When it comes to biofuels we have choices. We can do it poorly, using short-run approaches with no potential to scale, poor trajectory, and adverse environmental impact. Or we can do it right, with sustainable, long-term solutions that can meet both our biofuel needs and our environmental needs.
We do need strong regulation to ensure against land-use abuses. I have suggested that each cellulosic facility be individually certified with a LEEDS-like "CLAW" rating, and that countries which allow environmentally sensitive lands to be encroached be disqualified from CLAW-rated fuel markets.
We think a good fuel has to meet the CLAW requirements:
C -- COST below gasoline
L -- low to no additional LAND use; benefits for using degraded land to restore biodiversity and organic material
A -- AIR quality improvements, i.e. low carbon emissions
W -- limited WATER use.
Cellulosic ethanol (and cellulosic biofuels at large) can meet these requirements.
Environmentally, cellulosic ethanol can reduce emissions on a per-mile driven basis by 75-85% with limited water usage for process and feedstock, as illustrated later. Range, Coskata, and others currently have small-scale pilots projecting 75% less water use than corn ethanol, with energy in/out ratio between 7-10 EROI (though we consider this a less important variable than carbon emissions per mile driven).
Sustainable land use
The question about biomass production that arises first is about land use: how much will we need? What will it take? Is it scalable? For conservatism, I assume CAFE standards in the U.S. per current law, though I expect by 2030 to have much higher CAFE and fleet standards (hopefully up near 54mpg or a 100% higher that 2007 averages), which will dramatically reduce the need for fuel an hence biomass. Yes, this would include lighter vehicles, more efficient engines, better aerodynamics, low-cost hybrids, and whatever else we can get the consumer to buy that increases mpg.