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5. Environmental Impacts of Biofuels

5. Environmental Impacts of Biofuels

: PROSPECTS, RISKS AND OPPORTUNITIES 55

5. Environmental impacts of biofuels

Although production remains small Depending on the methods used to produce in the context of total energy demand, it the feedstock and process the , some is significant in relation to current levels can even generate more of agricultural production. The potential gases than do fossil . For example, environmental and social implications of its nitrous oxide, a with a global- continued growth must be recognized. For warming potential around 300 times greater example, reduced than that of , is released from are among the explicit goals of some policy nitrogen fertilizers. Moreover, greenhouse measures to support biofuel production. gases are emitted at other stages in the Unintended negative impacts on land, water production of crops and biofuels: and count among the side-effects in producing the fertilizers, and fuel of agricultural production in general, but used in farming, during chemical processing, they are of particular concern with respect to transport and distribution, up to final use. biofuels. The extent of such impacts depends Greenhouse gases can also be emitted by on how biofuel feedstocks are produced direct or indirect land-use changes triggered and processed, the scale of production and, by increased biofuel production, for example in particular, how they influence land-use when carbon stored in forests or is change, intensification and international released from the during land conversion trade. This chapter reviews the environmental to production. For example, while implications of biofuels; the social implications produced for can generate will be considered in the following chapter. greenhouse gas savings of about 1.8 of carbon dioxide per hectare per year, and switchgrass – a possible second-generation Will biofuels help mitigate climate crop – can generate savings of 8.6 tonnes change?10 per hectare per year, the conversion of to produce those crops can release Until recently, many policy-makers assumed 300 tonnes per hectare, and conversion of that the replacement of fossil fuels with forest land can release 600–1 000 tonnes fuels generated from would have per hectare (Fargione et al., 2008; The Royal significant and positive climate-change Society, 2008; Searchinger, 2008). effects by generating lower levels of the Life-cycle analysis is the analytical tool greenhouse gases that contribute to global used to calculate greenhouse gas balances. warming. Bioenergy crops can reduce or The greenhouse gas balance is the result offset greenhouse gas emissions by directly of a comparison between all emissions of removing carbon dioxide from the air as greenhouse gases throughout the production they grow and storing it in crop biomass and phases and use of a biofuel and all the soil. In addition to biofuels, many of these greenhouse gases emitted in producing and crops generate co-products such as using the equivalent energy amount of the for , thus saving on energy that respective . This well-established, would have been used to make feed by other but complex, method systematically means. analyses each component of the value Despite these potential benefits, however, chain to estimate greenhouse gas emissions scientific studies have revealed that different (Figure 22). biofuels vary widely in their greenhouse The starting point in estimating the gas balances when compared with petrol. greenhouse gas balance is a well-defined set of boundaries for a specific biofuel 10 The analysis in this section draws partly on FAO (2008d). system, which is compared with a suitable 56 THE STATE OF AND 2008

“conventional” reference system – in most A limited number of studies have considered cases petrol. Several biofuel feedstocks also oil; from , generate co-products, such as press cake and jatropha; and biomethane from . or feed. These are considered Given the wide range of biofuels, feedstocks “avoided” greenhouse gas emissions and and production and conversion technologies, are assessed by comparing them with similar we would expect a similarly wide range of stand-alone products or by allocation (e.g. by outcomes in terms of emission reductions – energy content or market price). Greenhouse which is indeed the case. Most studies have gas balances differ widely among crops found that producing first-generation and locations, depending on feedstock biofuels from current feedstocks results production methods, conversion technologies in emission reductions in the range of 20– and use. Inputs such as nitrogen fertilizer 60 percent relative to fossil fuels, provided the and the type of (e.g. most efficient systems are used and carbon from or oil, or nuclear) used to convert releases deriving from land-use change are feedstocks to biofuels may result in widely excluded. Figure 23 shows estimated ranges varying levels of greenhouse gas emissions of reduction in greenhouse gas emissions for and also differ from one region to another. a series of crops and locations, excluding the Most life-cycle analyses of biofuels, to effects of land-use change. , which has date, have been undertaken for and long experience of producing ethanol from oilseeds in the EU and the of , shows even greater reductions. America and for sugar-cane ethanol in Brazil. Second-generation biofuels, although still

FIGURE 22 Life-cycle analysis for greenhouse gas balances

Life-cycle analysis for conventional fossil fuel

Crude oil Conventional Transport extraction fossil fuel Use in for Refining and (petrol transport processing pre-treatment or diesel)

GREENHOUSE GAS EMISSIONS

Feedstock production: land, fertilizer, Biofuel Ethanol pesticides, Transport processing: or Land-use Use in , for , biodiesel change transport machinery, processing chemicals, and fuel energy use co-products

