Ask the Experts: the Food Versus Fuel Debate

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Biofuels (2012) 3(6), 635–648

The food versus fuel debate

The food versus fuel debate is arguably one of the most hotly discussed topics in bioenergy research. Biofuels has invited a panel of international experts, covering a wide range of expertise – from policy and economics to advanced feedstocks and technological advances – to express their views on the debate. The experts speak to Ruth Williamson, Commissioning Editor, as they speculate on the current status and future prospects of the evolving debate.

Tom Richard, Penn State University, USA; [email protected] Expert in agroecosystem modeling and biomass supply chains

QQ As an expert in land-based feedstock development, what would you regard as the major advances in this field to date? In sharp contrast to food crops, which people have been growing and breeding for millen- nia, research on most energy crops is still in its infancy. Yet even in a relatively short period of time, we have seen breeding programs increase yields of energy crops such as switchgrass and willow by 30–50% [1,2] . We are just beginning to see results from the application of crop biotechnology to dedicated energy crops, but initial indications are promising. Of particular importance are increased tolerance to stress (e.g., water, nutrients and pests), control of invasiveness (through sterile lines and delayed flowering) and enhanced energy characteristics (e.g., by modifying cell wall constituents such as cellulose, hemicellulose and lignin). Along with these advances in genetics and agronomic practices, there have also been considerable advances in the use of remote sensing, environmental data and crop production models to allow more accurate prediction of food and biofuel crop production and potential. Foley’s group has used these tools to demonstrate the huge potential to increase yields by more effective use of current agricultural technologies for both food [3] and biofuels [4]. These and many other studies demonstrate that agricultural intensification can provide much more food and fuel from existing agricultural land, and in the process free up additional land for biofuel production. When we combine the biofuel feedstock potential of new genetic improvements and agricultural intensification, the potential for large-scale biofuel production is enormous [5].

QQ How has the competition for land differed between developed and developing countries? One of the least understood features of agricultural economies in the developed world is the fundamental depen- dence on continuously increasing consumption. In the last few decades, over 100 million ha of agricultural land in Europe and North America has been abandoned, largely due to lack of demand. Over the coming decades, as populations stabilize and diets continue to shift to more poultry and away from land-intensive beef, the land required to feed the developed world will decrease even without increases in crop yield. But yields do increase, by 2–3% annually, and this further reduces the land required. For most of the last century, US agricultural policy has primarily focused on managing excess production and the current corn ethanol industry is in many ways a response to that need. However, it is important to recognize that the situation in Europe and North America is still somewhat unique, and the conflict between food and fuel remains a feature of biofuel development in many other parts of the world. Of particular concern is the land-grabbing phenomena now recognized in Africa, also evident in South America and Asia, where wealthy individuals and multinational corporations take advantage of informal land tenure rela- tionships to secure vast areas for biofuel production, exporting to markets in the developed world. Land-grabbing is also an increasingly common factor in global food production, in part to satisfy demand in the developing world

where population and diet shifts are still requiring increased production of food. Whether the land is appropri- ated for food or fuel, indigenous people are usually living and subsistence farming in these landscapes, with deep historical and cultural ties. Taking land and livelihoods away from people in such circumstances can be a violation of basic human rights. We need effective governance systems and market incentives to convince biofuel developers to responsibly address the human as well as the environmental dimensions of large-scale commercialization.

QQ What further challenges remain in scaling up biofuel feedstocks while ensuring direct competition with food crops is reduced? There is increasing evidence that agricultural intensification, more land-efficient diets and better integration of energy crops on existing agricultural land will allow very large-scale production of biofuels without conflicting with food production. But while it may be technically possible to avoid this conflict, successful implementation will require compatible economic, social and cultural systems as well. For example, many parts of the USA currently have conservation programs to encourage switchgrass production on erodible land and cover crops such as winter rye on annual cropland, but the conservation rules often preclude harvesting these crops for bioenergy applications. Financing systems for conventional agriculture are geared toward annual crops, and introducing perennial energy crops requires long-term investments. Similarly, standard mechanisms for risk management, such as crop insurance, are generally not available for energy crops, and shifts in cropping systems will result in different seasonal labor requirements, landscape aesthetics and community dynamics. We need to create balanced incentive programs that support both food and fuel production to achieve the agricultural intensification a sustainable future will require.

