnesota, Tilman and his colleagues have found that the best energy yields actually come from native prairie grasses, not corn or soy. And, said Tilman, “there’s a surprising benefit from the mixture of species. Farmers know this from growing pastures. Nobody plants a pasture of a single species. They put out a variety of grasses, legumes…and so on. They do that because that gives them a higher yield.”

What’s that mean for energy? “We see here we get 238 percent more energy per acre of land that we can harvest mowing this hay in the autumn by growing a high diversity mixture of species than we can get on average by growing any one of those species by itself.”

Tilman’s test plots were “on land that is incredibly unproductive, with very infertile soils… We did not fertilize it, we didn’t water. We put out high diversity native prairie, let them grow….” And energy production from the harvest went through the roof. “Another thing which happened which really surprised us is that we have a lot of carbon being stored in those soils.”

So, growing inedible biofuel crops on otherwise unproductive farmland not only will ease the current pressure on food crops exerted by biofuels, but will also help remove harmful CO2 from the atmosphere. Seems like a win-win.