Life-cycle analysis for liquid biofuel

Source: FAO. BIOFUELS: PROSPECTS, RISKS AND OPPORTUNITIES 57

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

Sugar cane, Brazil Second-generation biofuels

Palm oil

Sugar beet, , European Union Maize

Maize, United States of America

-100-90 -80-70 -60-50 -40-30 -20-10 0 Percentage reduction

Note: Excludes the effects of land-use change. Sources: IEA, 2006, and FAO, 2008d. insignificant at the commercial level, typically in subsequent stages of production and use. offer emission reductions in the order of 70– When land-use changes are included in the 90 percent, compared with fossil diesel and analysis, greenhouse gas emissions for some petrol, also excluding carbon releases related biofuel feedstocks and production systems to land-use change. may be even higher than those for fossil Several recent studies have found that the fuels. Fargione et al. (2008) estimated that most marked differences in results stem from the conversion of , peatlands, allocation methods chosen for co-products, savannahs or grasslands to produce ethanol assumptions on nitrous oxide emissions and and biodiesel in Brazil, , Malaysia land-use-related carbon emission changes. or the United States of America releases at At present, a number of different methods least 17 times as much carbon dioxide as are being used to conduct life-cycle analysis those biofuels save annually by replacing and, as noted above, some of these do fossil fuels. They find that this “carbon not consider the complex topic of land-use debt” would take 48 years to repay in the change. The parameters measured and the case of Conservation Reserve Program land quality of the data used in the assessment returned to maize ethanol production in the need to comply with set standards. Efforts United States of America, over 300 years to are under way within, among others, the repay if Amazonian is converted Global Bioenergy Partnership, to develop for , and over a harmonized methodology for assessing 400 years to repay if tropical peatland greenhouse gas balances. There is a similar rainforest is converted for palm-oil biodiesel need for harmonization in assessing the production in Indonesia or Malaysia. broader environmental and social impacts Righelato and Spracklen (2007) estimated of bioenergy crops to ensure that results are the carbon emissions avoided by various transparent and consistent across a wide ethanol and biodiesel feedstocks grown on range of systems. existing cropland (i.e. sugar cane, maize, In assessing greenhouse gas balances, and for ethanol, and the data on emissions emanating from rapeseed and woody biomass for diesel). land-use change are crucial if the resulting They found that, in each case, more carbon picture is to be complete and accurate. Such would be sequestered over a 30-year period emissions will occur early in the biofuel by converting the cropland to forest. They production cycle and, if sufficiently large, argue that if the objective of biofuel support may require many years before they are policies is to mitigate global warming, compensated by emissions savings obtained then fuel efficiency and forest conservation 58 THE STATE OF FOOD AND AGRICULTURE 2008

BOX 9 The Global Bioenergy Partnership

The Global Bioenergy Partnership to Markets Partnership, the (GBEP), launched at the 14th session Policy Network for of the United Nations Commission on the 21st Century, the Renewable Energy in May 2006, is and Energy Efficiency Partnership, the an international initiative established to United Nations Conference on Trade implement the commitments taken by the and Development (UNCTAD) BioFuels G8+5 countries1 in the 2005 Gleneagles Initiative and the Bioenergy Implementing Plan of Action. It promotes global high- Agreements and related tasks of the level policy dialogue on bioenergy; International Energy Agency, among supports national and regional bioenergy others. In addition, the Partnership policy-making and market development; has formed a task force to work on favours efficient and sustainable uses harmonizing methodologies for life-cycle of biomass; develops project activities analysis and developing a methodological in bioenergy; fosters bilateral and framework for this purpose. All these multilateral exchange of information, initiatives provide important avenues for skills and technology; and facilitates assisting both developing and developed bioenergy integration into energy markets countries in building national regulatory by tackling specific barriers in the supply frameworks for bioenergy. chain. The Partnership is chaired by , and FAO is a Partner and hosts the GBEP Secretariat. GBEP cooperates with FAO’s International Bioenergy Platform, 1 The G8+5 group comprises the G8 countries the International Biofuels Forum, (, , , Italy, Japan, the the International Partnership for the Russian Federation, the United Kingdom and the United States of America), plus the five major , the Mediterranean emerging (Brazil, , , Renewable Energy Programme, the and ).

and restoration would be more effective be as high as US$4 520 in the EU (ethanol alternatives. from sugar beet and maize) – much higher Among the options for reducing than the market price of carbon dioxide- greenhouse gas emissions that are currently equivalent offsets. Enkvist, Naucler and being discussed, biofuels are one important Rosander (2007) report that relatively alternative – but in many cases improving straightforward measures to reduce energy energy efficiency and conservation, consumption, such as better insulation of increasing carbon sequestration through new buildings or increased efficiency of or changes in agricultural heating and air-conditioning systems, have practices, or using other forms of renewable carbon dioxide abatement costs of less than energy can be more cost-effective. For €40 per . example, in the United States of America, Both the scientific and policy dimensions improving average vehicle-fuel efficiency by of sustainable bioenergy development are one mile per gallon may reduce greenhouse evolving rapidly (almost on a weekly basis). gas emissions as much as all current United A comprehensive understanding of the States ethanol production from maize relevant issues, including land-use change, (Tollefson, 2008). Doornbosch and Steenblik and proper assessment of greenhouse gas (2007) estimated that reducing greenhouse balances are essential in order to ensure gas emissions via biofuels costs over US$500 that bioenergy crops have a positive and in terms of subsidies per tonne of carbon sustainable impact on climate-protection dioxide in the United States of America efforts. The complexity of factors relating (maize-based ethanol) and the cost can to land-use change has led to its omission BIOFUELS: PROSPECTS, RISKS AND OPPORTUNITIES 59

from most bioenergy life-cycle analyses but the United States of America and the EU) it remains an essential piece of information have suggested that net greenhouse gas that governments need to consider in balances from biofuels should be in the range formulating national bioenergy policy. of 35–40 percent less than that of petrol. A In addition to the impacts of feedstock careful analysis of these issues is important production on greenhouse gas emissions, for all stakeholders, especially for exporters biofuel processing and distribution can of bioenergy crops or fuels, as a basis for also have other environmental impacts. As investment and production decisions and in the sector, the processing ensuring the marketability of their products. of biofuel feedstocks can affect local air quality with , particulates, nitrogen oxide, sulphates and volatile organic Land-use change and compounds released by industrial processes intensification (Dufey, 2006). However, to the extent that biofuels can replace traditional biomass The preceding section highlighted the such as fuelwood and charcoal, they also influence of land-use change on the hold potential for dramatic improvements greenhouse gas balances of biofuel in human health, particularly of women and production. When assessing the potential children, through reduced respiratory diseases emission effects of expanding biofuel and deaths caused by indoor air . production, a clear understanding is In some cases, national regulations needed of the extent to which increased require importers to certify the sustainable production will be met through improved cultivation of , the protection land productivity or through expansion of natural habitats and a minimum level of of cultivated area; in the latter case, carbon dioxide savings for biofuels. Some the category of land is also significant. countries and regional organizations (e.g. Agricultural production techniques also