We need to create balanced incentive programs that support both food and fuel production to achieve the “ agricultural intensification a sustainable future will require. ” QQ Is there a particular area of research in feedstock development that warrants further development in order to limit such competition? Land that is marginal or has been abandoned from food production is often targeted for perennial energy crops, but crop varieties and production practices need to be optimized for these less-productive landscapes. Most of our conventional crop breeding programs are situated on prime agricultural land, as many of the initial biomass feedstock trials have been. It is only recently that plant breeders have starting focusing on developing feedstock varieties that are adapted to the low nutrient, dry or waterlogged conditions common on abandoned and marginal landscapes. As we target these nonfood landscapes for energy crop production, we need both adapted varieties and appropriate agronomic practices to achieve commercial success. To maximize these benefits, we also need research on sustainable strategies for land use transitions. In 2008, studies led by Searchinger et al. and Fargione et al. brought the issue of indirect land use change to the forefront of the debate on sustainable biofuels, demonstrating the decades, or sometimes centuries, of carbon debt that can accrue from poorly selected or poorly managed land use transitions [6,7]. Several groups have since published studies that shed additional light on this issue, and some governmental agencies have applied regulatory constraints. However, we have not seen a widespread attempt to minimize the carbon debt associated with biofuels development and land use change. At a very practical level, we need planting and production strategies for perennial crops that retain or enhance soil organic matter, control weeds and minimize nutrient losses, especially on marginal land. Careful site selection, combined with appropriate varieties and agronomic practices, will allow feedstock production in places that minimize conflicts with food.

QQ Do you feel that further advancing land-based feedstocks is the key to ending the food versus fuel debate? The real key to ending this debate is a more widespread understanding that the choice is not between food and fuel, but rather a choice of how agriculture and forestry can provide for the full range of human and planetary needs. Will our diets be land intensive [8] and our food systems waste 40% of what we grow [9], while we continue to burn fossil energy and heat up the planet? Or will we balance our need for healthy nutrition, renewable materials and low-carbon energy – in which case biofuels will need to play an essential role for aviation, shipping and a significant fraction of land transportation? This is the question we really need to answer.

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While there is strong evidence that crop improvements and agricultural intensification can effectively resolve the food–fuel dilemma, if biofuels are to be a sustainable energy resource we must ensure they are produced in sustainable agricultural systems. As we are realizing to our collective dismay this year, high yields of conventional food crops are highly dependent on both productive soils and a favorable climate. Looking forward, we clearly need both food and fuel cropping systems that are more resilient to climate extremes. The introduction of perennial energy crops into our annual food crop systems can make an important contribution in this regard. Perennials can be integrated in agroecosystems in both space and time to enhance system resilience. In space, strategic placement of perennials on steep slopes and streamside buffers can generate more reliable yields in years of drought and flood, and provide corresponding soil erosion and water quality benefits. With respect to time, incorporating perennials in annual crop rotations can improve soil properties such as water and nutrient holding capacity, to the benefit of future food crops in those fields. Integrating energy crops in our conventional food crop systems can thus provide a range of ecosystem services that enhance soil, water and biodiversity. It is important to recognize and incentivize these synergies between food and fuel, so that we create sustainable agricultural systems that better provide all of our needs for generations to come.

Financial & competing interests disclosure T Richard has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Yusuf Chisti, Massey University, New Zealand; [email protected] Expert in the development of nonedible feedstocks for biofuels

QQ Currently, how do nonedible feedstocks compare to edible feedstocks in terms of usage for biofuel production? Production of fuels from algae has been proven possible and is being carried out in multiple pilot-scale evaluation facilities [10,11] . Unfortunately, at the moment, algal fuels are much more expensive compared with fossil fuels; algal fuels are expensive also relative to fuels derived from crops such as soybean and oil palm. As a consequence, algae are not being used as commercial feedstocks for making biofuels. Lignocellulosic biomass is another nonedible feedstock for making liquid biofuels such as bioethanol and biobutanol. Fuel alcohols will eventually be derived from lignocellulosic biomass and agroindustrial waste instead of from corn and sugarcane. This may entirely displace the use of food crops for production of fuel alcohols, but will not necessarily remove competition for the resources needed for growing food. For example, if agricultural crop residues are removed from land for making fuels, the need for fertilizers for agriculture will increase. Similarly, growing dedicated lignocellulosic crops for fuels will require land, water and fertilizers. In the long run, algal fuels may be superior to crop derived bioethanol [12], but commercializing them requires much more effort compared with commercialization of lignocellulosic fuels.

QQ One main advantage of nonedible feedstocks is that they do not compete directly with agricultural land. Therefore, why do we use edible feedstocks at all? At the moment, production of biofuels from nonedible feedstocks such as lignocellulosic biomass, crop residues and algae is actually more expensive than production from edible feedstocks such as corn, soybeans, canola and sugarcane. Advances in technology will likely change this; for example, the cost of producing bioethanol from lignocellulose has continually declined over the years and production from cellulosic biomass is already being evaluated in some quite large pilot facilities. Cheaper methods are being developed to convert cellulose to fermentable sugars and to convert the sugars to bioethanol. Biogas produced by anaerobic digestion of organic waste is already being used to some extent, but is of limited value as a transport fuel. Also, the supply of readily useable organic waste for producing biogas is limited in comparison with the energy consumption of an industrial economy. For example, in the UK, if all the sewage

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sludge, animal waste, farm manure and domestic and commercial food waste is used to produce biogas, less than 3% of the of the annual national fossil energy demand could be met [13] . In short, nonedible feedstocks are either in short supply or too expensive to use for producing fuels because of technical limitations. Increasing the production of land-based nonedible crops as fuel feedstock is not desirable as it does not eliminate competition for the resources needed for food production.

