Skip to comments.Study: Miscanthus More Than Twice as Productive as Switchgrass for Energy Crop
Posted on 07/12/2007 8:28:29 AM PDT by Red Badger
Miscanthus. Standing next to the grass is Dr. Emily Heaton (now with Ceres), who is 5' 4" (163 cm) tall. Source: UIUC
Researchers at the University of Illinois at Urbana-Champaign have made the first direct comparisons of the biomass productivity of two C4 perennial grasses: switchgrass (Panicum virgatum) and Miscanthus (Miscanthus x giganteus). The two have been widely trialed as low-input bioenergy crops in the US and EU, respectively.
Results from the trials throughout Illinois show that Miscanthus is more than twice as productive as switchgrass. Its efficiency of conversion of sunlight into biomass is amongst the highest ever recorded. The research team presented their results at Plant Biology and Botany 2007, a joint congress including the American Fern Society (AFS); the American Society of Plant Biologists (ASPB); the American Society of Plant Taxonomists (ASPT); and the Botanical Society of America (BSA).
The team, led by Frank Dohleman of the Plant Biology Department, theorized that Miscanthus produces more usable biomass than switchgrass because of these three key attributes:
Miscanthus can gain greater amounts of photosynthetic carbon per unit of leaf area; 2.
Miscanthus has a greater leaf area; and 3.
Miscanthus has a longer growing season.
The research team measured the amount of gas exchanged on the upper canopy of Miscanthus leaves from pre-dawn to post-dusk on 20 dates in the 2005 and 2006 growing seasons. The averages from two years data showed that Miscanthus gained 33% more carbon than switchgrass.
Integrated measurements also showed that the Miscanthus leaf area was 45% greater than switchgrass and that Miscanthus plants grew an average of eleven days longer than switchgrass. This extended growing season and accompanying lower temperatures proved to further boost the photosynthetic activity of Miscanthus. Specifically, pyruvate Pi dikinase was found to be expressed at higher rates when ambient temperatures are lower. This enzyme supports C4 photosynthesis in Miscanthus.
The University of Illinois at Urbana-Champaign is working with the University of California at Berkeley and the Lawrence Berkeley National Laboratory in forming the new $500-million Energy Biosciences Institute (EBI) funded by BP, with UC Berkeley taking the lead. (Earlier post.)
As part of the EBI, some 340 acres of farmland at the Urbana campus will be devoted to the study and production of feedstock for biofuel production. Researchers will explore the potential benefits of using corn crop residues, switchgrass, Miscanthus and other herbaceous perennials as fuel sources. The initiative will explore how adequate supplies of high quality plant biomass can be sustainably produced and utilized in facilities that convert the biomass to fuels.
Feedstock development is one of five research areas at the EBI. The others are biomass depolymerization; fossil fuel bioprocessing (converting heavy hydrocarbons to cleaner fuels) and carbon sequestration; socio-economic systems; and biofuels production. In addition to feedstock development and socio-economic research, Illinois will work with the other research institutions on biofuels production. UC Berkeley will lead this part of the project, with Illinois joining the search for the most efficient use of microbes to harvest the energy in plants for biofuels.
Resources: Does increased daily carbon assimilation coupled with a higher Leaf Area Index and longer growing season explain the difference in productivity between two potential bioenergy crops?
I just planted this in my yard (got tired of feeding the deer with everything else). Now I have my own “Green Gold!”
That chick is hot.
The grass in my yard is whatever my neighbors half a mile in all directions have seeded their lawns with. There must be twenty varities. They all grow very quickly for a few days and then stop. If there is a way to program grass growth so some is always in this rapid growth phase there could be a never-ending supply of biomass. That stuff is over and done in a week.
If we are going to use biofuels this is the only way that makes sense. Using corn is idiotic.
She can’t be hot. She’s standing in the shade.......
It’s not just growth but the right stuff to turn into ethanol........If it was just growth, kudzu would be perfect........
Not everybody is aware that all corn is engineered and Monsanto is already working on hybrid specials for the ethanol process.
In order to be feasible it would need to generate, at a bare minimum, about 10 times as many gallons of ethanol per acre than corn does.
We don’t have kudzu, but we have vetch. Bumper crop this year. Totally useless but looks nice from a distance of 200 yards.
You don’t have kudzu.....now........but you will eventually......It’s slowly covering the entire planet............
In addition, most people think that we have a realistic way to crack cellulose. Until that problem is solved, all we can do with this grass is burn it or feed it to cows.
If you look carefully, there’s some tall grass growing in the background.
It's not totally useless. It's a legume and fixes nitrogen, so therefore it's good for the soil. It can be made into hay (it ain't alfalfa, but it's got some protein). Also, it makes a seed that ground birds such as quail like to eat.
Kudzu is the goatherder’s friend. Fence it off and turn ‘em loose...they’ll eat it down to the dirt, and continue to chomp every successive shoot that comes up. Kudzu is great fodder, and over time the goats’ll kill it if you’ve got a high enough density of goats on the plot.
It makes a cool noise when its seed pods are popping. Although I have tried, not recently, I have not been able to actually see a seed pod open. The vetch is an import by DOT about 1994 from Pennsylvania for one of its highway projects. From there it has been spread everywhere that cars go, such as past my yard. It’s a climbing vine of sorts and drags weaker plants to the ground.
Good old-fashioned pyrolysis works, if you don't mind the end product being methanol.
Ethanol is a terrible fuel. And with current technology, plants high in sugar or starch would be best. I doubt that any of the grasses would be good for it.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.