BOX 10 Biofuels and the United Nations Framework Convention on

Although no international agreements in achieving sustainable development and specifically address bioenergy, the in contributing to the ultimate objective United Nations Framework Convention of the Convention, and to assist Parties on Climate Change (UNFCCC) guides included in Annex 1 in complying with Member States to “take climate-change their quantified emission limitation considerations into account, to the extent and emissions reduction commitments. feasible, in their relevant social, economic Since the inception of the CDM in 2005, and environmental policies and actions, energy-industry projects have dominated and employ appropriate methods ... with all project types registered in the CDM, a view to minimizing adverse effects on including those for bioenergy. Within the the economy, on public health and on the field of bioenergy, several methodologies quality of the environment of projects or are available for projects that use biomass measures undertaken by them to mitigate for energy generation, although there or adapt to climate change” (UNFCCC, are only a limited number of approved 1992, Article 4). The , which methodologies for biofuels. A biofuel expires in 2012, provides a robust and methodology based on waste oil is already modern framework for promoting clean available and a methodology for biofuel technologies such as those for renewable production from cultivated biomass is energy. under development. The Clean Development Mechanism (CDM), as one of the flexibility mechanisms within the Kyoto Protocol, was designed Source: FAO, based on a contribution from the to assist Parties not included in Annex 1 UNFCCC Secretariat. 60 THE STATE OF FOOD AND AGRICULTURE 2008

contribute to determining greenhouse gas already under cultivation and the conversion balances. Both factors will also determine of land not currently in crop production, such other environmental impacts relating to , as grassland or forest land. water and biodiversity. Over the past five decades, most of the Area expansion increase in global agricultural commodity Of the world’s 13.5 billion hectares of total production (around 80 percent) has resulted land surface area, about 8.3 billion hectares from yield increases, with the remainder are currently in grassland or forest and accounted for by expansion of cropped area 1.6 billion hectares in cropland (Fischer, and increased frequency of cultivation (FAO, 2008). An additional 2 billion hectares are 2003; Hazell and Wood, 2008). The rate of considered potentially suitable for rainfed growth in demand for biofuels over the past crop production, as shown by Figure 24, few years far exceeds historic rates of growth although this figure should be treated with in demand for agricultural commodities and considerable caution. Much of the land in crop yields. This suggests that land-use in forest, wetland or other uses provides change – and the associated environmental valuable environmental services, including impacts – may become a more important carbon sequestration, water filtration and issue with respect to both first- and second- biodiversity preservation; thus, expansion generation technologies. In the short term, of crop production in these areas could be this demand may be satisfied primarily detrimental to the environment. by increasing the land area under biofuel After excluding forest land, protected crops while in the medium and long term areas and land needed to meet increased the development of improved biofuel crop demand for food crops and livestock, varieties, changes in agronomic practices estimates of the amount of land potentially and new technologies (such as cellulosic available for expanded crop production lie conversion) may begin to dominate. between 250 and 800 million hectares, most Significant yield gains and technological of which is found in tropical or advances will be essential for the sustainable in Africa (Fischer, 2008). production of biofuel feedstocks in order Some of this land could be used directly to minimize rapid land-use change in areas for biofuel feedstock production, but

FIGURE 24 Potential for cropland expansion

Million ha 1 200

1 000

800

600

400

200

0 Latin Sub-Saharan Industrial Transition East Asia South Asia Near East America Africa countries countries and and the North Africa Caribbean

Arable land in use, 1997–99 Additional land with potential for rainfed crop production

Source: FAO, 2003. BIOFUELS: PROSPECTS, RISKS AND OPPORTUNITIES 61

increased biofuel production on existing and the economically feasible area would be cropland could also trigger expansion in the expected to change with increased demand production of non-biofuel crops elsewhere. for biofuels and their feedstocks (Nelson and For example, increased maize production Robertson, 2008). For example, 23 million for ethanol in the central United States of hectares were withdrawn from crop America has displaced soybean on some (primarily ) production in countries existing cropland, which, in turn, may induce such as Kazakhstan, the Russian Federation increased soybean production and conversion and following the break-up of the of grassland or forest land elsewhere. Thus, former Union of Soviet Socialist Republics; both the direct and indirect land-use changes of these, an estimated 13 million hectares caused by expanded biofuel production need could be returned to production without to be considered for a full understanding of major environmental cost if cereal prices potential environmental impacts. and profit margins remain high and the In 2004, an estimated 14 million hectares, necessary investments in handling, storage worldwide, were being used to produce and transportation infrastructure are made biofuels and their by-products, representing (FAO, 2008e). about 1 percent of global cropland (IEA, The sugar-cane area in Brazil is expected 2006, p. 413).11 Sugar cane is currently to almost double to 10 million hectares over cultivated on 5.6 million hectares in Brazil, the next decade; along with expansion in the and 54 percent of the crop (about 3 million Brazilian soybean area, this could displace hectares) is used to produce ethanol (Naylor livestock pastures and other crops, indirectly et al., 2007). United States farmers harvested increasing pressure on uncultivated land 30 million hectares of maize in 2004, of which (Naylor et al., 2007). China is “committed 11 percent (about 3.3 million hectares) was to preventing the return to used for ethanol (Searchinger et al., 2008). production” of land enrolled in its -for- In 2007, area planted to maize in the United Green programme, but this could increase States of America increased by 19 percent pressure on resources in other countries, (Naylor et al., 2007; see also Westcott, 2007, such as and the Lao People’s p. 8). While the United States soybean area Democratic Republic (Naylor et al., 2007). has declined by 15 percent; Brazil’s soybean The potential significance of indirect area is expected to increase by 6–7 percent to biofuel-induced land-use change is illustrated 43 million hectares (FAO, 2007c). by a recent analysis by Searchinger et al. As noted in Chapter 4, land used for the (2008). They project that maize area devoted production of biofuels and their by-products to ethanol production in the United States is projected by the IEA to expand three- to of America could increase to 12.8 million four-fold at the global level, depending on hectares or more by 2016, depending on policies pursued, over the next few decades, policy and market conditions. Associated and even more rapidly in Europe and North reductions in the area devoted to soybean, America. OECD–FAO (2008) projections wheat and other crops would raise prices suggest that this land will come from a and induce increased production in other global shift towards cereals over the next countries. This could lead to an estimated decade. The additional land needed will 10.8 million hectares of additional land being come from non-cereal croplands in Australia, brought into cultivation worldwide, including Canada and the United States of America; cropland expansions of 2.8 million hectares set-aside lands in the EU or the United States in Brazil (mostly in soybean) and 2.2 million Conservation Reserve Program; and new, hectares in China and India (mostly in maize currently uncultivated land, especially in and wheat). If projected cropland expansion Latin America. Some land that may not have follows the patterns observed in the 1990s, been cultivated profitably in the past may it would come primarily from forest land become profitable as commodity prices rise, in Europe, Latin America, Southeast Asia and sub-Saharan Africa, and primarily from grasslands elsewhere. Critical to this scenario 11 Most first-generation biofuel feedstocks (e.g. maize, is the assumption that price increases will not sugar cane, rapeseed and palm oil) cannot be distinguished by end-use at the crop production stage, so biofuel accelerate yield growth, at least in the short feedstock area is inferred from biofuel production data. term. 62 THE STATE OF FOOD AND AGRICULTURE 2008

