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.
Will perennial crops take off in Europe?
View Presentation by Jean-Marc Jossart, General Secretary, AEBIOM, given at EBTP SPM4 on 15-09-11 (672 Kb PDF)
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.
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.
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].
Arundo donax (Giant reedgrass)
Arundo donax (Giant reedgrass or 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 M&G commercial scale cellulosic ethanol plant in Crescentino.
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)
Sweet Sorghum is also being developed as a biofuel feedstock in the US (e.g. Regional Strategy for Biobased Products in the Mississippi Delta).
Short Rotation Coppice
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 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.
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].
Camelina sativa is an oil plant that grows well on marginal land, is cold-tolerant and has an oil-yield of 35-38%. It is being investigated as a sustainable oil crop for biodiesel production. Picture credit: Wikipedia.
Sustainable Oils (a partnership between Targeted Growth, Inc. and Green Earth Fuels, LLC) currently has 30 Camelina breeding trials in the US and Canada. The company provided Camelina-based biodiesel for a Japan Airlines test flight in January 2009.
The Eureka BIOFUEL-CAMELINA Project, coordinated by ISCO, Poland,
is studying the cultivation of Camelina sativa and cameline oil production, biofuel production and evaluation. Biojet fuel derived from Camelina has been successfully used on demonstration flights.
Images of Jatropha curcas © copyright JatroSolutions GmbH, which offers expertise in tropical plant production, including cultivation of Jatropha for biofuel production. The top picture shows pollination of Jatropha by bees. The picture immediately above shows male flower (right) and female flower (left).
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. Galp Energia, Portugal is leading a research project on Jatropha for biofuels production in Mozambique.
*In Singapore, Temasek Life Sciences Laboratory and JOil Pte Ltd. have developed Jatropha strains with 75% oleic acid content, compared to the typical 45% percent (May 2012).
Salicornia bigelovii (dwarf saltwort / dwarf glasswort)
A salt mash halophyte that is found on both the east and west coast of the US and Mexico. The plant is of interest as a biofuel feedstock as it grows in desert environments, can be irrigated with seawater, and the seed contains around 30% oil content. It is being grown extensivley across the globe, for example in India.
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.
Brassica carianata (Ethiopian mustard)
Brassica carianata oilseed has been developed as a biofuel feedstock ( Resonance™) by Agrisoma Biosciences (Canada). It is suited to semi-arid areas and produces seed with 44% oil content. In April 2012 Agrisoma announced that Resonance™ will be evaluated as a feedstock for Honeywell Green Jet Fuel™.
Castor oil is also being developed as a potential industrial-scale biofuel feedstock. "Castor bean is a non-edible, high oil-yielding crop (40%-50% seed oil content) with high tolerance for growth under harsh environmental conditions, such as low rainfall and heat" [Source: Evogene].
FP7 Projects on energy crops
ENERGYPOPLAR aims to develop energy poplar trees with both desirable cell-wall traits and high biomass yield under sustainable low-input conditions to be used as a source of cellulosic feedstock for bioethanol production.
SWEETFUEL Sweet sorghum: an alternative energy crop (FP7 - 227422)
Virtual Modelling of Energy Crops
The Eureka E-PLANTS project led by Intesys has produced a 3D model of the virtual plant growth, enabling biofuel feedstock growers to visualise the complex and dynamic interactions between different plant components and experiment quickly with the simultaneous influences of temperature, nutrient levels, moisture and other conditions on rooting and growth.
Carbo-BioCrop project in the UK
Carbo-BioCrop will provide information on the carbon mitigation potential of bioenergy crops. The project is funded as part of the Living With Environmental Change (LWEC) project in the UK. The aim of Carbo-BioCrop is to gain a better understanding of the processes that cause changes in soil organic carbon (SOC) and emmissions of GHGs (CO2, N2O and CH4) under Short Rotation Coppice (willow, poplar) and Miscanthus. In particular, such changes will be quantified when land is converted from arbale or grassland to energy crops.
Support for Energy crops in the United States
In October 2010, USDA published a final rule to implement the Biomass Crop Assistance Program (BCAP). Under the BCAP final rule, USDA will resume making payments to eligible producers. The program had operated as a pilot, pending publication of the final rule. Authorized in the Food, Conservation, and Energy Act of 2008, BCAP is designed to ensure that a sufficiently large base of new, non-food, non-feed biomass crops is established in anticipation of future demand for renewable energy consumption.
Domestic production of renewable energy, including biofuels, is seen as a national imperative the USDA aims to help develop a thriving biofuels industry in every part of the US. A recent USDA report indicated that the initiative will will create jobs, combat global warming, replace our dependence on oil imports and boost the economy [Source: USDA].
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).