…nonedible feedstocks are either in short supply or too expensive to use for producing fuels “ because of technical limitations. ” QQ What are the main challenges that remain for the commercialization of nonedible feedstocks? Focusing on algae, the cost of oil-rich algal biomass production needs to be reduced quite substantially. This requires increasing the biomass productivity and oil content. Although microalgae are better than land plants in converting sunlight to biochemical energy, the conversion efficiency, or photosynthetic efficiency, needs to be further improved. This will likely happen through genetic and metabolic engineering [14–20] . Questions remain about scalability of production of algal fuels [21] . Suitable land may be available and there

is certainly no shortage of seawater but, paradoxically, the supply of CO2 appears to be a major limitation [21] .

Although much CO2 is released in the atmosphere daily, it gets diluted and cannot be easily captured by algae.

This poses a substantial limitation to large-scale production of algal fuels. Ultimately, CO2 capture from a relatively low concentration in the atmosphere will be necessary for sustainable production of meaningful quantities

of algal fuels. The biological capabilities for capturing CO2 already existing in the algae will need to be greatly improved through genetic and metabolic engineering [22]. Growing algae requires nitrogen and phosphorous fertilizers and it is possible to recycle much of the phospho- rus and some nitrogen. On an equal mass basis, algae generally need much more nitrogen than land plants do. Production of nitrogen fertilizers depends on fossil energy; although the atmosphere has a lot of freely available nitrogen, algae cannot use this. A capability for fixing this nitrogen exists in some microorganisms including in some algae-like cyanobacteria [23]. An ability to fix atmospheric nitrogen may have to be incorporated in the algae, to eliminate the need of providing nitrogen fertilizers at a substantial expense in fossil energy. Production of fuels from marine algae does require some freshwater, although possibly less than would be needed for producing biofuels from land plants. There is a need to develop technologies for minimizing the input of freshwater. The energy efficiency of algal production processes needs to be improved [11,24] .

QQ Do you envisage that, if these challenges are overcome, biofuel production will not compete with agricultural land in the future? If fuels from marine algae can be commercialized, competition for agricultural land for fuels will be mostly eliminated, but competition for some of the other resources needed for agriculture will persist; for example, the competition for fertilizers. This competition may also be largely removed, but doing so will need a substantial and sustained effort over many years; for example, through biological nitrogen fixation.

QQ In your opinion, how do you feel that the food versus fuel debate will evolve over the next 5–10 years? Food and fuel are both essential for existence. Food is fuel for the body and biofuels have been an almost exclusive source of our energy for much of our existence – sustainable production of both food and fuels is vital. At the moment, unfortunately, production of neither food nor biofuels appears to be sustainable [25,26]. This is being increasingly recognized and is spurring in the development of sustainable production methods. With time, fossil fuels will become increasingly expensive and this will affect the cost of producing food and biofuels. Increasing emphasis will be placed on developing sustainable production alternatives. Pressure on elimi- nating competition between the production of food and fuels will mount. Food production will surely win, as it must, and biofuels that compete minimally with food production will become the focus of attention. Fuels from marine algae, crop residues and organic wastes will provide an increasing fraction of the renewable energy in the future. Bioengineered crops with enhanced productivity will play an increasing role in production of both food and biofuels. Other nonbiological sources of renewable energy will be needed to supplement the

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biological sources. Completely novel technologies, particularly biotechnologies, will be needed to make food and fuel production sustainable [26,27]. In short, in the future we will have to give up any biofuel that substantially competes with food production or is associated with deforestation. Food must remain affordable for social sustainability.

Financial & competing interests disclosure Y Chisti has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Chris R Somerville, Energy Biosciences Institute, University of California, Berkeley, USA; [email protected] Expert in production of cellulosic biofuels

QQ The Energy Biosciences Institute has completed leading research into many aspects of the production of lignocellulosic biofuels. How has such research improved the production of biofuel feedstocks? During the past 5 years we have had a strong focus on investigating the use of perennial grasses such as switchgrass and miscanthus as dedicated energy crops. Members of the institute have examined the availability of land for production of energy crops, developed computer models for estimating rain-fed yield across the USA, measured the water use of these crops in different conditions, identified the major pests and pathogens on these species, developed improved practices for planting and harvesting miscanthus, examined invasiveness of some seeded species of miscanthus, obtained a draft genome sequence of miscanthus and developed spatially detailed economic models for production of energy crops, among other things. Additionally, we have initiated field trials of a large number of other species for use as potential energy crops, including several agave species that may be uniquely useful for arid and semi-arid regions. Perhaps the main result from that latter line of research has been the development of some very promising cordgrass lines by DK Lee at the University of Illinois. Altogether we spent approximately US$20 million on these and related research topics during the past 5 years. We believe that the results from this research provides a preliminary basis for understanding many of the issues associated with production of perennial grasses as energy crops. However, much remains to be done. Energy crops are in their infancy compared with conventional field crops and I believe that it will take several decades to begin to understand all of the issues associated with the major energy crops at levels that are similar to conventional crops.