Other studies also highlight the possible rainforest. Banse et al. (2008) also foresee indirect land-use changes resulting from significant increases in agricultural land use, biofuel policies (Birur, Hertel and Tyner, particularly in Africa and Latin America, 2007). Meeting current biofuel mandates arising from implementation of mandatory and targets in the EU and the United States biofuel-blending policies in Canada, the EU, of America would significantly increase the Japan, South Africa and the United States of share of domestic feedstock production America. going to biofuels while reducing commodity exports and increasing demand for imports. Intensification Effects would include an expansion in While area expansion for biofuel feedstock land area devoted to coarse in production is likely to play a significant role Canada and the United States of America in satisfying increased demand for biofuels of 11–12 percent by 2010 and in the area over the next few years, the intensification devoted to oilseeds in Brazil, Canada and of land use through improved technologies the EU of 12–21 percent. Brazilian land and management practices will have to prices are estimated to double as a result complement this option, especially if of increased demand for grains, oilseeds production is to be sustained in the long and sugar cane, suggesting that EU and term. Crop yield increases have historically United States biofuel mandates could place been more significant in densely populated considerable pressure on ecosystems in other Asia than in sub-Saharan Africa and Latin parts of the world, such as the Amazon America and more so for and wheat

FIGURE 25 Potential for yield increase for selected biofuel feedstock crops

MAIZE SUGAR CANE

Yield (tonnes/ha) Yield (tonnes/ha) 10 100

8 80

6 60

4 40

2 20

0 0 United China Brazil Mexico India Mexico Brazil India China States of America RAPESEED OIL PALM

Yield (tonnes/ha) Yield (tonnes/ha) 3.5 6

3.0 5 2.5 4 2.0 3 1.5 2 1.0 0.5 1 0.0 0 Germany United France China Canada India China Malaysia Colombia Indonesia Thailand Kingdom

Current yield Potential yield

Note: In some countries, current yields exceed potential yields as a result of , Source: FAO. multiple cropping, input use and various applied production practices. BIOFUELS: PROSPECTS, RISKS AND OPPORTUNITIES 63

than for maize. Large-scale public and lignocellulosic feedstock, this competition private investment in research on improving could be reduced by the higher yields genetic materials, input and water use and that could be realized using these newer agronomic practices have played a critical technologies. role in achieving these yield gains (Hazell and Wood, 2008; Cassman et al., 2005). Despite significant gains in crop yields at How will biofuel production affect the global level and in most regions, yields water, soils and biodiversity? have lagged in sub-Saharan Africa. Actual yields are still below their potential in most The intensification of agricultural production regions – as shown by Figure 25 – suggesting systems for biofuel feedstocks and the that considerable scope remains for increased conversion of existing and new croplands production on existing cropland. Evenson will have environmental effects beyond and Gollin (2003) documented a significant their impacts on greenhouse gas emissions. lag in the adoption of modern high-yielding The nature and extent of these impacts crop varieties, particularly in Africa. Africa are dependent on factors such as scale of has also failed to keep pace with the use of production, type of feedstock, cultivation other yield-enhancing technologies such as and land-management practices, location integrated nutrient and management, and downstream processing routes. Evidence irrigation and conservation tillage. remains limited on the impacts specifically Just as increased demand for biofuels associated with intensified biofuel induces direct and indirect changes in production, although most of the problems land use, it can also be expected to trigger are similar to those already associated changes in yields, both directly in the with agricultural production – water production of biofuel feedstocks and depletion and pollution, soil degradation, indirectly in the production of other crops – nutrient depletion and the loss of wild and provided that appropriate investments are agricultural biodiversity. made to improve infrastructure, technology and access to information, knowledge and Impacts on water resources markets. A number of analytical studies Water, rather than land, scarcity may prove are beginning to assess the changes in land to be the key limiting factor for biofuel use to be expected from increased biofuel feedstock production in many contexts. demand, but little empirical evidence is yet About 70 percent of freshwater withdrawn available on which to base predictions on worldwide is used for agricultural purposes how yields will be affected – either directly or (Comprehensive Assessment of Water indirectly – or how quickly. In one example, Management in Agriculture, 2007). Water ethanol experts in Brazil believe that, even resources for agriculture are becoming without genetic improvements in sugar cane, increasingly scarce in many countries as yield increases in the range of 20 percent a result of increased competition with could be achieved over the next ten years domestic or industrial uses. Moreover, the simply through improved management in expected impacts of climate change in terms the production chain (Squizato, 2008). of reduced rainfall and runoff in some key Some of the crops currently used as producer regions (including the Near East, feedstocks in liquid biofuel production North Africa and South Asia) will place require high-quality agricultural land and further pressure on already scarce resources. major inputs in terms of fertilizer, pesticides Biofuels currently account for about and water to generate economically 100 km3 (or 1 percent) of all water transpired viable yields. The degree of competition by crops worldwide, and about 44 km3 (or for resources between energy crops and 2 percent) of all irrigation water withdrawals food and production will depend, (de Fraiture, Giordano and Yongsong, 2007). among other factors, on progress in crop Many of the crops currently used for biofuel yields, efficiency of livestock feeds and production – such as sugar cane, oil palm biofuel conversion technologies. With and maize – have relatively high water second-generation technologies based on requirements at commercial yield levels (see 64 THE STATE OF FOOD AND AGRICULTURE 2008

