Biofuel development in Latin American and the Caribbean

“SUPPORTED BY THE

PROGRAMME ALBAN, THE EUROPEAN UNION

PROGRAMME OF HIGH LEVEL SCHOLARSHIPS FOR LATIN

AMERICA, SCHOLARSHIP NO. E06M100312MX”

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ACKNOWLEDGMENT

Several persons have been actively involved in allowing this thesis to be concluded. First of all, I would like to thank my first supervisor, Prof. Dr.-Ing. Gerhard Lappus for accepting my topic and enable me to work in this particular field. I would also like to acknowledge my second supervisor, Dr. Jörg Becker for his time and consideration giving me useful hints and thought-provoking ideas. He provided me with the most valuable guidance and critique for the completion of this thesis.

My friend Andrea Tönjes deserves credit as well because of her support teaching me how to put together the pieces of my (sometimes) disjointed thoughts. Additionally, I would like to thank PD Dr. Oliver Dilly from the Chair of Soil Protection and Recultivation for his important inputs to this thesis.

Thanks also to MSc. Piotr Jaworski for the time he invested providing me with scientific support.

I would also like to thank my “Cottbus family” for their encouragement for developing

this topic (I will not forget that late night kitchen-debate that shaped the beginning of this wonderful project - Thanks Lauro!). Juan Pi Gutierrez deserves a special mention. He managed to be surer of my ability than myself from the beginning of this venture. Moreover, I would like to give my appreciation to Ivan Zaleta, with who I am immensely indebted for his inspiration and support, professionally and personally. Naturally, I would also like to thank my family, which makes everything I do, possible. Finally, I would like to express my gratitude to the Programme Alßan. Without its support it would not have been feasible for me to carry out and to complete this project.

AFFIDAVIT

I hereby declare that all information disclosed in this thesis is a product of my original

and individual work. Neither this work in its complete form, nor any of its parts has been submitted to any university other than the Brandenburg University of Technology for the award of any academic degree.

Furthermore, I confirm that all sources other than my own have been duly acknowledged. Place, Date (Signature)

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FOREWORD

In the light of availability concerns and environmental implications of fossil fuels, attached with the remarkable rise in the price of oil during the past several years; biofuels are getting a significant increase in interest worldwide from governments, private investors, farmers and the public in general.

Nevertheless, the use of cropland for biofuels had become a very controversial topic. On one hand, promoters state that biofuels represent opportunities to increase the energy security and to generate environmental and social benefits (through greenhouse gases emissions reductions and poverty alleviation through rural development respectively). On the other hand, topics such as the effects on food prices and availability, soil fertility and erosion, competition for scarce land and water resources and biodiversity loss are also widely discussed as important concerns related to further development of bioenergy. Notwithstanding this, several developing countries around the world are turning into the biofuels direction to satisfy the demand of developed countries while contributing to their economical growth and/or diversifying their current options of energetic arrangements. For Latin America and the Caribbean (LAC), a geographical area with privileged natural resources; home-grown energy crops emerge as an appealing possibility, especially given the example of Brazil, a historical leader in ethanol production.

After assessing some core elements of the biofuel’s debate, the evidence seems to suggest that biofuels may represent a valuable source of renewable energy. Nonetheless, in order to represent a promise to the LAC region, local governments will be required to firmly normalize land use and agricultural activities, while cautiously shaping public policies. Whether the biofuels’ boom will represent an opportunity or a risk for the LAC region would depend on how each country regulate agricultural and manufacturing practices, including how many small farmers and workers from rural areas would benefit from the industry.

Keywords: Renewable resources, Biofuels risks and opportunities, Latin America and

the Caribbean, Ethanol, Biodiesel, Food vs. Fuel debate, GHG reduction, Holistic

approach to biofuels.