The US Government pays farmers not to farm approximately 32 million acres in the USA so, in principle, “ that land could be available for certain types of energy crops. ” QQ Has research focused on simply improving the efficiency of biofuel feedstocks, or is there a focus on developing feedstocks for land that do not directly compete with food crops? We have had a strong focus on developing energy crops that do not compete with the major food and feed crops. In fact, our economists have informed us that it is very unlikely that energy crops can compete on economic terms with major crops such as corn and soybean, and I think the same is true of wheat, although we have not studied that. It is relatively easy to identify land that is not used for current crops. The US Government pays farmers not to farm approximately 32 million acres in the USA so, in principle, that land could be available for certain types of energy crops. There are approximately 750 million acres of trees in the USA that apparently do not compete with food production (i.e., one does not hear of ‘food versus forests’ in spite of the fact that trees occupy approximately 20-times as much land as the corn acreage used for ethanol). There is a lot of sloping land that is not suitable for annual crops but that could be suitable for perennials, and there is a lot of semi-arid land that is not used for food or feed that could support a lot of biomass production from species such as agaves, because of their very high water use efficiency and drought tolerance.

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QQ What aspect of improving the utility of biofuel feedstocks is key in reducing the competition of feedstocks with food? I think that one key to utilizing land that is not used for current food crop production is to identify the perennial plant species that can thrive on marginal acres. Perennials are particularly important for marginal acres because some types (e.g., trees and agaves) do not need to be harvested every year. By accumulating biomass over several years, the costs of harvesting and transportation can be minimized. ‘Marginal’ can mean many things – sloping, arid or prone to drought, salty, uneven terrain (i.e., too irregular for field cropping), cold, contaminated, prone to flooding and so on. There is no single solution to utilizing marginal land. Because any type of lignocellulose can be used for biofuels production, many of the constraints associated with domestication of food crops are not relevant and so we can draw on the high diversity of the plant kingdom to identify species that can be useful for this application.

QQ What future research in feedstock biology do you feel is required to further reduce the competition with biofuels and food? All the topics listed in the first question concerning development of energy crops seem relevant. Indeed, I think we need to understand energy crops in the same detail as we understand the crops used for food, feed and fiber. Since most prospective energy crops have not been studied to any extent, everything is of interest. In some cases the most pressing needs may not be related to biomass production per se but are enabling technology. For instance, many prospective energy grasses are self-incompatible. I think that it would greatly accelerate breeding of such species if we could identify chemicals that suppress self incompatibility. Similarly, photoperiodic induction of flowering can strongly limit the utility of certain species because they flower early and stop accumulating biomass long before the growing season ends. Being able to manipulate flowering would be very useful and might also have utility in reducing concerns about invasiveness of certain species.

I think it likely that the US corn ethanol industry may actually increase food security by providing a buffer of “ corn that can be repurposed for food production in drought years such as 2012. ” QQ How do you feel this may impact the food versus fuel debate? I think the food versus fuel debate is a surrogate for a much deeper societal problem. As noted above, we do not have a food versus forests debate. I think the real issue is that, because of population growth, we are on a trajectory of diminishing resources per capita. At the same time, the large emerging economies are expanding the competition for all types of resources. The food versus fuel debate is shorthand for the idea that food should be used to feed poor people with a higher priority than supporting wasteful energy practices (e.g., sport utility vehicles). I agree entirely with the sentiment. However, I believe that if the corn ethanol industry were to disappear tomorrow, most of the corn that was produced for ethanol would no longer be grown because the people who need food support cannot afford it and no other entities have been willing to buy it for them. Indeed, I think it likely that the US corn ethanol industry may actually increase food security by providing a buffer of corn that can be repurposed for food production in drought years such as 2012. More generally, I think the consequences of climate change will be much more lasting and devastating to global food security than using some land to produce enough biofuels to reduce GHG emissions from transportation fuels. I do not think that there have been enough studies of the tradeoffs in human welfare of using some land to reduce GHG emissions versus other potential uses such as ecosystem services or food security. My own motivations for studying cellulosic biofuels are rooted in the belief that minimizing climate change is the single most important thing we can do to preserve natural ecosystems and maximize food security.

Financial & competing interests disclosure CR Somerville’s research is supported by the energy company BP plc. CR Somerville was also a cofounder of Mendel Biotechnology and LS9 Inc., and owns shares in both companies. All these companies have business interests in the area of advanced biofuels. CR Somerville has no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

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Harvey Blanch, Joint BioEnergy Institute, University of California Berkeley, USA; [email protected] Expert in advanced bioprocessing of biomass for biofuels

