Turning weeds into ethanol - why not?
The Department of Agricultural and Consumer Economics, University of Illinois Urbana-Champaign looked at another option for ethanol production – weeds.
Weeds are out there. These scientists are looking at another way to dispose of them, so why not create ethanol from them?
Utilizing certain non-native weeds for bioenergy is “as pervasive as invasiveness itself.” The process of using weeds for ethanol production can be daunting. It would require extensive record keeping, monitoring to make sure weeds don’t spread, and continuous reporting by land owners.
The article uses prior research summaries to pose questions and concerns but recognizes that many studies on ethanol have not addressed the economic, ecological, or practical possibility of using non-native feedstocks for bioenergy.
Only a handful of ethanol plants have the power and technology to handle cellulosic feedstocks (such as weeds). These cellulosic biorefineries are few and far between, causing some logistical issues.
They require an abundance of weeds (1,800 to 9,000 MT biomass per day) to consistently be delivered. This equals an estimated 70,000 to 350,000 hectares of, in this case, weeds to be harvested each year. Considering these invasive weeds that most farmers would prefer to eradicate are scattered across many hectares, not to mention private boundaries, harvesters would need to negotiate with numerous property owners. This leaves uncertainty of availability and consistency of supplies.
Labor and processing costs could put a blunder in the possibility of weeds for ethanol as well. While the weeds are non-native and not wanted, they are typically among native plants, some of which may be rare or endangered. Many invasive plant removal projects require volunteers to go out into a field and remove weeds by hand. However, to harvest enough plants for ethanol production mechanization will be required. This separation process will add even more to the already daunting labor costs.
Let’s say that there were enough weeds to make a go of it. Invaders that are declared “noxious” on a state or federal level are technically not permitted to be sold or cross state lines. To complicate things further, interstate compacts would be needed to transport noxious weeds to the widely-dispersed facilities.
Removal of these weeds could benefit the ethanol industry as well as the native plants in the area. There is the possibility that these plants can uncontrollably spread, much like the herbicide-resistant marestail. If recommended management practices are not followed, not only can weeds spread, dormant seeds can sprout and native plants could undergo unnecessary stress, aiding invaders further.
Read the full article: http://farmdocdaily.illinois.edu/2013/12/turning-weeds-into-ethanol-why-not.html