Sustainability aspects of biofuels (0)

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Margit Tepner k0848752
Sustainability aspects of biofuels

Introduction
The literature review will discuss the sustainability aspects of biofuels. Food production will be the main concern as it is the most debated issue , but other aspects, such as land use change and water consumption will be also considered as they are essential aspects in the biofuels sustainability criteria . The review will discuss the viability of biofuels based on the current technologies. Second-generation biofuels are not yet commercially viable and therefore will not be discussed; although they could significantly improve the sustainability of biofuels when they break through to the industrial scale .

The scale of biofuels production
2.1. Drivers of biofuels production
Lal (2010) stated that “three inter -connected challenges face humankind in the 21st century”: food security , climate change, and energy security. The world population is projected to reach 9 billion in 2050, posing more demands on energy, food, and other natural resources. It has been estimated that the world food production needs to double and meat production increase by 85% by 2050 to fulfill projected demand by population (Karp, 2011). In the recent decades, the food consumption in the most populous counties has shifted from grain-based diets to meat and dairy diets. Meat production requires times more biomass in the form of animal feed and that puts further pressures on natural resources. As food production is very energy intensive , it is closely linked to global energy consumption. Global fuel consumption has grown 50- fold since the end of the 20th century and it is projected to increase by another 55% by 2030 (Umbach, 2010). That is the reason why new resources for fuel are being sought and biofuels receive subsidies, and investment in development . In addition , transport sector is one of the largest primary energy consumers, and as the travel and car ownership is predicted to increase, more fuel needs to be dedicated to transport (Karp, 2011. There are many reasons why biofuels are necessary , but at the same time, they are controversial for a number of reasons.

Biofuels’ feedstock and future projections
There are mainly two types of liquid biofuels, which have significantly grown in the last decade: that is bioethanol and biodiesel. Bioethanol is based on sugar , extracted from sugarcane and beet, or starch, which mainly comes from maize, wheat or cassava. Starch-based crops must be first converted into sugars in the saccarification process, which requires substantial volumes of enzymes to turn starch into sugars (Soetaert, W. 2008). The starchy products represent only a small percentage of the total plant mass. Other plants ’ building blocks like cellulose and lignin are currently not being used to make biofuels as there is not a commercial viable production method for making ethanol form cellulosic biomass (FAO, 2008).
Biodiesel is based on the oil crops, such as rapeseed in Europe and soybean in the USA and Brazil . In tropical regions , biodiesel feedstock can also be sourced from palm , coconut and jatropha oils, but these are currently not major feedstock for biodiesel. Biodiesel is produced by combining vegetable oil with an alcohol and a catalyst through a chemical process known as transesterification (FAO, 2008).
Figure 1. Proportion of global production of liquid biofuels (FO Licht , 2007). Biofuels production is concentrated in three countries: Brazil, the USA, and Europe
On a global scale, there are three regions that produce biofuels: mainly France and Germany in Europe, the USA, and Brazil. Each region specialises on a specific crop, and the production technologies vary greatly. Biodiesel is concentrated in Europe and in 2005 France and Germany supplied 69% of the global biodiesel. Bioethanol production is concentrated in two countries: Brazil and the USA and in 2005, they together accounted for 80% of global ethanol production (Msangi et al. 2007; Zuurbier, 2008). While Brazil’s biofuels production has grown steadily since the 1980s, then in the USA, the production started to hike in 2003 with the Renewable Fuel Standard legislation . In Europe, biofuels production started to rise in 2005, as depicted on figure 2.
Figure 2. World biofuels production ( F.o. Licht’s World Ethanol and Biofuels Report , 2006)
Figure 3. Global biodiesel production projection (USDA, 2012). Biodiesel is mainly produced in Europe, but production in other countries is expected to increase.
In Europe and the US, biofuels have been boosted with the government ’s goals to source certain percentage of transport fuel from biofuels and therefore biofuels production is heavily subsidised. For example, in the EU, by 2020, 10% of energy used in transport should come from biofuels. In the USA, there is a fixed quantity of renewable fuels that must be consumed each year. By 2015, it must be 15 billion gallons, and 36 by 2022 . In the USA, the legislation also requires to source fuels from advanced biofuels. Babcock (2008) has stated that, in the future, biofuels production will be determined by the level of crude oil prices and public policy incentives. So far, policy incentives have been key drivers of biofuels’ production in Europe and the USA.
Figure 4. Global bioethanol production projection (USDA, 2012). Bioethanol is mainly produced in Brazil and the USA.
Biofuels production and its increase in the future is closely linked to the oil prices. A study (Timilsina, 2011) has found that 25% increase in oil price (from 2009 baseline figures ) in 2020 would cause a 20,4% increase in global biofuel production. In turn, increasing oil prices would shift land away from food production as it becomes less profitable . Secondly, increasing oil prices would especially increase the food prices in countries, where its production is energy intensive.
According to the International Energy Forum Report, the targets set by the European and US government won’t be achieved, but biofuels production will still increase significantly. It is projected to rise from today ’s 1% to 7%, in 2030. The highest rise in biofuels will take place in US, Europe, Asia and Brazil (IEF, 2010).