QQ How have bioprocessing techniques improved over recent years in order to advanced land-based feedstocks? There has been a resurgence of interest in the use of lignocellulosic biomass (both grasses and woody biomass) as alternatives to starch-based crops for fuel production. Cellulosic ethanol would use less water and require less land than ethanol produced from corn. The development of cost-effective processes using lignocellulosic feedstocks will do much to alleviate concerns about land use competition between food/feed and fuels. Arguably, biomass pretreatment is the most critical step in lignocellulose conversion to fuels. Effective pretreatment can enable access to all of the saccharides present in biomass and, thus, increase fuel yields from biomass. There has been steady, incremental improvement in a number of well-studied pretreatment methods (e.g., dilute acid, organosolv and alkaline treatment). Newer methods, such as liquid ammonia percolation, show very effective release of sugars by enzymatic saccharification. Biomass solubilization in certain ionic liquids (ILs), with precipita- tion of cellulose by antisolvent addition, provides a readily saccharified, decrystallized cellulose stream. This IL pretreatment method also provides a soluble lignin stream that could be converted to fuel or other products. The challenge here is to reduce the cost of the ILs and recycle them in the process. If successful, this could result in an entirely new pretreatment approach. Lignin remains as a largely untapped source of carbon and a significant research challenge. Bioprocessing and metabolic engineering advances in the conversion of the hemicellulose monomers in ligno cellulosic biomass to ethanol and fungible fuels now enable even higher fuel yields to be obtained from biomass. In contrast, starch-based feedstocks are currently converted to monosaccharides in high yields and we are not likely to see major advances in the established corn-to-ethanol route.

QQ How can improving processing efficiency of feedstocks impact land use for food crops? Developing genetically modified lignocellulosic crops specifically for biofuels, by altering their lignin type and content to facilitate deconstruction, increasing their cellulose content or reducing the content of acetate and other fermentation inhibitors, could significantly improve the amount of fuel that could be produced from the crop, thus decreasing land requirements. Such crops could also include modifications to confer drought resistance and salt tolerance. However, there may be an initial barrier to adoption of such genetically modified crops. In the USA, the RFS2 has placed a cap on the amount of corn-derived ethanol that can be blended into transportation fuels (15 billion gallons annually by 2022), thus limiting the fuel use of land suitable for growth of corn.

QQ Is it feasible to apply bioprocessing techniques to both developed and developing countries in order to ensure that competition for land is reduced globally? Production of transportation fuels from lignocellulosic biomass will require a fairly sophisticated production facility. Alternative approaches, such as biomass gasification or pyrolysis, may be more effective in developing countries. Biomass sources such as sugarcane, sugar beet, palm oil or starch will be region specific and depend on the availability and price of that crop, but provide much simpler routes for conversion to fuels. However, such crops could present competition for food or feed uses. In developed countries, subsidies for commodities and import tariffs make correctly assessing the impact of biofuel production from these crops, and the potential land use competition, very difficult [28]. The conclusion that biofuel production played a major role in the 2006–2008 commodity price boom has been reviewed and the biofuels contribution is thought to be much less significant[29,30] . Agricultural subsidies in the USA and EU (‘Common Agricultural Policy’) suppress agricultural prices with the result that much of the considerable land area available in developing countries is not used for food production. Use of this land for biofuels crops could have a positive economic impact without affecting food production; South Africa, for example, has developed such a strategy [101] .

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QQ What are the current limitations to improving bioprocessing techniques in relation to land-based feedstocks? The use of biomass feedstocks that are not employed for food production will do much to address the perceived issues in the food versus fuel debate. Developing the technology for converting the holocellulose content of ligno cellulosic biomass to fuels is thus key. Most biological routes rely on cellulase enzymes for saccharification, and the cost of these enzymes remains so high (>$1/gallon of ethanol [31]) that methods to lower enzyme requirements and/or reuse the enzymes will be necessary. Strategies for conducting non-aseptic fermentations using recom- binant organisms to produce fungible fuels beyond ethanol will also be necessary to reduce capital equipment costs. Producing fuels with carbon numbers higher than those of ethanol or butanol still presents a challenge in engineering metabolic pathways that have high carbon fluxes and in developing organisms that are less inhibited by either the fuels themselves or the inhibitors produced or released by biomass pretreatment methods. These challenges will be overcome by continuous research advances – there will be no ‘transformational’ changes, but rather steady progress. “ Developing the technology for converting the holocellulose content of lignocellulosic biomass to fuels is thus key. ” QQ Looking ahead, how much of an impact do you envisage bioprocessing having on decreasing land requirements for biofuel feedstocks over the next 5–10 years? I do not see bioprocessing having a significant impact in decreasing land requirements for biofuels feedstocks. The conversion of starch- and sucrose-based crops to fuels can be accomplished today at near theoretical conversions. Increasing crop productivity will have an impact, but agricultural and energy policies are more likely to result in major land use change. Re-examination of the assumptions made in the food versus fuel debate is likely to reveal the impact of biofuels is less significant than many of the other factors involved. If biofuels production from lignocellulosic biomass can be made competitive with petroleum-based fuels, the use of agricultural residues and crops grown on marginal lands might provide a means of avoiding the food versus fuel debate altogether.

