In the first post of this series, I claimed that biofuels are an even more appealing solution for securing our energy future today than they were when they were the darlings of the media and investors in the late 2000s.

Why were we so enamored with cellulosic biofuels’ promises nearly a decade ago? And why has their luster dulled in the wandering eyes of the media, policy makers, and the general public? Today’s blog post addresses a few of the benefits touted by proponents of advanced cellulosic biofuels and their relevance today, particularly focusing on three advantages offered by cellulosic biofuels: renewable, sustainable, and economically competitive.

Renewable Renewable energy is any energy source that can be either replenished continuously or within a moderate timeframe, as a result of natural energy flows.  Biomass can be regenerated constantly; we have only to look at all the green surrounding us to see the vast potential for the planet to grow biomass naturally. If sustainably managed, every acre of a perennial energy crop is like an oil well that never runs dry.  A seminal 2011 study from the US Department of Energy and the US Department of Agriculture estimated that the U.S. could produce more than a billion dry tons of biomass resources annually for energy uses without impacting other vital functions of the farm sector including food, feed, and fiber.
Sustainable Just being renewable is necessary but not sufficient to be an attractive energy source.  Sustainability can be defined as adopting practices and developing products that are environmentally, socially, and economically sound, and that can meet present needs without compromising the ability of future generations to meet their needs.  Sustainably sourced energy accounts for a variety of agricultural, social, ecological and economic relationships including land use, water use, energy efficiency, and biodiversity, among others.  Recently, broad-based efforts involving diverse perspectives and stakeholders have advanced to define sustainability indicators and criteria and to provide a science-based framework for measuring a