Competition with food production
In the literature, there is a general consensus that biofuels do compete with food production, but the relationship is neither straightforward nor simple as there are other factors that influence the prices of food and its production (Fammini, 2008; AJanovic, 2010). As was described in by Fammini (2008), the 2007-08 food price crises had a number of factors playing for it. One of the underlying causes was the rising demand for food crops from developing countries, such as China and India. The demand has particularly grown for meat and dairy products, which implies increased demand for animal feed. That factor ties closely in with the reduction of international crop stock levels, which usually helps to ease the consequences of reduced supply . Food reserves have gradually reduced sine the 1990s and the main reason is to decrease stock holding costs . Increased fuel prices and food speculations by the financial institutions have also influences the food prices and its supply. In addition, during 2006, cereal production in major exporting countries declined by 7% due to adverse climate conditions (Fammini, 2008).
Nevertheless, since the biofuels production has grown three fold between 2000 and 2007, as can be seen on figure 5, it has had an impact on the food industry. For consumers the impact mainly translates itself into higher prices for food products.
Figure 5. Global biofuel production tripled between 2000 and 2007 (IEA, 2009).
3.1. Maize
Maize is the primary feedstock for bioethanol in the USA, where demand for ethanol has increased the total demand for maize. Biofuels’ feedstock production has shifted the land area away from maize for food and animal feed production. On the other hand, as maize is more profitable to grow due to biofuels, some farmers have shifted their cultivation from rice and wheat cultivation to maize. As a result , the prices of all staple crops, such as rice, wheat and maize have been affected (Rosegrant, 2008).
Corn is one of the most widely used food staples in the world. In 2005, the US produced 42% of the world’s corn and it is has a variety of uses. About 50% of the field corn grown in the USA is used for animal feed, but smaller volumes, i.e. 10% is used for direct human consumption in corn based meals. Corn is also important in providing cooking oil and margarine in the USA. In addition, corn sweeteners supply more than 56% of the sweeteners market in the US (Soyatech, 2012). Nevertheless, it has been hard to predict how decreased production actually has impacted the food market. Corn’s primary utilisation is in animal feed, and even then it is often mixed with other feed types. Corn’s higher prices on the first hand result in substitution with other feed cereals , which does not necessarily result in increased food prices (Leibtag, 2008).
Figure 6. USA corn usage (USDA, 2012). In the USA, corn is a major source of bioethanol feedstock. Other major usage of corn is animal feed.

Wheat
Wheat is one of the leading staple crops in the world. Its production grew dramatically between 1961 and 2007, from 222.4-607 million tons. Wheat has high concentration in Western Europe, eastern USA, and China and India. Global wheat production is focused in relatively high-yielding areas : about 40% of the world’s wheat output comes from the 20% of cropped areas reporting to highest yield (Pardey, 2011). Although wheat is the most cultivated crop in the world, it is not a major crop for biofuels. Wheat prices have seen the most dramatic rise amongst all cereals, but the use of wheat for biofuels production is modest and, therefore, an argument that biofuels currently compete with wheat production bears little weight (Timilsina, 2011; Defra 2008). Nevertheless, wheat is produced in countries, where consumption of biofuels is projected to grow the most, such as the USA and Europe and that can affect the wheat cultivation for food in the future.