Financial & competing interests disclosure H Blanch serves as Chief Science and Technology Officer of the Joint Bioenergy Institute, Lawrence Berkeley National Laboratory (a US Department of Environment-supported bioenergy research centre). He receives research report from the Energy Biosciences Institute, University of Berkeley California, USA. H Blanch has no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Bruce Babcock, Centre for Agricultural and Rural Development, Iowa State University, USA; [email protected] Expert in agricultural commodity markets and the impacts of biofuels

QQ Much of your research has looked into the economic impact of corn-based biofuels. How has this impact changed in recent years? If we had not had the great 2012 drought, the impact of ethanol on corn prices would have been quite modest this year, because growth in the supply of corn through expanded acreage would have far outstripped the growth in ethanol production. However, the drought has completely reversed things and now the impact of ethanol production could be quite high as the ethanol industry, the livestock industry and the export market compete for a sharply reduced supply of corn.

QQ What are the main factors that influence the relationship between food and fuel prices? Increases in fuel prices increase the demand for biofuels, and increased demand for biofuels increases the demand for feedstocks. The impact of the resulting feedstock price increase on food prices depends on the cost of the feedstock

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as a share of the final retail price of the food product. This means that if the feedstock is used directly as food, such as ground corn flour that is used as a staple cereal, then the share of feedstock cost is high relative to the final food price. In contrast, if the feedstock is corn and the corn is processed into high fructose corn syrup, which is used to make grape jelly, then the share of feedstock cost is low relative to the final food price. Because people in poor countries rely on relatively less-processed food, they are potentially more affected by feedstock price increases caused by biofuels than people in developed countries.

…the debate about food versus fuel will continue because many feel that it is immoral to use “ crops in that can be used to produce food for nonfood uses. ” QQ Do you feel that current US policy is striking the right balance between supporting the biofuel industry and managing food prices? Food price inflation in the USA is low. Most of the modest food price increases in developed countries consumers have seen have been due to energy price increases rather than commodity price increases.

QQ Is there a way to develop sustainable land-based biofuels that do not impact food prices? No. Increased competition for land resources will increase commodity prices, which will result in increased food prices, however modest the effect will be.

QQ In light of this, what would be your main predictions for food price fluctuations over the next 5–10 years in line with biofuel development? I believe that food prices will be largely stable after the temporary effects of the US drought have worked their way through the system. However, the debate about food versus fuel will continue because many feel that it is immoral to use crops in that can be used to produce food for nonfood uses.

Financial & competing interests disclosure B Babcock has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Shabbir H Gheewala, The Joint Graduate School of Energy and Environment, King Mongkut’s University of Technology Thonburi, Thailand; [email protected] Expert in life cycle sustainability assessment of land-based biofuels

QQ You have extensively studied the sustainability of land-based biofuels in Thailand. What have been the main sustainability concerns in recent years? First of all, it is important to mention that despite the worldwide interest in reducing GHG emissions and Thailand’s commitment to these efforts, the major driving forces for biofuels in Thailand have been the reduction in crude oil imports, stabilizing income of farmers, enhancing energy security by utilization of local feedstocks and diversification of the energy resources. These are directly related to the socioeconomic aspects of sustainability rather than environmental aspects primarily represented by GHG emissions. Therefore, although many studies have been conducted on the GHG implications of biofuels in Thailand [32–35], the decisive factors in terms of implementation have been feedstock availability and price [36]. This is also directly linked to the availability of land for additional feedstock plantation and increasing crop yields to meet the biofuel targets set by the government. A recent study showed that substantial benefits on employment would result both from ethanol as well as biodiesel, as compared with their fossil counterparts, as well as a net reduction in imports as a result of biofuels promotion in Thailand [37]. The main sustainability concern is to ensure that the economic benefits actually trickle down to the farmers for whom these are also intended. This is a crucial consideration, as a large percentage of them are smallholders who

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do not have much bargaining power; middle men and processing plants being the beneficiaries in many cases. Also, although environmental concerns are not the driving force for the promotion of biofuels, from a sustainability point of view these cannot be ignored. Consideration of the environment will be very important, and land areas to be converted to cultivation should, in particular, avoid forest areas, so that the GHG benefits can be made. Food prices will also need to be continually monitored because, on the one hand, an increase in feedstock prices is beneficial for the farmers and, on the other hand, the farmers and other poor sections of the society will be most affected if the food (feedstock) prices were to rise. It is important to note that food prices are affected not only by increases in biofuel production but also by other factors such as energy prices and market economics, including indirect effects such as speculation. In the case of palm oil, for example, econometric studies have shown that price of palm oil is affected much more by energy prices than the promotion of palm biodiesel [38].