Table 10) and are therefore best suited to of water resources in South Asia and East high-rainfall tropical areas, unless they can and Southeast Asia, there is very little land be irrigated. (Rainfed production of biofuel available for extra irrigated agriculture. feedstocks is significant in Brazil, where Most potential for expansion is limited 76 percent of sugar-cane production is under to Latin America and sub-Saharan Africa. rainfed conditions, and in the United States However, in the latter region it is expected of America, where 70 percent of maize that the current low levels of irrigation water production is rainfed.) Even perennial withdrawals will increase only slowly. such as jatropha and pongamia that can be Producing more biofuel crops will affect grown in semi-arid areas on marginal or water quality as well as quantity. Converting degraded lands may require some irrigation pastures or woodlands into maize fields, during hot and dry summers. Further, the for example, may exacerbate problems processing of feedstocks into biofuels can use such as soil erosion, sedimentation and large quantities of water, mainly for washing excess nutrient (nitrogen and phosphorous) plants and seeds and for evaporative cooling. runoff into surface waters, and infiltration However, it is irrigated production of these into groundwater from increased fertilizer key biofuel feedstocks that will have the application. Excess nitrogen in the Mississippi greatest impact on local water resource river system is a major cause of the - balances. Many irrigated sugar-producing starved “dead zone” in the Gulf of Mexico, regions in southern and eastern Africa and where many forms of marine life cannot northeastern Brazil are already operating survive. Runge and Senauer (2007) argue that near the hydrological limits of their as maize–soybean rotations are displaced associated river basins. The Awash, , by maize cropped continuously for ethanol Maputo, Nile and São Francisco river basins production in the United States of America, are cases in point. major increases in nitrogen fertilizer While the potential for expansion of application and runoff will aggravate these irrigated areas may appear high in some areas problems. on the basis of water resources and land, the Biodiesel and ethanol production results actual scope for increased biofuel production in organically contaminated wastewater under irrigated conditions on existing or new that, if released untreated, could increase irrigated lands is limited by infrastructural eutrophication of surface waterbodies. requirements to guarantee water deliveries However, existing wastewater treatment and by land-tenure systems that may not technologies can deal effectively with conform with commercialized production organic pollutants and wastes. systems. Equally, expansion may be systems can reduce the biological oxygen constrained by higher marginal costs of water demand of wastewater by more than storage (the most economic sites have already 90 percent, so that water can be reused for been taken) and land acquisition. Figure 26 processing, and methane can be captured shows that the potential for growth for the in the treatment system and used for power Near East and North Africa region is reaching generation. As regards the distribution its limit. While there remains an abundance and storage phases of the cycle, because TABLE 10 Water requirements for biofuel crops

Annual obtainable Energy Evapotranspiration Potential crop Rainfed crop Irrigated crop CROP fuel yield yield equivalent evapotranspiration evapotranspiration water requirement

(Litres/ha) (GJ/ha) (Litres/litre fuel) (mm/ha) (mm/ha) (mm/ha)1 (Litres/litre fuel)

Sugar cane 6 000 120 2 000 1 400 1 000 800 1 333

Maize 3 500 70 1 357 550 400 300 857

Oil palm 5 500 193 2 364 1 500 1 300 0 0

Rapeseed 1 200 42 3 333 500 400 0 0

1 On the assumption of 50 percent irrigation efficiency. Source: FAO. BIOFUELS: PROSPECTS, RISKS AND OPPORTUNITIES 65

ethanol and biodiesel are biodegradable, on water quality (Hill et al., 2006; Tilman, the potential for negative impacts on soil Hill and Lehman, 2006). and water from leakage and spills is reduced compared with that of fossil fuels. Impacts on soil resources In Brazil, where sugar cane for ethanol is Both land-use change and intensification grown primarily under rainfed conditions, of agricultural production on existing water availability is not a constraint, croplands can have significant adverse but water pollution associated with the impacts on soils, but these impacts – just as application of fertilizers and agrochemicals, for any crop – depend critically on farming soil erosion, sugar-cane washing and other techniques. Inappropriate cultivation steps in the ethanol production process practices can reduce soil are major concerns (Moreira, 2007). Most and increase soil erosion by removing milling wastewater (vinasse) is used for permanent soil cover. The removal of irrigation and fertilization of the sugar- residues can reduce soil nutrient contents cane plantations, thus reducing both water and increase greenhouse gas emissions demands and eutrophication risks. through losses of soil carbon. Pesticides and other chemicals can wash On the other hand, conservation into waterbodies, negatively affecting tillage, crop rotations and other improved water quality. Maize, and other management practices can, under the biofuel feedstocks differ markedly in their right conditions, reduce adverse impacts fertilizer and requirements. Of or even improve environmental quality in the principal feedstocks, maize is subject conjunction with increased biofuel feedstock to the highest application rates of both production. Growing perennials such as fertilizer and pesticides per hectare. Per unit palm, short-rotation coppice, sugar cane of energy gained, biofuels from soybean or switchgrass instead of annual crops can and other low-input, high-diversity improve soil quality by increasing soil cover biomass are estimated to require only and organic carbon levels. In combination a fraction of the nitrogen, with no-tillage and reduced fertilizer and pesticides required by maize, and pesticide inputs, positive impacts on with correspondingly lower impacts biodiversity can be obtained.

