I’ve been a little quiet on the blog lately, and maybe one of the reasons was a manuscript that I’ve been working on and would like to highlight here. Since one of my co-authors on the paper is fellow blogger John Field, he will post some perspective from his side of things on the same paper a bit later.
We decided to review the existing knowledge about how to optimize plant biomass for thermochemical bioenergy (basically this means burning the biomass). Since my research is trying to understand how plant genetics can be used to create better bioenergy feedstocks, I’ve thought and written about this before. However, when I talk to alot of the engineers and people thinking of the processing aspect, they don’t seem to think there are major differences in different plants – they generally think of biomass as “woody” or not woody.
We know from a long and successful history of domestication of various plants, we can drastically change the genetics and thus everything about the plant. Just look at the ancestors of modern wheat, corn, or any other food crop. It seemed like there have been lots of papers on the technical aspects of thermochemical conversion, but not many had asked this question: If we wanted to breed (or create with biotechnology) the perfect plant for thermochemical energy … what traits would we target, and how would we measure them? We tend to focus on traits that we know some of the genes that control them, such as the enzymes that make cellulose, but what genes control more abstract traits like “grindability”? Is grindability something that we can explain by the amounts of cellulose and lignin (or alternatively, C, H, and O?)? Is this something we can easily measure – if we can’t measure it easily (and cheaply), we can’t study it.
As we said in the conclusion: “The most biologically interesting traits may not be the traits that will have the greatest economic and lifecycle impact.” In fact, what we find is that the best approach might be to ignore all the cell wall analysis that people work on for enzymatic bioenergy, and just measure the carbon, hydrogen, and oxygen in the biomass, and calculate energy yields and other components from these numbers.
Of course our first submission was not accepted, but they invited us to resubmit so we got to work on reorganizing and trying to make clear what we wanted to say. In the end I think we put together a really nice figure of how certain plant properties relate to eachother, and to bioenergy:
Check out the paper for more:
Paul Tanger, John L. Field, Courtney E. Jahn, Morgan W. DeFoort, & Jan E. Leach (2013). Biomass for thermochemical conversion: targets and challenges Frontiers in Plant Science, 4 (218) DOI: 10.3389/fpls.2013.00218