"there are worries that cellulosic conversion technology could have severe environmental consequences.
In an editorial published in the April 10, 2006 issue of Forbes ('The Forest Killers'), Manhattan Institute senior fellow Peter Huber argued that cellulosic ethanol could hasten the conversion of forestlands and other wilderness into a fuel source.
The above figure from the U.S. Department of Energy explains plant cell wall structure (biomass) and some of the issues preventing their efficient conversion to ethanol. Click here for a full size image with explanation.
Earlier this year the DOE announced the goal of making ethanol a practical and cost-competitive alternative by 2012 (at $1.07/gal) and displacing 30% (60 billion gallons) of gasoline by 2030. The United States now produces 4.5 billion gallons of (corn-grain) ethanol per year, a fraction of the 140 billion gallons of transportation fuel used annually.
Huber said that the development of efficient cellulose-splitting enzymes to convert plant structural materials into sugars then alcohols could 'quickly turn a hundred pounds of wood chips or grass into a gallon of diesel.' The origin of this biomass could be farm waste or, in a tropical developing country, it could be freshly cut from a rainforest teeming with biodiversity. "
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