FIGURE 26 Potential for irrigated area expansion

Million ha 160

140

120

100 80

60

40

20

0 South Asia East and Latin America Near East Sub-Saharan Southeast and the and Africa Asia Caribbean North Africa

Irrigated area, 2001 Area suitable for irrigation

Source: FAO. 66 THE STATE OF FOOD AND AGRICULTURE 2008

Different feedstocks vary in terms of material and can also lead to reduced use their soil impacts, nutrient demand and the of traditional varieties. extent of land preparation they require. The The first pathway for biodiversity loss IEA (2006, p. 393) notes that the impact of is habitat loss following land conversion sugar cane on soils is generally less than that for crop production, for example from of rapeseed, maize and other cereals. Soil forest or grassland. As the CBD (2008) quality is maintained by nutrients notes, many current biofuel crops are well from sugar-mill and distillery wastes, but suited for tropical areas. This increases the using more as an energy input to economic incentives in countries with biofuel ethanol production would reduce recycling. production potential to convert natural Extensive production systems require re-use ecosystems into feedstock plantations (e.g. of residues to recycle nutrients and maintain oil palm), causing a loss of wild biodiversity soil fertility; typically only 25–33 percent of in these areas. While oil palm plantations do available crop residues from grasses or maize not need much fertilizer or pesticide, even on can be harvested sustainably (Doornbosch poor soils, their expansion can lead to loss of and Steenblik, 2007, p. 15, citing Wilhelm rainforests. Although loss of natural habitats et al., 2007). By creating a market for through land conversion for biofuel feedstock agricultural residues, increased demand production has been reported in some for energy could, if not properly managed, countries (Curran et al., 2004; Soyka, Palmer divert residues to the production of biofuels, and Engel, 2007), the data and analysis with potentially detrimental effects on soil needed to assess its extent and consequences quality, especially on soil organic matter are still lacking. Nelson and Robertson (2008) (Fresco, 2007). examined how rising commodity prices Hill et al. (2006) found that the production caused by increased biofuel demand could of soybean for biodiesel in the United States induce land-use change and intensification in of America requires much less fertilizer Brazil, and found that and pesticide per unit of energy produced driven by higher prices could endanger areas than does maize. But they argue that both rich in bird diversity. feedstocks require higher input levels and The second major pathway is loss of better-quality land than would second- agrobiodiversity, induced by intensification generation feedstocks such as switchgrass, on croplands, in the form of crop genetic woody plants or diverse mixtures of prairie uniformity. Most biofuel feedstock grasses and forbs (see also Tilman, Hill and plantations are based on a single species. Lehman, 2006). Perennial lignocellulosic There are also concerns about low levels crops such as , poplar, or of in grasses used as grasses require less-intensive management feedstocks, such as sugar cane (The and fewer fossil-energy inputs and can also Royal Society, 2008), which increases the be grown on poor-quality land, while soil susceptibility of these crops to new pests and carbon and quality will also tend to increase diseases. Conversely, the reverse is true for over time (IEA, 2006). a crop such as jatropha, which possesses an extremely high degree of genetic diversity, Impacts on biodiversity most of which is unimproved, resulting in a Biofuel production can affect wild and broad range of genetic characteristics that agricultural biodiversity in some positive undermine its commercial value (IFAD/FAO/ ways, such as through the restoration of UNF, 2008). degraded lands, but many of its impacts With respect to second-generation will be negative, for example when natural feedstocks, some of the promoted species landscapes are converted into energy- are classified as , raising new crop plantations or peat lands are drained concerns over how to manage them and (CBD, 2008). In general, wild biodiversity is avoid unintended consequences. Moreover, threatened by loss of habitat when the area many of the enzymes needed for their under crop production is expanded, whereas conversion are genetically modified to agricultural biodiversity is vulnerable in increase their efficiency and would need to the case of large-scale monocropping, be carefully managed within closed industrial which is based on a narrow pool of genetic production processes (CFC, 2007). BIOFUELS: PROSPECTS, RISKS AND OPPORTUNITIES 67

Positive effects on biodiversity have the introduction of biofuel production on been noted in degraded or marginal areas marginal lands depends critically on the where new perennial mixed species have nature and security of their rights to land. been introduced to restore ecosystem It is not unusual to hear claims that functioning and increase biodiversity significant tracts of marginal land exist that (CBD, 2008). Experimental data from test could be dedicated to biofuel production, plots on degraded and abandoned soils thus reducing the conflict with food crops (Tilman, Hill and Lehman, 2006) show and offering a new source of income to poor that low-input high-diversity mixtures of farmers. Although such lands would be less native grassland perennials – which offer productive and subject to higher risks, using a range of ecosystem services, including them for bioenergy plantations could have wildlife habitat, water filtration and carbon secondary benefits, such as restoration of sequestration – also produce higher net degraded vegetation, carbon sequestration energy gains (measured as energy released and local environmental services. In most on ), greater greenhouse gas countries, however, the suitability of this emission reductions and less agrichemical land for production is pollution than do maize-ethanol or poorly documented. soybean-biodiesel and that performance Growing any crop on marginal land increases with the number of species. with low levels of water and nutrient The authors of this study also found that inputs will result in lower yields. - switchgrass can be highly productive on tolerant jatropha and sweet are fertile soils, especially when fertilizer no exception. To produce commercially and pesticides are applied, but that its acceptable yield levels, plant and tree species performance on poor soils does not match cannot be stressed beyond certain limits; in that of diverse native perennials. fact, they will benefit from modest levels of additional inputs. Thus, while improved crops may offer potential over the longer term, Can biofuels be produced on adequate nutrients, water and management marginal lands? are still needed to ensure economically meaningful yields – implying that even hardy Marginal or degraded lands are often crops grown on marginal lands will still characterized by lack of water, which compete to some extent with food crops for constrains both plant growth and nutrient resources such as nutrients and water. availability, and by low soil fertility and Numerous studies confirm that the value high temperatures. Common problems in of the higher economic yields from good these areas include vegetation degradation, agricultural land usually outweighs any water and wind erosion, salinization, additional costs. Thus, there is a strong soil compaction and crusting, and soil- likelihood that sustained demand for nutrient depletion. Pollution, acidification, biofuels would intensify the pressure on the alkalization and waterlogging may also occur good lands where higher returns could be in some locations. realized (Azar and Larson, 2000). Biofuel crops that can tolerate environmental conditions where food crops might fail may offer the opportunity to Ensuring environmentally put to productive use land that presently sustainable biofuel production yields few economic benefits. Crops such as cassava, castor, , Good practices jatropha and pongamia are potential Good practices aim to apply available candidates, as are tree crops that tolerate knowledge to address the dry conditions, such as eucalyptus. It is dimensions of on- biofuel feedstock important to note, however, that marginal production, harvesting and processing. lands often provide subsistence services to This aim applies to natural-resource the rural poor, including many agricultural management issues such as land, soil, water activities performed by women. Whether and biodiversity as well as to the life-cycle the poor stand to benefit or suffer from analysis used to estimate greenhouse gas 68 THE STATE OF FOOD AND AGRICULTURE 2008

BOX 11 Jatropha – a “miracle” crop?

