The World Resources Institute, a highly respected environmental think tank issued a new report this week arguing against the widespread use of biofuels. While acknowledging that waste biomass, such as food waste or urban tree trimmings can be efficiently harvested for fuel, the overall quantities would be relatively limited. Biomass crops on the other hand are extremely inefficient for producing energy products such as ethanol or biodiesel.

The real problem with biomass energy crops is that they take land away from other uses such as growing food, sequestering carbon, or providing wildlife habitat. Land is a limited resource with competing uses, and land that is dedicated to one task can not be used for other purposes that may be more beneficial to society and the environment. As populations grow this competition for land use is increasing.

“A new WRI paper finds bioenergy can play a modest role using wastes and other niche fuelstocks, but recommends against dedicating land to produce bioenergy. The lesson: do not grow food or grass crops for ethanol or diesel or cut down trees for electricity.” – World Resources International Blog

The report estimates that providing just 10% of global transportation fuels would require roughly 30% of the total energy in all the crops harvested today.

The report also argues that the carbon benefits of bioenergy have been highly overstated. Bioenergy is not carbon free or carbon neutral despite often repeated claims because carbon is released when the fuels are burned and while the carbon is absorbed when the plants grow, those plants would have been growing anyway and used for some other purpose.

In the end, bioenergy crops only serve to take food off the table and move it to the gas tanks with little or no environmental benefit to show for the effort.