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TABLE OF CONTENTS

  Acknowledgment  iii

  Affidavit  iii

  Foreword  iv

Table of contents v

List of abbreviations vii

List of tables viii

List of figures ix

1.  Introduction  1

1.1  Motivation  1

1.2  The area under investigation  2

1.3  Research objectives and scope  3

1.4  Intended significance  3

1.5  Structure of the paper  4

1.6  Research methodology  5

2.  Global energetic overview  6

2.1  Latin America and the Caribbean: Regional profile  8

2.1.1  Natural resources  9

3.  Biofuels and their production  11

3.1  Definition of biofuels  11

3.1.1  Sources of biofuels  12

3.1.2  Alternative biofuels production pathways  13

3.1.3  Vehicle fuel compatibility  18

3.2  Biofuels globally  21

3.2.1  Production  21

3.2.2  Consumption  23

3.2.3  Future perspectives  24

4.  Brazil  25

4.1  Outlook  25

4.2  History  29

4.3  Is Brazil ethanol really a model to follow  33

5.  Latin America the Caribbean and the use of bioenergy  37

5.1  Latin America and the Caribbean: biofuels drivers  38

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5.2  Regional potential  42

5.3  Biofuel policy implementation  46

5.4  Biofuel production  51

5.5  Conclusion  56

6.  Biofuels opportunities  59

6.1  Green House Gases (GHG) reduction potential  59

6.2  Energy security  66

6.3  Rural development  68

7.  Biofuels risks  70

7.1  Food security- the food vs fuel debate  70

7.1.1  Food price inflation  71

7.1.2  Proposed action  74

7.2  Environmental impacts and biodiversity loss  75

7.3  Water scarcity  79

8.  Discussion and criticism  82

8.1  Latin America and the Caribbean: Undeniable potential  86

8.2  Biofuels in Latin America and the Caribbean: Key questions  87

8.3  Other externalities  89

8.4  Measures  90

8.5  Extras  93

9.  Conclusions  95

  Annex 1: Glossary  97

  References  101

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LIST OF ABBREVIATIONS

CO 2 carbon dioxide

CONCAWE Conservation of Clean Air and Water in Europe

E-5 5 % blend of ethanol/ gasoline E-10 10 % blend of ethanol/ gasoline

EIA Energy Information Administration

EU European Union

FAO Food and Agriculture Organization of the United Nations

GHG greenhouse gases

ha hectare

IEA International Energy Agency

IPCC Intergovernmental Panel on Climate Change

JNCC Joint Nature Conservation Comitee

Kg kilogram

L liter

LAC Latin America and the Caribbean

OAS Organization of American States

OECD Organisation for Economic Co-operation and Development

OLADE Organización Latinoamericana de Energía (Latin American Organisation of

Energy)

UNCCD United Nations Convention to Combat Desertification

UNDP United Nations Development Programme

NNEC Network for New Energy Choices

UNFPA United Nations Population Fund

USCIAUnited States, Central Intelligence Agency

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LIST OF TABLES

Table 1  Top five fuel ethanol producers in 2005  22

Table 2  Top five biodiesel producers in 2005  23

Table 3  Brazilian s ethanol exports in million of litres  28

Table 4  Latin America and the Caribbean countries energetic profile  39

Table 5  South American countries biofuel potential  43

Table 6  Central American countries biofuel potential  45

Table 7  Caribbean countries biofuel potential  46

Table 8  South American countries legal framework development in relation to biofuels  47

Table 9  Central American countries legal framework development in relation to biofuels  49

Table 10  Caribbean countries legal framework development in relation to biofuels  50

Table 11  South American biofuel production  51

Table 12  Central American biofuel production  55

Table 13  The Caribbean biofuel production  55

Table 14  US fuel ethanol imports by country (2002-2007)  55

Table 15  Ethanol from grains  62

Table 16  Ethanol from sugar beets  63

Table 17  Biodiesel from Fatty Acid Methyl Esters  64

Table 18  Ethanol from Cellulosic Feedstock  65

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LIST OF FIGURES

  Figure 1 World energetic consumption (1981-2006)  6

  Figure 2 Regional consumption pattern (2006)  7

  Figure 3 Ethanol Production steps by feedstock and conversion technique  13

  Figure 4 World fuel ethanol production (1975-2005)  21

  Figure 5 World biodiesel production (1975-2005)  21

  Figure 6 Percentage of global production of fuel ethanol and biodiesel (2006)  22

