|
||||||
 |
||||||
 |
||||||
|
||||||
|
||||||
News and Trends
http://www.thebioenergysite.com/articles/967/new-biofuel-sustainability-assessment-tool A team of researchers from the Swiss Federal Laboratories for Materials Science and Technology (EMPA), the Swiss Roundtable on Sustainable Biofuels (RSB) and Hochschule für Technik und Wirtschaft (HTW) Berlin, Germany, recently developed an online tool that would let biofuel stakeholders or any interested party to assess the sustainability of biofuel production. The new online tool, which took about two years to develop and was supported by the Swiss State Secretariat for Economic Affairs (SECO), allows users to perform three different functions: (1) Self-assessment of biofuel production against the principles and criteria of the RSB, (2) Risk Assessment in biofuel production, and (3) Calculation of greenhouse gas (GHG) emissions of biofuels for each life cycle production step (i.e. from farming to final fuel distribution) using various methodology. The RSB Standard, which is used in the first function of the tool, comprises 12 principles and criteria for sustainable biofuel production, including environmental and social principles such as food security and human and labor rights. By allowing a risk assessment of biofuels production and an evaluation based on the RSB sustainability principles, the tool serves as a starting point in obtaining a RSB sustainability certification. The online tool can be accessed at the EMPA website (URL above). An English language option is available at the top link of the EMPA webpage.
http://iopscience.iop.org/1748-9326/6/2/024010/pdf/1748-9326_6_2_024010.pdf Researchers from the University of Texas, Michigan State University, and Kansas State University (United States) report the use of a "spatial regression model" on agricultural bioenergy crop and deforestation data (from 2003 to 2008), to demonstrate that indirect land use change (ILUC) effects due to increased demand for biofuels is "significant and of considerable magnitude" in the Brazilian Amazon. Indirect land use change is a term which, based on a logic states that the increase in demand of biofuel crops in one area can lead to land conversions that are utilized for planting more biofuel crops in another area; or the demand can lead to land conversions that can displace other crops (also in another area). For example, the increase in the planting of corn for use as biofuel ethanol in the United States can displace other crops, like soybeans. This can cause farmers in other countries, such as Brazil, to cut down rainforests to grow soybeans and compensate for the "soybean displacement" in the United States. Thus, sometimes, the "land conversions" lead to deforestation, and the destruction of forest cover results in a reduced capacity of the earth to reduce carbon dioxide from the atmosphere. It would take years to regain this loss in capacity through reforestation, as trees take a long time to grow and mature. This period of time for reforestation to regain capacity to absorb (reduce) carbon dioxide from the atmosphere has been termed as the "carbon payback period". The researchers are reported to have"statistically linked the loss of forest area as the indirect effect of changing pasture land into space for soybean and biofuel crops in countries bordering the Amazon." Their model also indicated that the 40% of heavily forested countries in the Brazilian Amazon could have been saved by a 10% reduction of soybean plantations on old pasture areas. The complete findings of the study are published in the journal, Environmental Letters (URL above). Related information on Indirect Land Use Change (ILUC) can be seen at http://eponline.com/articles/2009/05/12/indirect-land-use-change.aspxhttp://www.greencarcongress.com/2009/02/perspective-ind.html Energy Crops and Feedstocks for Biofuels Production
(full access to article may require payment or subscription) Majority of the commercially available biofuels today are derived from food crops such as corn, sugarcane and rapeseed. However, due to food security concerns and increase in the demand of biofuels, there is a need to find alternative feedstock for biofuels. One of the crops that is predicted to have a significant contribution to world energy is the perennial grass of the genus Miscanthus. This grass originated in Eastern Asia, and has about a dozen species. It is also seen as a potential bioenergy feedstock because of its desirable characteristics, such as, high yield, cold tolerance, low environmental impact, and ease of harvesting and handling. In anticipation of the increase in the use of Miscanthus as a biofuel feedstock, researchers from the Faculty of Science, Department of Agroecology and Environment, Aarhus University, Denmark attempted to assess the benefits and risks of growing Miscanthus. In their study, they first gave an overview of the genus Miscanthus, along with the possible uses of this crop and its benefits. The researchers discussed possible risks that go along with the growing of Miscanthus and later pinpointed avenues for improvement in the cultivation of Miscanthus. Among the highlights of the research are: (1) Miscanthus giganteus is the best species as bioenergy crop due to its non-invasiveness, pest and disease resistance and low emission characteristics, (2) risks of growing Miscanthus include fire in mature crop, high water use and it could serve as vector for disease in other plants,(3) avenues for risk minimization include early harvest, monitoring and stewardship programs, growing in restricted location and breeding programs. The full paper is published in the journal, Current Opinion in Environmental Sustainability (URL above). Biofuels Processing
(full access to article may require payment or subscription) Researchers from the Department of Chemical Engineering, Lund University, Sweden investigated the effect of the presence of ferrous sulfate on sugar yields in the dilute-acid pretreatment of softwood (Picea abies) for the production of bioethanol. Pretreatment is a key process in biofuel production in which carbohydrates are liberated from the tight lignin wrapping. The liberated carbohydrates (mainly cellulose and hemicellulose) are then converted to simple sugars by a process called, "enzymatic saccharification", and the sugars are eventually fermented to ethanol. Among the types of pretreatment, one of the most promising method for commercialization is the dilute-acid pretreatment. Addition of inorganic salts such as ferrous sulfate can be used In order to improve dilute acid pretreatment. In their paper, the Swedish researchers compared the sugar yields with and without the presence of ferrous sulfate during the pretreatment of softwood, . They performed the pretreatment experiments using two catalysts: (1) Sulfuric acid (H2SO4), and (2) combination of sulfurtrioxide (SO3) and sulfurous acid (H2SO3). Results showed that using H2SO4catalyst, the sugar yields from the pretreatment was not improved. On the other hand, the sugar yield from softwood pretreatment using SO3-H2SO3catalyst increased from 73.9% to 78.5% of the theoretical value. The full paper is published in the journal, Bioresource Technology (URL above).