Sugarcane
Sugarcane grows only in tropical areas and it is a very efficient and productive crop for biofuels. Brazil is the major sugarcane producer, where the production of ethanol from sugar cane started in the 1980s and has grown to 22.24 billion liters in 2007 (Zuurbier, 2008). Sugarcane is used as a feedstock for producing bioethanol and the residual leftover – bagasse - is used in heat and power generation. That is one of the characteristic that gives sugarcane production an advantage over other fuels.
But sugarcane is also the major source of sugar in the world; about 80% of today’s sugar is made from sugarcane, cultivated in tropical and subtropical areas of the southern hemisphere. In Brazil, however , sugarcane utilisation for biofuels does not pose competition for sugar production, as sugarcane occupies about 10% of the current planted area, and only 50% of it is used for ethanol feedstock. Sugarcane cultivation takes up only 2.5% of the total agricultural land available and it has been predicted that there is plenty of potential for agricultural expansion (Padula et al, 2007). It is well accepted that, in Brazil, the current large-scale sugarcane production does not compromise food production, and even an expansion would be possible without constraints. Sugarcane is mostly cultivated in the southeast region of Brazil and sugarcane production has limited impact on deforestation , because the soil and weather conditions in the Amazon are not suitable for sugarcane. Nevertheless, large areas dedicated for sugarcane production limit the land availability that can be used for other crops. In areas, where sugarcane is primarily produced, the production of oranges, cattle and other crops have lost space to sugarcane (Padula et al. 2007; Bowen, 2010).

Soybean and rapeseed oil
The global oil consumption has increased significantly in the last decades, especially palm and soybean oil, as can be seen on figure 8. The report commissioned by IEA states that increased demand has been sparked off by higher consumption of edible oils and not by biofuels. The graph 7 also indicates that only a small proportion of oil currently produced is used for biodiesel. In Europe, the main producer of bioethanol is Germany. Domestically produced grapeseed oil is mainly used for fuel, but about 20% in 2007 was used for food (Rosillo-Calle et al. 2009).
Figure 7. Worldwide vegetable oil use (FAS, 2012).
It has been estimated that if they EU is to achieve its targets, than a majority of the oil for biodiesel needs to be imported (Rosillo-Calle et al. 2009). Producing biodiesel is projected to compete with the food market as the demand for edible oil has also increased over the years . There is also a concern for the sustainability of tropical crops, such as palm oil, which cultivation has already caused acute deforestation in the recent decades (Soetaert, Vandamme, 2009). IEA (2009) has concluded that prolonged dependence on fossil fuels will increase the risk of deforestation, especially in Indonesia. UNEP (2009) predicts that 2/3 of palm oil cultivation is based on rainforests territory and that rainforest would be reduced by 29%, compared to 2005 levels, if the current trends and demands for biofuels continue.
Figure 8. Worldwide vegetable oil production 1975-2007 (FAS, 2012).
In Brazil, besides bioethanol, biodiesel production has also seen an increase since 2005. In Brazil, 90% of biodiesel uses soybean as the main feedstock, which is also an important animal and human feed source. It is high, both , in oil and protein , and on a global level, some 85% of the soybean is processed into animal feed (Soyatech, 2012). The production of soybean is mainly concentrated in Mato Grasso and southern states of Brazil, but it is also suitable to cultivate in the Amazon rainforest. Unlike sugarcane, soybean can pose competition to food as it is primarily used for animal feed. Therefore, reduced cultivation of animal feed would especially impact meat. Soybeans cultivation can also result in deforestation due to land-use changes . A study (Lapola et al., 2009) concluded that in the future, soybean production is likely to be a cause of a direct deforestation in Amazon. It will also be responsible for 60% of indirect deforestation as rangelands will be moved to Amazon region due to the competition for land in other areas (Lapola et al.,2009).