  Figure 7  26

  The Brazilian energetic matrix (2005)  

  Figure 8  27

  Brazilian s ethanol production (2000-2010)  

  Figure 9  32

  Ethanol fuel production by year  

  Figure 10 Potential for expansion of farm land once an E5 blend has been achieved  56

  Figure 11 Potential for expansion of farm land once a B5 blend has been achieved  57

  Figure 12 Index of per capita food energy supply  73

  Figure 13 Holistic approach to the problem (1)  83

  Figure 14 Holistic approach to the problem (2)  84

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1. INTRODUCTION

1.1 MOTIVATION

Today, the modern global community is greatly dependent on non-renewable resources, especially, on fossil fuels. Growth of their employment for long periods of time had taken place as if there were not limitations in terms of availability or environmental implications. Nevertheless, fossil fuels (especially oil) are distressed by geopolitical complexities that augment price instability, affecting the economy in global terms.

In the light of the remarkable rise in the price of oil during the past several years and considering that they can replace petroleum fuels in today’s vehicles; biofuels are getting a significant increase in interest from governments, private investors, farmers and the public in general worldwide. Therefore, it should not be a surprise that biomass is considered by some players as a feasible alternative to comply with the current energy requirements.

Promoters state that biofuels represent opportunities to increase the energy security and to generate environmental and social benefits (through greenhouse gases emissions reductions and poverty alleviation through rural development respectively).

On the other hand, topics such as the effects on soil fertility and erosion, competition for scarce land and water resources, and biodiversity loss are also widely discussed as important concerns related to further development of bioenergy.

Maybe the most controversial implication of biofuels expansion is the significance of agricultural resources for food security worldwide. This aspect has been intensively discussed in the scientific and political sphere.

This last point is exactly from where the main motivation of this research came from. It came from the concern about the possibility that large scale political decisions in this matter would be justified notwithstanding social and environmental costs. This unease might have been aggravated by the fact of coming from a net food importing country.

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The actual impacts of the biofuel industry development are part of an always uncertain future. A promise? A risk? It is said that its consequences will vary depending on the evolution of technological developments, market structures and legislation frameworks at national and international levels.

The complexity of the situation and the role of different interest groups in local, regional and global levels are the some of the objects under research in this Master Thesis.

1.2 THE AREA UNDER INVESTIGATION

It had been suggested that Latin America is the geographic area with more contrasts among countries. There are noteworthy variations regarding the distribution of wealth, incomes and opportunities. In addition, one of the most important aspects of inequality among the region’s population is the unequal access even to basic infrastructure for example electricity, water and drainage.

Undernourishment and rural poverty are some of the region's main challenges even when sources such as FAO/GBEP (2007) had suggested that these countries have sufficient food production and had shown economic regional growth.

As it will be discussed on chapter 5, the Latin America and the Caribbean area is getting a lot of attention in regard to biofuels development because it hosts Brazil, an important biofuels producer, and because its richness in biomass resources. Besides, the region enjoys other advantages such as long growing seasons, tropical climates, high precipitation levels and low labour and land costs. Furthermore, many countries have the interest of balancing their energetic mix without risking their further development.

These contrasts and similarities at a regional level make this study even more interesting and challenging. Therefore, an analytical framework intends to take into consideration these aspects in the countries under study including Mexico (in North America), the countries located in Central and South America plus the Caribbean Islands.

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1.3 RESEARCH OBJECTIVES AND SCOPE The objectives of this Master Thesis are various. First of all, it is intended to give an introduction about what biofuels are and how they are produced, making a brief comparison among different pathways of production. This study focuses on two biofuels produced with organic matter: ethanol and biodiesel.