An increasing population will of course increase demand for food but … the southeast Asian region is a highly “ productive region with a large agriculture base. ” QQ Much of your work has looked into GHG emissions from biofuels. How does altering land from food production to fuel production increase such environmental concerns? The increase of biofuel utilization in Thailand has been quite unique, in that for most cases existing crops have been utilized as biofuel feedstocks – sugarcane (molasses) and cassava for ethanol, and oil palm for biodiesel. For the case of ethanol, the government’s policy has been to use the excess feedstock (after accounting for domestic demand) for ethanol production. Of course the question then is how the export of these commodities would be affected. For the case of cassava, there have been several years where the prices of feedstock have been very low, causing much trouble to the farmers; hence it was hoped that the enhancement of cassava-based ethanol would help stabilize the prices. Export of cassava chips has been at very low prices too. However, of course one may argue about concerns of indirect land use change – changes occurring elsewhere due to cultivation of cassava to compensate for the reduced export. Modeling GHG emissions from indirect land use change has shown a substantial impact in certain cases where grassland in Thailand or elsewhere is converted to cassava [39]. Also, projections based on the government targets have shown that there may be a shortage of cassava within the next decade (assuming no expansion of cultivation area). For the case of molasses, there was already an excess that in some cases was being dumped; utilization for ethanol has created a market for this [36]. Thus, land use change issues are not occurring for this, at least in the near future. For the case of palm biodiesel, there has been a plan to expand the area under oil palm cultivation largely utilizing paddy fields abandoned due to low productivity (due to deterioration of soil quality), rubber (nominal amount) and fruit orchards (for those fruit that have faced low prices due to overproduction). Direct conversion of these lands to oil palm generally shows a beneficial effect on GHG emissions [40,41] . Inclusion of indirect land use change effects too does not increase the GHG emissions beyond those of fossil diesel, except if forests are displaced [41] .

QQ Are there any unique environmental conditions in Thailand and southeast Asia that limit the competition between food and fuel? Thailand, as well as other countries in southeast Asia, falls largely in the tropical zone characterized by high plant productivity. This has resulted in these countries having a large agricultural base and being food sufficient; Thailand is in fact a large exporter of many agricultural products – rice, sugar, cassava and pineapple being notable examples. The same holds for other countries in the region too; for example, Malaysia and Indonesia being the largest exporters of palm oil and Vietnam a large exporter of rice.

QQ With rising populations, do you feel that the competition for land between food and land-based biofuels will increase in southeast Asia? If not managed wisely, increase in land-based biofuels may increase the competition for land between food and fuels. This may especially be exacerbated when large countries in the region (e.g., China) increase the production of biofuels and, thus, the demand for feedstocks that might partly be fulfilled by importing from neighboring countries [42]. To be fair, regional trade also has economic benefits for the exporting country. With proper policies

644 Biofuels (2012) 3(6) future science group Ask the Experts News & Analysis

in place and good implementation, the negative effects of the competition for land can be minimized and the benefits enhanced. An increasing population will of course increase demand for food but, as mentioned earlier, the southeast Asian region is a highly productive region with a large agriculture base. Also, studies have shown that there is still a high potential for increasing the production yield with selection of good seed varieties and proper agricultural management; for example, appropriate fertilizer application and utilization of field residues. Increased demand for farm produce will enhance the urgency for achieving the high potential yields.

QQ As such, what are your major concerns regarding global land use change due to biofuel production over the next 5–10 years? With rising concerns of sustainability issues concerning biofuels and with many international criteria developed by organizations such as the Roundtable on Sustainable Biofuels and the Global Bioenergy Partnership, biofuels are very much in the focus. In the previous decade, many countries had set ambitious biofuel targets; however, it seems that the ambitions in the future may be more tempered, and the policies that are already set and being implemented would most likely continue for the coming 5–10 years. How much biofuel production will actually influence land use change is a matter of conjecture. Many models are being used to predict the impacts of biofuels production, particularly indirect land use change [43]. However, these depend on many assumptions and are fraught with uncertainty [44,45]. In summary, a good way to approach global land use change issues is to try and minimize it via policy mechanisms promoting inter alia agriculture intensification and forest protection [45,46].

Financial & competing interests disclosure SH Gheewala has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

David Zilberman, University of California, Berkeley, USA; [email protected] Expert in economic impact of genetically modified organisms

QQ What have you found to be the main advantages of genetically modified organisms? Genetically modified organisms (GMOs) provide a new avenue to accelerate crop breeding and develop crop varieties that we were not able to develop before. I believe that the most important contribution of GMOs has been in increasing the precision of crop breeding, allowing us to alter rates while preserving a variety. GMOs have also enabled new pest-control solutions, which are very valuable due to their large impact on yield. Therefore, GMOs have allowed us to, in many cases, increase yield, reduce prices and replace toxic chemicals with solutions that are more environmentally friendly.

QQ How have GMOs impacted crop development in recent years? I am an economist so, therefore, I have studied the advances on the economic impacts of GMOs, which are increases in yield and acreage but also the reduction of pesticide use. In the USA, GMOs were used to replace pesticides and did not increase yield very much, maybe 5–10%, but they did decrease toxic chemical use. However, in countries where GMOs were used to address pests that had not been controlled by chemical pesticides, GMOs increased yield substantially; Bt cotton increased cotton yield per hectare by more than 50%. As such, the impact of GMOs on crop development has varied by location as well as crop. In terms of farmed area, there has been a big impact in soybeans. Double-cropping soybeans has been allowed by GMOs, which has increased the production in areas with severe weed problems. For example, in Argentina herbicide-tolerant GMOs allow the ability to grow both wheat and soybean each year on the same land; this means that output increased but the agricultural footprint did not. The increase in yield and farmed area due

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to GMOs contributed to increased total output of crops in recent years and reduced negative effects on agricultural commodity prices. These price effects were of the same order of magnitude, or even bigger, than those of biofuels but in the opposite direction.

