Biofuels - The Oxford Topic of Food, Politics, and Society - page 192

of biofuel in 2022.” This mandate would require 1.6 billion tons of biomass harvested per
year as well as harvesting 80% of all biomass in the United States, including all agricul-
tural crops, grasses, and forests (Pimentel et al. 2009). With nearly total biomass har-
vested, biodiversity and food supplies in the United States would be decimated; there is
no evidence either in Perlack et al. (2005) or in the legislation (which is based largely on
Perlack et al.'s assumptions) that this eventuality was ever considered.
Most conversions of biomass into ethanol and biodiesel result in a negative energy
return, based on careful up-to-date analysis of all the fossil energy inputs. Four of the
negative energy returns are as follows: corn ethanol at minus 46%; switchgrass at minus
50%; soybean biodiesel at minus 63%; and rapeseed at minus 58%. Even palm oil produc-
tion in Thailand results in a minus 8% net energy return, when the methanol require-
ment for transesterification is considered in the equation.
Increased biofuel production also has the capability to impact the quality of food
plants in crop systems. The release of large quantities of carbon dioxide associated
with the planting and processing of plant materials for biofuels is reported to reduce
the nutritional quality of major world foods, including wheat, rice, barley, potatoes,
and soybeans (Taub et al. 2008). Carbon dioxide levels are already over 30% higher
than preindustrial levels, and they may double or even triple over the course of the
21st century (Loladze 2002). When crops are grown under twice the ambient atmo-
spheric concentration of carbon dioxide, the mean protein levels in the crops may
be reduced as much as 14%, and other micronutrients, such as phosphorus, sulfur,
iron, calcium, zinc and copper, decline significantly as well (Loladze 2002; Taub
et al. 2008).
There are additional problems associated with biofuels that have been ignored by
some scientists and policymakers. The biofuels being created in order to diminish the
dependence on fossil fuels actually depend on fossil fuels. In most cases, more fossil
energy is required to produce a unit of biofuel compared with the energy that is pro-
duced (Pimentel et al. 2009). Furthermore, the United States is importing oil and natural
gas to produce biofuels, which is further increasing the US dependence on foreign fossil
fuels. Publications promoting biofuels have used incomplete or insufficient data to sup-
port their claims. For instance, claims that cellulosic ethanol provides net energy (Tilman
et al. 2006) have not been experimentally verified because most of their calculations are
theoretical—not a single commercial cellulosic ethanol production plant exists. Finally,
environmental problems including water pollution from fertilizers and pesticides, global
warming, soil erosion, and air pollution are intensifying with biofuel production. There is
simply not enough land, water, and energy to produce biofuels at acceptable cost in terms
of the externalities already apparent. Increased use of biofuels would therefore further
damage the global environment and, especially, the world food system.
Are there alternatives to the current trend of increasing production of biofuels? One
alternative that has not even been suggested in the United States since the Carter admin-
istration is energy conservation. Conservation would probably involve the federal gov-
ernment having a say in how products are produced and how efficiently these products
utilize energy. For example, the Obama administration has worked to set targets for
miles/gallon for vehicles produced by the automotive industry; a more expansive energy