After, the study would try to describe the current situation of biofuels, from a general perspective (worldwide) and then narrow the scope to the countries under research making a distinction among Brazil and the rest of Latin America and the Caribbean. The core element of this case analysis comes then with the exploration of the possible risks and opportunities of the enlargement of the biofuel industry with a specific focus on the region. The paper will review the potential effects of bioenergy on climate change, food security, biodiversity, and rural development.

This analysis will make a discussion come up about some requirements that need to be tackled bringing ideas for a sustainable performance in terms of both environmental and social impacts.

The main objective of the whole research is in principle to maintain a scientific position carrying out a study comparing some of the findings available in literature. With a critic focus, the objective is not to present a position so as to either support or attack the development of biofuels. On the other hand, it is written in order to find possible mitigation measures in the case that big scale political decisions are made in this matter, always highlighting the complexity of the implications of the biofuels industry.

1.4 INTENDED SIGNIFICANCE

For some actors, biofuels represent a feasible choice for a more sustainable array of energy options. But truly, opportunities come with challenges. Many aspects should be taken into consideration to proceed making informed decisions; considering the chances and trying to minimize the potential negative effects.

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This case analysis intends to depict a comprehensive picture of the system of actors and structures which have a stake in the use of the agricultural resources, bearing in mind the land and water resources and the importance of agricultural resources for food security.

The discussion recalls that biofuels should be an alternative only if they are socially and environmentally sustainable (and not only economically beneficial).

1.5 STRUCTURE OF THE PAPER

The following chapters cover various aspects.

Chapter 2 is focused on giving a brief foreword about the conditions of the energy markets worldwide. Also, it provides a general picture of the Latin American region in economical and social terms.

Chapter 3 covers topics such as the definition of biofuels and their potential sources. Besides, the chapter explores alternative biofuels production pathways and their energetic balance. It finalises with a global portrait of the biofuel production and consumption nowadays and the perspectives for the future.

Chapter 4 reviews the Brazilian case study considering mainly its historical development and socio-economical dimensions.

Chapter 5 includes an analysis of relevant aspects of the bioenergy development in the Latin America and the Caribbean countries such as; particular drivers derived from their energetic mix, regional and local potential, policy implementation and current production. Chapter 6 provides a glimpse on the opportunities generated by the biofuel industry expansion such as GHG reduction potential, contribution to the energy security and rural development with a specific focus on the region under study.

Chapter 7 on the other hand focuses on the potential risks such as impacts on food prices and security, biodiversity loss and water scarcity aggravation.

Chapter 8 provides a discussion about the conflicting issues handled on Chapters 6 and 7. Chapter 9 covers the conclusions derived from the discussion held on previous chapters. Chapter 10 finalizes the research with some reflections about issues that need further exploration and research in the short and medium run.

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1.6 RESEARCH METHODOLOGY

Information has been sourced from books, recent news, journals, government agencies, trade associations, industry news and international electronic libraries. Scientific articles were corroborated with other sources, in order to create a richer picture of the events happening in this extent.

The methodology of this research work was based on the assessment and integration of divergent points of view coming from different stakeholders for better understand their concerns and the specific roles they can play in the implementation of solutions.

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2. GLOBAL ENERGETIC OVERVIEW

According to BP’s Statistical Review of World Energy (2007) during the last 10 years there have been significant changes in supply and demand conditions of the energy markets. Topics such as: the availability of energy to enable economic growth for a rising global population and the changing composition of the available fuel mix had remained at the centre of attention. High prices for fossil fuels, combined with political interest, encouraged the rapid growth of renewable energy sources, but this growth starts from a very small base.

The greatest challenge facing the energy sector today is how to meet rising demand for energy, whilst at the same time reducing the emissions of greenhouse gases due to the climate change recognition in the political and scientific sphere.