QQ Exactly how have advances in GMO technology impacted biofuel production? If it were not for GMO technology, the prices of cotton, maize, rapeseed and soybean would be much higher. We know that the introduction of biofuels increases the price of commodities. However, the fact that you have GMOs means that it is possible to counter the increase in prices associated with biofuels and, to some extent, neutralize it. In my view, the main cause for the increase in the price of food is population growth and rising incomes; these increases will continue to increase food demand and raise food prices, no matter what we do. However, GMOs increase productivity and can counter these effects.

QQ Does this have the potential to reduce the competition of land between food and fuel? Now, this is the most intriguing point: GMOs have not been fully adopted. GMOs have only been adopted in the USA, Argentina, Brazil, China and India for cotton but not for wheat or rice. Our calculations suggest that the food–fuel dilemma could be avoided if we took full advantage of biotechnology, which would lead to increased supply and reduced agricultural commodity prices. Biofuels do a lot of good for farmers; they increase income and induce investment and innovation in agriculture. Yet, current food prices present a big challenge. Allowing the expansion of the use of biotechnology enables biofuels to become, instead of a problem, a source for sustainable fuel supply as well as allows us to reduce the price of fuel and adapt to climate change.

Allowing the expansion of the use of biotechnology enables biofuels to become, instead of a problem, a source for “ sustainable fuel supply as well as allows us to reduce the price of fuel and adapt to climate change. ” QQ What challenges lie ahead for GMO technology to help reduce the competition between food and fuel? There are many obstacles for the adoption of GMOs. The main obstacles are the negative attitudes from environmental groups and NGOs leading to excessive regulation, intellectual property and emergence of resistance to GMO varieties. There are, in my view, many irrational objections and political constraints towards the adoption of GMOs in Europe and in Africa – a lot of unwarranted fear that has introduced regulations to introducing GMOs. Most leading national academies of science have found that GMOs are as safe as conventional food and have major environmental and health benefits. Regulation is needed. There is no doubt that GMOs have to be safe. However, sometimes regulations are excessive. In Europe, countries have set incredible barriers to the testing and use of GMOs, making them illegal or noneconomical. Many African countries are now afraid of using GMOs because EU countries have influence and provide a market for African agricultural exports. Therefore, I feel that many of the barriers to the use of GMOs should be re-examined, relaxed and, in some important cases, eliminated. I do not deny that GMOs face challenges. The introduction of GMOs does not mean that we practice without caution. Altogether, GMOs can be used very effectively if you have regulation – that is, if you develop regulation that enables and protects rather than disables and restricts. There is also the challenge of intellectual property. You need to have a legal environment where intellectual property barriers can be overcome and people can develop and introduce GMO varieties to new crops, especially when used for feeding vulnerable populations. The good news is that there are mechanisms to avail access to technology for developers of technologies for the poor. Furthermore, in a few years the patents for many crucial transgenic technologies will expire and then new parties will start utilizing these technologies. Heavy regulation, in my view, has caused us to lose approximately 10–15 years of development of new varieties; we could have had a lot more use of GMOs by now. Instead, we have reduced our ability to improve food supply, adapt to climate change and develop biofuels at a sustainable rate.

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QQ Do you feel that these challenges could be overcome in the short term and end the food versus fuel debate? We have to overcome the barriers that prevent us from taking advantage of genetic knowledge and using it to increase food supply. I believe that the resistance to GMOs will get worse before it gets better. Historically, there has always been resistance to radical innovations, such as the automobile. Many major technologies have 10–30 years of resistance that slows their development. Some chemical companies dislike GMO technologies because they reduce the need for their pesticides. However, patents are expiring and, therefore, a lot of companies that originally thought GMOs were a terrible idea will see it as a good opportunity. I feel European companies will slowly move to GMOs because they will be able to take advantage of it as patent barriers decline. Consumers do not realize that they will be the bigger winners from GMOs. What will happen is the consumer will realize that food prices are getting too high, which will make people think twice. It does not matter if it is a red cat or a white cat. As long as it catches mice, people will start to give GMOs a chance. Ultimately, I feel that higher food prices will lead people to GMOs, to help build for long-term sustainability and increased food and biofuel production. I am sure there will be problems and even some accidents but, all in all, GMOs will be a tool that will allow for a sustainable future. My feeling is that biofuels will grow much further once we have completed more research into second-generation biofuels that do not compete directly with food and can take advantage of resources that are underutilized. Throughout the process, both the private and public sectors have invested hugely in research. We are in the early stages of research on biotechnologies and biofuel, and high returns are ahead of us.

Financial & competing interests disclosure D Zilberman works with the Energy Biosciences Institute, which is funded by a BP grant. The author has no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

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