Box 2: Biotechnology applications for biofuels

Many existing biotechnologies can be applied to improve bioenergy production, for example, in developing better biomass feedstocks and improving the efficiency of converting the biomass to biofuels.

Biotechnologies for first-generation biofuels

The plant varieties currently used for first- generation biofuel production have been selected for agronomic traits relevant for food and/or feed production and not for characteristics that favour their use as feedstocks for biofuel production. Biotechnology can help to speed up the selection of varieties that are more suited to biofuel production – with increased biomass per hectare, increased content of oils (biodiesel crops) or fermentable sugars (ethanol crops), or improved processing characteristics that facilitate their conversion to biofuels. The field of genomics – the study of all the genetic material of an organism (its genome) – is likely to play an increasingly important role. Genome sequences of several first- generation feedstocks, such as maize, sorghum and soybean, are in the pipeline or have already been published. Apart from genomics, other biotechnologies that can be applied include marker-assisted selection and genetic modification.

Fermentation of sugars is central to the production of ethanol from biomass. However, the most commonly used industrial fermentation micro-organism, the yeast Saccharomyces cerevisiae, cannot directly ferment starchy material, such as maize starch. The biomass must first be broken down (hydrolysed) to fermentable sugars using enzymes called amylases. Many of the current commercially available enzymes, including amylases, are produced using genetically modified micro-organisms. Research continues on developing efficient genetic yeast strains that can produce the amylases themselves, so that the hydrolysis and fermentation steps can be combined.

Application of biotechnologies for second-generation biofuels

Lignocellulosic biomass consists mainly of lignin and the polysaccharides cellulose (consisting of hexose sugars) and hemicellulose (containing a mix of hexose and pentose sugars). Compared with the production of ethanol from first-generation feedstocks, the use of lignocellulosic biomass is more complicated because the polysaccharides are more stable and the pentose sugars are not readily fermentable by Saccharomyces cerevisiae. In order to convert lignocellulosic biomass to biofuels the polysaccharides must first be hydrolysed, or broken down, into simple sugars using either acid or enzymes. Several biotechnology-based approaches are being used to overcome such problems, including the development of strains of Saccharomyces cerevisiae that can ferment pentose sugars, the use of alternative yeast species that naturally ferment pentose sugars, and the engineering of enzymes that are able to break down cellulose and hemicellulose into simple sugars.

Apart from agricultural, forestry and other by-products, the main source of lignocellulosic biomass for second- generation biofuels is likely to be from “dedicated biomass feedstocks”, such as certain perennial grass and forest tree species. Genomics, genetic modification and other biotechnologies are all being investigated as tools to produce plants with desirable characteristics for second- generation biofuel production, for example plants that produce less lignin (a compound that cannot be fermented into liquid biofuel), that produce enzymes themselves for cellulose and/or lignin degradation, or that produce increased cellulose or overall biomass yields.

Sources: based on FAO, 2007a The Role of Agricultural Biotechnologies for Production of Bioenergy in Developing Countries. Seminar, 12 October 2007, Rome, Italy. Organized by the FAO Working Group on Biotechnology and the FAO Working Group on Bioenergy. Rome (seminar papers available at ), and The Royal Society, 2008.

Source: FAO, The State of Food and Agriculture, Biofuels: Prospects, Risks and Opportunities (2008) , Chapter 2, potential for bioenergy, p.20

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Other Figures & Tables on this publication:

TABLE 1: Biofuel production by country, 2007

TABLE 2: Biofuel yields for different feedstocks and countries

TABLE 3: Hypothetical potential for ethanol from principal cereal and sugar crops

TABLE 4: Voluntary and mandatory bioenergy targets for transport fuels in G8+5 countries

TABLE 5: Applied tariffs on ethanol in selected countries

TABLE 6: Total support estimates for biofuels in selected OECD economies in 2006

TABLE 7: Approximate average and variable rates of support per litre of biofuel in selected OECD economies

TABLE 8: Energy demand by source and sector: reference scenario

TABLE 9: Land requirements for biofuel production

TABLE 10: Water requirements for biofuel crops

TABLE 11: Import bills of total food and major food commodities for 2007 and their percentage increase over 2006

TABLE 12: Net importers of petroleum products and major cereals, ranked by prevalence of undernourishment

TABLE 13: Share of net staple food-seller households among urban, rural and total households

Box 1: Other types of biomass for heat, power and transport

Box 2: Biotechnology applications for biofuels

Box 3: Biofuel policies in Brazil

Box 4: Biofuel policies in the United States of America

Box 5: Biofuel policies in the European Union

Box 6: Main sources of uncertainty for biofuel projections

Box 7: Biofuels and the World Trade Organization

Box 8: Biofuels and preferential trade initiatives

Box 9: The Global Bioenergy Partnership

Box 10: Biofuels and the United Nations Framework Convention on Climate Change

Box 11: Jatropha – a “miracle” crop?

Box 12: Agricultural growth and poverty reduction

Box 13: Cotton in the Sahel

Box 14: Biofuel crops and the land issue in the United Republic of Tanzania

Figure 1: World primary energy demand by source, 2005

Figure 2: Total primary energy demand by source and region, 2005

Figure 3: Trends in consumption of transport biofuels

Figure 4: Biofuels – from feedstock to end use

Figure 5: Uses of biomass for energy

Figure 6: Conversion of agricultural feedstocks into liquid biofuels

Figure 7: Estimated ranges of fossil energy balances of selected fuel types

Figure 8: Support provided at different points in the biofuel supply chain

Figure 9: Biofuel production costs in selected countries, 2004 and 2007

Figure 10: Breakeven prices for crude oil and selected feedstocks in 2005

Figure 11: Breakeven prices for maize and crude oil in the United States of America

Figure 12: Breakeven prices for maize and crude oil with and without subsidies

Figure 13: Maize and crude oil breakeven prices and observed prices, 2003–08

Figure 14: Price relationships between crude oil and other biofuel feedstocks, 2003-08

Figure 15: Food commodity price trends 1971–2007, with projections to 2017

Figure 16: Global ethanol production, trade and prices, with projections to 2017

Figure 17: Major ethanol producers, with projections to 2017

Figure 18: Global biodiesel production, trade and prices, with projections to 2017

Figure 19: Major biodiesel producers, with projections to 2017

Figure 20: Total impact of removing trade-distorting biofuel policies for ethanol, 2013–17 average

Figure 21: Total impact of removing trade-distorting biofuel policies for biodiesel, 2013–17 average

Figure 22: Life-cycle analysis for greenhouse gas balances

Figure 23: Reductions in greenhouse gas emissions of selected biofuels relative to fossil fuels

Figure 24: Potential for cropland expansion

Figure 25: Potential for yield increase for selected biofuel feedstock crops

Figure 26: Potential for irrigated area expansion

Figure 27: Agricultural trade balance of least-developed countries

Figure 28: Distribution of poor net buyers and sellers of staple foods1

Figure 29: Average welfare gain/loss from a 10 percent increase in the price of the main staple, by income (expenditure) quintile for rural and urban households