House Science Committee Hearing on the RFS, November 3, 2015 (photo credit: Michael A. Waring) |
Following the recent hearing on the Renewable Fuel Standard (RFS)
held by the House Science Committee, the subcommittee chairs asked me to respond to some questions for the record, following up on my testimony
at the hearing. Here are the questions and an abbreviated version of the answers,
summarizing my full written response.
In his testimony, Mr. Coleman referenced
cellulosic ethanol that is "129 times better than gasoline on carbon
emissions." Based on your research, is this a reasonable claim?
No, that is not a reasonable claim. Such assertions are
based on paper studies of hypothetical ethanol production methods. There is
indeed a literature on the subject that applies lifecycle analysis (LCA) to
proposed cellulosic ethanol production methods and projects that the resulting
systems would not only fully offset tailpipe CO2 emissions but also
offset other CO2 emissions such as those from fossil-based
electricity generation.
However, as pointed out in my testimony (and in papers
explained elsewhere on this blog), the LCA methods used to justify such claims
are scientifically incorrect. Moreover, the cellulosic processing methods
involved remain speculative as far as any meaningful commercial-scale operation
is concerned. In short, claims of biofuels that achieve a more than 100%
reduction in carbon emissions are rooted in flawed analysis of fantasy fuels.