(full access to article may require payment or subscription) A team of researchers from Taiwan (Institute of Biological Chemistry & Genomic Research Center, Academia Sinica; Department of Food Science, Fu Jen Catholic University; and Institute of Biochemical Sciences, College of Life Science, National Taiwan University) and Thailand (Division of Biochemical Technology, School of Bioresources and Technology, King Mongkut's University of Technology) recently investigated the effect of membrane entrapment on enzyme activity in the enzymatic treatment step of bioethanol production. Enzymatic treatment is the second step in bioethanol production (after pretreatment) in which enzymes break carbohydrate molecules down into the component monosaccharides. However, due to the high cost of enzymes, it is important to increase enzyme activity to lower the cost of bioethanol production. The researchers studied the difference in enzyme activity of free and entrapped lignocellulolytic enzymes (cellulase, xylanase and laccase) at operating conditions of 37oC and pH 5.5. They found that the activity for entrapped enzymes increased by an average of 57.92%, 19.39% and 20.34% for cellulase, xylanase and lactase, respectively, compared to the free enzymes.This translated to an increase in monosaccharide production by 29% or from 465.46mg/g rice straw to 601.05mg/g rice straw. From the results of this study, enzyme entrapment, according to the researchers, is a practical way to improve the biocatalytic properties (such as activity, stability and reusability) of enzymes used for the hydrolysis of rice straw and to separate the products from the reaction medium. The full paper is published in the journal, BioresourceTechnology (URL above). Biofuels Policy and Economics
(full access to article may require payment or subscription) Researchers from the Department of Geography, Faculty of Arts and Science, Queen's University, Queen's Institute for Energy and Environmental Policy, Canada have recently proposed a method of assessing the feasibility of bioenergy resources with considerations for spatial/geographic location. Since bioenergy resources are spatially distributed and their potential to contribute to societal energy supplies is dependent on local geographic nuances, it is imperative to include the geographic location to help assess biofuel feasibility. By incorporating geographic information about a target area for biofuel production, fundamental bioenergy measurement problems such as distinguishing actual from potential feedstock, quantifying multiple biomass supply options, and assessing the overwhelming scope of bioenergy conversion platforms and technological configurations from which useable forms of energy are made available, are being alleviated. In their paper, the researchers first presented the computation of the theoretical energy availability (i.e. the total energy content per unit area from a given energy source option at any moment in time) for the three major sources of bioenergy, which are forest fuels, agricultural fuels, and bio-wastes. They enumerated spatial, ecological, economic, and harvesting restrictions that would limit the theoretical available energy to the exploitable energy available. Restrictions pertaining to the inefficiencies involved in the conversion of the energy into useful energy were taken into account, thus obtaining the net-yield bioenergy availability, a parameter which can be used as a basis for candidate site selection of bioenergy facilities. Finally, the researchers discussed the credibility of the assumptions and models used in the bioenergy assessment of a particular site. This method of bioenergy feasibility assessment, according to the researchers, will serve as baseline information to enable bioenergy to be taken seriously in energy investment decisions. The full paper is published in the journal, Renewable and Sustainable Energy Reviews (URL above).
(full access to article may required subscription or payment) Many countries in Latin America have established their own national programs for the promotion and use of biofuels, in the hope that they could also duplicate the success of the Brazilian biofuels program, both locally and globally. Biofuel-ethanol production from sugarcane is being targeted by Colombia, Venezuela, Costa Rica and Guatemala. Argentina is focusing on soybean-biodiesel. Soybean and (in a way) sugarcane are bioenergy crops that are partially food-based, and therefore may have possible sustainability issues. The issue of biofuel-sustainability has important future implications in Latin American countries which cultivate these bioenergy crops. Certification schemes are being proposed (for example in some European countries) to ensure that only sustainably produced biofuels can be traded. Researchers from WIP Renewable Energies (Germany) present an "an overview of the hotspots of conflicts in biofuel production in Latin America", and an evaluation of tools/initiatives to ensure sustainable production in the continent. Among the findings of the study are: (1) potential negative impacts which go against sustainable biofuels production in Latin America include: deforestation of the Amazon forest, degradation of the Cerrado, displacement of indigenous communities and the food–fuel conflict; (2) Industry stakeholders and governments in Latin America have initiated some sustainability initiatives to minimize the negative impacts. These include, the "Amazon Moratorium", the "Verified Sustainable Ethanol Initiative", and the "Round Table on Responsible Soy". Although many of the initiatives are done on a voluntary basis, they are reported to be important for improving "economic, environmental and social sustainability of biofuels production/use in Latin America"; (3) Implementation of sustainability schemes will be "beneficial for both domestic markets and for facilitating exports to the European market". The full report is published in the journal, Energy Policy (URL above). |
||||||
