B iofuels are liquid energy Ver- sion 2.0. Unlike their fos- sil fuel counterparts — the cadaverous remains of plants that died hundreds of millions of years ago — biofuels come from vegetation grown in the here and now. So they should offer a carbon-neutral energy source: Plants that become biofuels ideally consume more carbon dioxide during photosynthesis than they emit when processed and burned for power. Biofuels make fossil fuels seem so last century, so quaintly carboniferous. And these new liquid fuels promise more than just carbon correctness. They offer a renewable, home-grown energy source, reducing the need for foreign oil. They present ways to heal an agri- cultural landscape hobbled by intensive fertilizer use. Biofuels could even help
clean waterways, reduce air pollution,
enhance wildlife habitats and increase
biodiversity.
Yet in many respects, biofuels are in
their beta version. For any of a number
of promising feedstocks — the raw materials from which biofuels are made —
there are logistics to be worked out, such
as how to best shred the original material and ship the finished product. There
is also lab work — for example, refining
the processes for busting apart plant cell
walls to release the useful sugars inside.
And there is math. A lot of math.
The only way that biofuels will add up
is if they produce more energy than it
takes to make them. Yet, depending on
the crops and the logistics of production,
some analyses suggest that it may take
more energy to make these fuels than
they will provide. And if growing biofuels
creates the same environmental problems that plague much of large-scale
agriculture, then air and water quality
might not really improve. Prized ecosystems such as rain forests, wetlands
and savannas could be destroyed to grow
crops. Biofuels done badly, scientists say,
could go very, very wrong.
“Business as usual writ larger is not
an environmentally welcome outcome,”
states a biofuels policy paper authored
by more than 20 scientists and published
in Science last October.
Many scientists have expressed concern that political support for the biofuels
industry has outpaced rigorous analyses of the fuels’ potential impacts. Others see this notion as manure. Research
needed to resolve that disagreement is
now underway, as scientists in industry,
national labs and universities across
the country are assessing every aspect
of these fuels, from field to tailpipe.
Researchers are growing crops, evaluating yields and comparing harvesting
techniques. Computer models are providing stats on each crop’s effect on environmental factors such as soil nutrients
and erosion. The plant cell wall is under
attack from several angles. And chemists and microbiologists are cajoling an
S. LONG/UNIV. OF ILLINOIS; USDA-NRCS PLANTS DATABASE
Perennial plants, like this Miscanthus
giganteus in a University of Illinois test
plot, could replace corn as a source of
plant-based liquid fuel.
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