Other sustainability concerns
4.1. Greenhouse gas (GHG) balance
One of the advantages for adopting biofuels is the offsetting of carbon in the production process. Biofuels are carbon neutral when their combustion doesn’t release any more carbon dioxide into the atmosphere, than was sequestered by the plant through photosynthesis (Rajagopal, Zilberman, 2007). Nevertheless, there are many uncertainties around the biofuels’ carbon neutrality. In the production process, biofuel require significant amounts of energy for tillage , fertilizers, pesticides, irrigation and for harvesting. Nitrogen oxide from fertilisers are known to be particularly potent greenhouse gases with 300 times more potential than CO2 and it has a harmful effect on the stratospheric ozone (Schaerlmann, Laurence, 2008). Also, as in any other agricultural production, biofuels can cause erosion and eutrophication due to fertilizer runoffs (Rajagopal, Zilberman, 2007). According to the International Energy Agency Report (2007), the fossil energy balance for different biofuels varies greatly, depending on the feedstock productivity, production and conversion technologies. For example, using coal in the production processes can worsen the GHG emissions significantly (Menichetti et. al.,2009).
Figure 9. Percentage of GHG savings (Menichetti, 2009). Among the studies on biofuels ability to reduce GHG emissions, there is a great range.
Besides balancing the fossil energy ration in the production process, clearing land for biofuels feedstock production will release significant amounts for GHG emissions. Soil and plant mass are the largest active stores of carbon on the Earth. Converting native habitats to cropland can release CO2 as a result of burning the biomass. After a rapid GHG release from an initial fire to burn the original biomass, there will still be a long prolonged period, when GHG is released , as coarse roots and root branches decay . It has been estimated that clearing land would release between 17-420 times more CO2 than the annual GHG emissions the biofuels would save by replacing fossil fuels (Farigone, 2008). Another study has concluded that converting forests and grasslands to new croplands can double the GHG emissions for 30 years (Searchinger, T. 2008).
Despite the real threat to deforestation, some studies suggest that biofuels can be successfully grown on marginal lands, such as abandoned agricultural soils, saline soils and reclaimed mining areas (Reijnders, 2008). However, it is highly that biofuels demand can be satisfied only with crops grown on marginal lands. Also, currently, the legislation does not incentivise such approach .
It has been stated by the International Energy Forum that at present , only ethanol produced from sugarcane in Brazil is a viable option when considering the GHG balance, and other aspects as well. Ethanol produced from sugarcane has a competitive advantage over maize and corn feedstock, because the sugars can be directly diverted into ethanol. Also, unlike wheat, sugarcane industrial processing is often powered by sugarcane’s by-product, bagasse.
The main problem that overshadows the assessment of biofuels GHG emissions is the various advantages and disadvantages of all the different biofuels. As pointed out by Scharlemann and Laurnce (2008), there is no “common currency ” for comparing biofuels, as each biofuel has certain benefits and costs. The article explains a study (Zah et al.,2007), where, on assessing biofuels against GHG and all other environmental costs, it was found that most biofuels reduce greenhouse gas emissions, but have other severe environmental costs. It suggests that there is a need to consider more than just energy and GHG emissions when evaluating different biofuels.

Water
Any biomass cultivation requires water consumption, and for biofuels’ feedstock production, it can become a constraint. Water shortage is predicted to become particularly acute for sugarcane in India, and wheat or maize in Northern China. In Sub-Saharan Africa, biofuels feedstock production at a larger scale would also require irrigation investment and large-scale soil fertility improvement, i.e. higher levels of fertilizer application (Msangi et al.,2007). Increasing biofuels production will also impact water quality due to the use of agrochemicals and harmful substances produced in feedstock processing and conversion. To increase biofuels’ water consumption sustainability, its feedstock cultivation under irrigated conditions should be discouraged (Ajanovic, 2010).

Conclusion
The global food production is affected by a number of factors: diets, population, energy prices, and so far, biofuels have not significantly impacted the food production. Nevertheless, some studies suggest that corn crops have shifted land area away from other crops’ cultivation in the USA, and therefore increased the prices of wheat, rice and other crops. Similar findings have been discovered in Brazil, where sugarcane production has increased the price of arable land in some areas and shifted the production away from oranges, for example. Overall, such effects seem to be more local , rather than global, and a worldwide decreased in food crop cultivation in response to biofuels increase cannot be determined.
However, predictions from the international NGOs, such as UN and FAO predict that in the future, biofuels will significantly impact the food production and deforestation in Indonesia and Brazil. Nevertheless, as biofuels’ feedstock and technologies are different in every country each production process needs to be evaluated separately. For example, sugarcane and soybean in Brazil have different consequences, as they have alternative applications and growing conditions vary. Soybean is primarily used for animal feed, whereas sugarcane does not have any other major uses. In Europe, although wheat is not a major source of biodiesel’s feedstock, its production can grow due to biodiesel’s demand, which would seriously affect the food production as it is a major staple crop across the world.
At present, the main drivers for biofuels are the legislated targets in public policies. Most biofuels, except ethanol from sugarcane in Brazil, are not commercially viable without those subsidies. However, financial incentives are important in driving the research and development of biofuels, and especially the research of second generation biofuels. All in all, biofuels and their development will be necessary to meet the future’s energy demand and sustain secure and affordable energy sources .
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