Cellulosic crops for production of advanced biofuels
This page is currently being developed. Cellulosic crops include energy grasses, reeds and similar crops that may be grown on marginal lands. Cellulosic crops may be used as additional feedstocks in facilities that convert straw and stover into cellulosic ethanol. Examples include Miscanthus, Switchgrass, Elephant Grass, Giant reedgrass, etc) as discussed below.
Miscanthus (above) has been trialled extensively in Europe and the US as an energy crop for biofuel production. Trials indicate that that it provides relatively high yields (double that of corn), requires limited fertiliser, few other inputs and adds significant amounts of organic matter to the soil. Other giant grasses such as Switchgrass are also the subject of trials.
A ten year trial of Miscanthus (2003-2013) by University of Illinois showed an average annual yeild of 10.5 tons per acre (double that of a corresponding area planted with Switchgrass). The trial confirmed that Miscanthus grows well with little or no fertiliser input. After five years, the roots and rhizomes contribute 12 tons of biomass per acre to the soil (dry mass). The extensive root system of Miscanthus makes it suitable for stabilizing slopes or soils.
In March 2012 it was announced Mendel Biotechnology (Mendel Bioenergy Seeds) will carry out a 4-year field trial of PowerCane™ Miscanthus with BP Biofuels, as a potential feedstock for the cellulosic ethanol demonstration plant in Jennings.
Panicum virgatum (Switchgrass)
Extensive research is being carried out into cultivation of Switchgrass as a biofuels feedstock in the US. The plant is a tall-growing, perennial grass that is native to North America.
In summer 2014, USDA announced a new Switchgrass variety "Liberty", which can yield 8 tons per acre, and offers improved winter hardiness.
Samuel Roberts Noble Foundation has developed novel strains of switchgrass that contain lower amounts of lignin and hence boost biofuel yields by over a third [Source: Proceedings of the National Academy of Sciences].
Following a $5m grant from the DOE in 2009, University of Tennessee and Genera Energy have developed a new feedstock logistics systems using chopped switchgrass, which aims to bridge the gap between growers and biofuel producers.
Pennisetum purpureum (Giant King Grass, Napier Grass, Elephant Grass)
In California, Viaspace Inc. is developing projects using Giant King Grass as a feedstock for advanced biofuels, and biomethane for energy production.
Arundo donax (Giant reedgrass)
Giant reedgrass (Spanish cane) is considered to be one of the most promising species for biomass production in Europe. It is being cultivated as a feedstock for the Beta Renewables commercial scale cellulosic ethanol plant in Crescentino.
Phalaris arundinacea (Reed canary grass)
Phalaris arundinacea (Reed canary grass), provides good yields on poor soils and contaminated land and is thus an interesting candidate for bioremediation of brownfield sites as well as a source of biomass for bioenergy (typically as briquettes) or pulp. Is also considered a suitable feedstock for cellulosic ethanol production [Source: VTI Finland].
Cynara cardunculus (Cardoon)
Cynara cardunculus (Cardoon) has been investigated as an energy crop for co-firing with lignite at the PPC Kardia Power Plant, Greece, as part of the FP6 DEBCO project. The oil, extracted from the seeds of the cardoon (artichoke oil) has also been investigated as a feedstock for biodiesel production.