As an , (L.) production as well as small-scale rural (jatropha) is making a lot of headlines. development. International and national The plant is drought-tolerant, grows well investors are rushing to establish large on marginal land, needs only moderate areas for jatropha cultivation in , rainfall of between 300 and 1 000 mm per Brazil, China, , , the Gambia, year, is easy to establish, can help reclaim , India, Indonesia, Mozambique, eroded land and grows quickly. These Myanmar, the , and the characteristics appeal to many developing United Republic of . The largest- countries that are concerned about scale venture is the Indian Government’s diminishing tree cover and soil fertility “National Mission” to cultivate jatropha and are looking for an energy crop that on 400 000 hectares within the period minimizes competition with food crops. 2003–07 (Gonsalves, 2006). By 2011–12, At the same time, this small tree produces the goal is to replace 20 percent of diesel seeds after two to five years containing consumption with biodiesel produced 30 percent oil by kernel weight – oil that is from jatropha, cultivated on around already being used to make soap, candles 10 million hectares of wasteland and and cosmetics and has similar medicinal generating year-round employment for properties to castor oil, but is also useful 5 million people (Gonsalves, 2006; Francis, for and electricity generation. Edinger and Becker, 2005). The original A native of northern Latin/Central target may well be ambitious, as Euler and America, there are three varieties Gorriz (2004) report that probably only of jatropha: Nicaraguan, Mexican a fraction of the initial 400 000 hectares (distinguished by its less- or non-toxic allocated to jatropha by the Indian ) and Cape Verde. The third of these Government is actually under cultivation. varieties became established in Cape Verde The plant also grows widely in Africa, and from there spread to parts of Africa often as separating properties in and Asia. On Cape Verde it was grown on towns and villages. In , thousands a large scale for export to for oil of kilometres of jatropha hedges can be extraction and soap-making. At its peak, found; they protect from livestock in 1910, jatropha exports reached over and can also help reduce damage and 5 600 tonnes (Heller, 1996). erosion from wind and water. The seed The many positive attributes claimed for is already used for soap-making and jatropha have translated into numerous medicinal purposes, and jatropha oil projects for large-scale oil and/or biodiesel is now also being promoted by a non-

emissions and determine whether a specific crop rotations. In the context of the current biofuel is more climate-change friendly than focus on carbon storage and on technologies a fossil fuel. In practical terms, soil, water that reduce energy intensity it seems and crop protection; energy and water especially appropriate. The approach also management; nutrient and agrochemical proves responsive to situations where labour management; biodiversity and landscape is scarce and there is a need to conserve soil conservation; harvesting, processing and moisture and fertility. Interventions such distribution all count among the areas as mechanical soil tillage are reduced to a where good practices are needed to address minimum, and inputs such as agrochemicals sustainable bioenergy development. and nutrients of or organic origin are Conservation agriculture is one practice that applied at an optimum level and in amounts sets out to achieve sustainable and profitable that do not disrupt biological processes. agriculture for farmers and rural people Conservation agriculture has been shown to by employing minimum soil disturbance, be effective across a variety of agro-ecological permanent organic soil cover and diversified zones and farming systems. BIOFUELS: PROSPECTS, RISKS AND OPPORTUNITIES 69

governmental organization to power soil reclamation and erosion control, multifunctional platforms, a slow-speed and be used for living fences, firewood, diesel containing an oil expeller, a green , lighting fuel, local soap generator, a small battery charger and a production, and medicinal grinding mill (UNDP, 2004). Pilot projects applications. However, they conclude that promoting jatropha oil as an energy claims of high oil yields in combination source for small-scale rural electrification with low nutrient requirements (soil projects are under way in the United fertility), lower water use, low labour Republic of Tanzania and other African inputs, the non-existence of competition countries. with food production and tolerance Despite considerable investment and to pests and diseases are unsupported projects being undertaken in many by scientific evidence. The most critical countries, reliable scientific data on the gaps are the lack of improved varieties of jatropha are not available. and available seed. Jatropha has not yet Information on the relationship between been domesticated as a crop with reliable yields and variables such as soil, climate, performance. crop management and crop genetic The fear that the rush into jatropha material on which to base investment on the basis of unrealistic expectations decisions is poorly documented. What will not only lead to financial losses but evidence there is shows a wide range of also undermine confidence among local yields that cannot be linked to relevant communities – a recurrent theme in many parameters such as soil fertility and water African countries – appears to be well availability (Jongschaap et al., 2007). founded. Sustainable jatropha plantations Experience with jatropha plantations in will mean taking the uncertainty out the 1990s, such as the “Proyecto Tempate” of production and marketing. Further in , which ran from 1991 to research is needed on suitable germplasm 1999, ended in failure (Euler and Gorriz, and on yields under different conditions, 2004). and markets need to be established to Indeed, it appears that the many promote sustainable development of positive claims for the plant are not the crop. based on mature project experiences. Jongschaap et al. (2007) argue that, on a modest scale, jatropha cultivation can help with soil-,

