Energy Crops for Biofuels
A number of energy crops can potentially be grown on marginal land (i.e. land that is not suitable for food production) to provide feedstocks for bioenergy, non-food products and biofuels. Examples are shown below.
Miscanthus and Switchgrass
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CPL Press
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. Othe giant grasses such as Switchgrass are also the
subject of trials.
Sweet Sorghum
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SWEETFUEL
Sweet sorghum, as a source of either fermentable free sugars or lignocellulosics,
has many potential advantages, including: high water, nitrogen and radiation
use efficiency; broad agro-ecological adaptation; rich genetic diversity
for useful traits; and the potential to produce fuel feedstock, food
and feed in various combinations. Further research on Sweet Sorghum is
being carried out by SWEETFUEL
- Sweet sorghum: an alternative energy crop (FP7 - 227422)
Jatropha
Blooms of the Jatropha tree. Jatropha curcas is a tropical plant that grows well on marginal land, is drought tolerant and has seeds with high oil content (~40%). Although the plant contains toxins, and has to be handled and processed with care, Jatropha is considered a good candidate as a biofuels feedstock and is the subject of various trials. For example, Archer Daniels Midland (ADM), Bayer CropScience AG and Daimler AG announced in early 2009 that they would collaborate on use of Jatropha. NesteOil is also researching the use of Jatropha for biodiesel production.
Short Rotation Coppice
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Choren
Willow and poplar may be grown and
harvested in 2-5 year cycles as an energy crop (Short Rotation Coppice).
SRC has potential for use as a feedstock
for second generation biodiesel, for example as being demonstrated
at the Choren BtL
plant.
Sugar Cane
Sugar cane harvesting. Although sugar cane is a first generation crop, it is generally considered to be sustainable as it offers a high energy balance and high GHG reduction. It has not been shown to have significant impact on food supply or prices in Brazil, where there are 9 million vehicles that use ethanol or ethanol blends from sugar cane.
Improving the sustainablility of first generation feedstocks
Although expansion of first generation biofuels has decreased since 2008, biodiesel and bioethanol are still produced from crops in existing plants (manufacturing facilities). In the medium term, a number of initiatives have been instigated to make feedstocks more sustainable, until second generation biofuels are available on a commercial scale.
Sustainable winter oilseed rape - 24 page brochure (2007) joint publication of Unilever N.V., and UFOP( UNION ZUR FÖRDERUNG VON OEL- UND PROTEINPFLANZEN E. V.). Also available for download in German (2.3 Mb PDF).