Close to 20 years ago (the story is no longer online, so you’ll have to take my word for it) I wrote about Lee Lynd, a professor at Dartmouth who was one of the leading lights in the push to create cellulosic biofuels – that is, biofuel made from the woody and stemmy parts of plants rather than the parts where Nature had already done the hard job of creating sugars, such as corn kernels. Because there’s a lot more cellulose than sugar in most plants, this remains a very desirable goal for replacing petroleum-based liquid fuels.
Lynd told me that it’s hard to break down cellulose, which has evolved for billions of years to be tough and durable, but he was optimistic that some combination of enzymes or heat and pressure or chemical treatment or all of the above would do the trick, and do it in the not too distant future. I had visions of Northern New England becoming the Saudi Arabia of liquid fuel made from all those trees.
Decades later, as Lynn says in a big piece in Nature Biotechnology, “by any measure, the biofuels landscape today is a pale shadow of what was imagined a decade ago. … The amount of global cellulosic ethanol capacity retired last year exceeded the amount added.” (The article has been reprinted in large part by the Thayer School of Engineering at Dartmouth – read it here).
The obstacles, Lynd writes, were partly economic (the fall in oil prices), partly lack of support for the development of renewables (no cost of carbon), partly the fact that biofuel require growing something and thus run into land use and food concern issues, and partly irrational exuberance of the sort I demonstrated:
Amidst frequent claims that economically viable technology was in hand and investment was needed only in scale-up and commercialization, investment in new, potentially low-cost processing paradigms was generally modest. As a result, technological advancement was slower than it might have been, and policies were designed assuming that deployment, rather than technology, was the limiting factor. The impacts of a tendency to try to vault 100-foot cliffs with 10-foot poles were compounded by the very large size of investments of $250–$500 million and relatively long duration of the design-build-operate-learn cycle in the cellulosic biofuels field. In sharp contrast, other renewable energy technologies proceeded in a stepwise fashion, recognized the need for technological advancement and invested accordingly, and benefited from projects with lower costs and more rapid learning cycles
All is not lost, he says, but it won’t be easy.
With swings from irrational exuberance to dismissal behind us, it is time to see cellulosic biofuels as they are. They remain an important and likely necessary component of climate change mitigation strategies, but face substantial technological challenges to achieve financial viability. They require learning by doing to maximize favorable social and environmental outcomes and to enhance competitiveness with incumbent fossil fuels, which have benefited from a century of investment and development.
So even if we won’t become the Saudi Arabia of fuel from trees, maybe we’ll be part of the climate solution.
(A personal note: When I went to interview Lynd years ago we realized we had gone to the same college – in turns out I had typed his senior thesis in those pre-word-processing days when I used my 80 words-per-minute typewriter skills to make a few bucks.)