Good farming practices coupled with the question remains of how they can best good forestry practices could greatly reduce be assessed and reflected in field activities. the environmental costs associated with Existing environmental impact-assessment the possible promotion of sustainable techniques and strategic environmental intensification at forest margins. Approaches assessments offer a good starting point for based on agro-silvo-pasture-livestock analysing the biophysical factors. There integration could be considered also when also exists a wealth of technical knowledge bioenergy crops form part of the mix. drawn from agricultural development during the past 60 years. New contributions from Standards, sustainability criteria and the bioenergy context include analytical compliance frameworks for bioenergy and Although the multiple and diverse and for bioenergy impact analysis (FAO, environmental impacts of bioenergy forthcoming (a) and (b)); work on the development do not differ substantively aggregate environmental impacts, including from those of other forms of agriculture, soil acidification, excessive fertilizer use, 70 THE STATE OF FOOD AND AGRICULTURE 2008

biodiversity loss, and pesticide establishment of such a system and are the (Zah et al., 2007); and work on risks sufficiently great that its absence would social and environmental sustainability pose significant, irreversible threats to criteria, including limits on deforestation, human health or the environment? Should competition with food production, adverse biofuels be treated more stringently than impacts on biodiversity, soil erosion and other agricultural commodities? nutrient leaching (Faaij, 2007). On the one hand, given that most The biofuel sector is characterized environmental impacts of biofuels are by a wide range of stakeholders with indistinguishable from those of increased diverse interests. This, combined with agricultural production in general, it could the rapid evolution of the sector, has led be argued that equal standards should be to a proliferation of initiatives to ensure applied across the board. Furthermore, sustainable bioenergy development. restricting land-use change could foreclose Principles, criteria and requirements are opportunities for developing countries under consideration among many private to benefit from increased demand for and public groups, along with compliance agricultural commodities. On the other mechanisms to assess performance and hand, there are also strong arguments that guide development of the sector. The agricultural producers and policy-makers Global Bioenergy Partnership’s task forces should learn from earlier mistakes and on greenhouse gas methodologies and avoid the negative environmental impacts on sustainability, and the round table on that have accompanied agricultural land sustainable biofuels, count among these, conversion and intensification in the past. together with many other public, private Solutions to this dilemma will require and non-profit efforts. Such diversity careful dialogue and negotiation among suggests that a process for harmonizing countries if the combined goals of the various approaches may be needed, agricultural productivity growth and especially in the light of policy mandates environmental sustainability are to be and targets that serve to stimulate further achieved. A starting point might be biofuel production. found by establishing best practices for Most of the criteria are currently being sustainable production of biofuels, which developed in industrialized countries can then also help transform farming and are aimed at ensuring that biofuels practices for non-biofuel crops. In time, are produced, distributed and used in an and accompanied by capacity-building environmentally sustainable manner before efforts for the countries that need it, they are traded in international markets. more stringent standards and certification The European Commission, for example, systems could be established. has already proposed criteria that it One option to explore could be considers to be compatible with WTO rules payments for environmental services in (personal communication, E. Deurwaarder, combination with biofuel production. European Commission, 2008). However, Payments for environmental services were to date none have yet been tested, discussed in detail in the 2007 edition of especially in conjunction with government The State of Food and Agriculture. This support schemes such as subsidies or when mechanism would compensate farmers designated for preferential treatment under for providing specific environmental international trade agreements (Doornbosch services using production methods that are and Steenblik, 2007; UNCTAD, 2008). environmentally more sustainable. Payments The term “standards” implies rigorous could be linked to compliance with systems for measuring parameters against standards and certification schemes agreed defined criteria, in which failure to comply at the international level. Payment schemes would prevent a country from exporting its for environmental services, although product. Such internationally agreed systems challenging and complicated to implement, already exist for a range of food safety, could constitute a further tool to ensure chemical and human health topics. Is the that biofuels are produced in a sustainable biofuel sector sufficiently developed for the manner. BIOFUELS: PROSPECTS, RISKS AND OPPORTUNITIES 71

annual crops with perennial feedstocks Key messages of the chapter (such as oil palm, jatropha or perennial grasses) can improve soil carbon • Biofuels are only one component of balances, but converting tropical forests a range of alternatives for mitigating for crop production of any kind can greenhouse gas emissions. Depending release quantities of greenhouse gases on the policy objectives, other options that far exceed potential annual savings may prove more cost-effective, from biofuels. including different forms of renewable • Availability of water resources, limited energy, increased energy efficiency by technical and institutional factors, and conservation, and reduced will constrain the amount of biofuel emissions from deforestation and land feedstock production in countries that degradation. would otherwise have a comparative • Notwithstanding that the impacts advantage in their production. of increased biofuel production on • Regulatory approaches to standards greenhouse gas emissions, land, and certification may not be the first or water and biodiversity vary widely best option for ensuring broad-based across countries, biofuels, feedstocks and equitable participation in biofuel and production practices, there is production. Systems that incorporate a strong and immediate need for best practices and capacity building harmonized approaches to life-cycle may yield better short-term results and analysis, greenhouse gas balances and provide the flexibility needed to adapt sustainability criteria. to changing circumstances. Payments • Greenhouse gas balances are not positive for environmental services may also for all feedstocks. For climate-change represent an instrument for encouraging purposes, investment should be directed compliance with sustainable production towards crops that have the highest methods. positive greenhouse gas balances with • Biofuel feedstocks and other food and the lowest environmental and social agricultural crops should be treated costs. similarly. The environmental concerns • Environmental impacts can be generated over biofuel feedstock production at all stages of biofuel feedstock are the same as for the impacts of production and processing, but processes increased agricultural production related to land-use change and in general; therefore measures to intensification tend to dominate. Over ensure sustainability should be applied the next decade, rapid policy-driven consistently to all crops. growth in demand for biofuels is likely • Good agricultural practices, such as to accelerate the conversion of non- conservation agriculture, can reduce agricultural lands to crop production. the and the adverse This will occur directly for biofuel environmental impacts of biofuel feedstock production and indirectly production – just as they can for for other crops displaced from existing extensive agricultural production in cropland. general. Perennial feedstock crops, • Yield increases and careful use of such as grasses or trees, can diversify inputs will be essential components production systems and help improve in alleviating land-use pressure from marginal or degraded land. both food and energy crops. Dedicated • Domestic government policy must research, investment in technology become better informed of the and strengthened institutions and international consequences of biofuel infrastructure will be required. development. International dialogue, • Environmental impacts vary widely across often through existing mechanisms, feedstocks, production practices and can help formulate realistic and locations, and depend critically on how achievable biofuel mandates and land-use change is managed. Replacing targets.

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