Crops For Bioenergy

THE ARTICLE "Cellulosic Ethanol Deemed Feasible" observed that "the switchgrass grown as a bioenergy crop produced 540% more renewable energy than the nonrenewable energy needed to produce it and convert it to ethanol" (C&EN, Jan. 21, page 45). This suggests that the point has been reached where nonrenewable (fossil) energy is no longer needed. Rather, it implies that the biofuels themselves provide the required production and processing energy. Doing this would also eliminate the frequent reiteration of a comparison of biofuel energy produced per unit of fossil fuel energy required: The latter would be zero.

Rane L. Curl
Ann Arbor, Mich.