Cellulosic Biofuels: Importance, Recalcitrance, and Pretreatment

Abstract

The two most profound societal transformations in history have been spawned by radical shifts in humankind’s use of natural resources. The agricultural revolution, which spanned about two millennia beginning around 4000 BC, saw hunter-gatherer societies subsisting on wild plants and animals being largely displaced by those cultivating the land to produce crops and domesticated livestock. The industrial revolution followed, beginning around 1700 and lasting roughly two hundred years, during which time preindustrial agricultural societies gave way to those harnessing precious metals and fossil energy to develop sophisticated economies centered around machinery and factories. Now, with ever-increasing indications that resource use is exceeding the world’s sustainable capacity, it is clear that a third revolution – the sustainability revolution – must begin soon and must be completed in decades, not centuries [1]. A few centuries hence, we think it is quite likely that people will look at those of us alive today, observe that “It was pretty obvious at the start of the third millennium that humanity needed to rapidly shift from resource capital to resource income,” and evaluate us largely on our success at meeting this defining challenge of our time.