In 2007 BP suggested that growth in global energy consumption slowed, despite stronger economic growth: World primary energy consumption increased by 2.4%, down from 3.2% in 2005 and just above the last 10-year average.

Fig. 1 World energetic consumption (1981-2006)

Source: BP. Statistical Review of World Energy, June 2007

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It was also pointed out that growth slowed for every fuel except nuclear power. BP (2007) also suggested that during 2006 oil was the slowest growing fuel, while coal was the fastest growing. Although oil remains the world’s leading energy source, it has lost market share to coal and natural gas in the past decade.

In spite of this, oil remains the leading energy source in all regions except Asia Pacific and Europe and Eurasia. Coal dominates in the Asia Pacific region, while natural gas is the leading fuel in Europe and Eurasia. The Asia Pacific region accounted for two thirds of global energy consumption growth last year (BP 2007).

Fig. 2 Regional consumption pattern (2006)

Source: BP. Statistical Review of World Energy, June 2007

Hydrocarbons’ availability concerns and the crucial interest on guarantying energy security whilst reducing GHG emissions; had contributed to the growing enthusiasm about biofuels around the world.

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2.1 LATIN AMERICA AND THE CARIBBEAN: REGIONAL PROFILE

Latin America and the Caribbean include the island nations of the Caribbean Sea, Mexico, Central America, and South America. According to the UNCCD (2008) the population of Latin America and the Caribbean has increased dramatically over the last decades. From 1950 to 2008, it increased from 166 million 465 million inhabitants in which around 110 million live below the poverty line. Another important change in the population of the region is that it has rapidly moved to the urban areas. In LAC over 75% of the population of the region lived in cities in 2000. Especially massive ones are Mexico City (19.2 million people in 2005) and São Paulo (10.9 million people). Thinkquest (2008) suggested that urbanization has affected land usage, the level of natural resource depletion, and has created waste.

The World Bank (2008) pointed out that the LAC region and Sub Saharan Africa are the world’s most unequal region in terms of income distribution. The richest 20 percent receive 57 percent of the total, while the poorest consumes receive less than 3 percent. Most of inequalities between individuals can be attributed to inequalities observed within countries. In contrast, differences in average per capita incomes or consumption across countries are relatively small.

Economic overview

According to US Aid (2008) following the economic crises of the 1980s, economic activity has accelerated, but much of it is in the informal sector. It was also mentioned that individuals and families face increasing job insecurity, lower wages and a reduction in essential social services.

US Aid (2008) also noted that the change from military to civilian regimes throughout the

region and the devolution of powers to local authorities have given impetus to grass-roots and local initiatives, creating a climate for a diverse network of local and national non-governmental organizations and associations. Increasingly, local and municipal authorities are subject to election rather than appointment by central governments or parties, increasing their accountability and responsiveness to local populations.

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2.1.1 NATURAL RESOURCES

Land

According to the World Bank (2008) the region has the world’s largest reserves of arable land. Nevertheless, unplanned expansions of cities, erosion and changes in agricultural practices have contributed to the loss of once productive agricultural land. Long extensions of land have been degraded, mainly due to erosion caused by non-sustainable land use, nutrient depletion, chemical pollution, overgrazing and deforestation.

Water

The UNCCD (2008) suggested that the region under study has the greatest water resources per person (24.5 thousand cubic meters) and uses only 2 percent of that each year (South Asia, for instance uses 52 percent of its water resources in a year). Nevertheless, a large portion of cities' solid waste, industrial waste and sewage goes untreated, contaminating water supplies; cities like Lima and Mexico City which depend on wells are especially burdened (US Aid 2008). It was also noted that water plays an important role in generating electricity in the region since in 2005 hydropower generated 58 percent of the region’s electricity—higher than any other region. The region’s reliance on renewable energy, and a shift from oil to gas to generate electricity, has contributed to slowing the growth of carbon dioxide emissions.

Biodiversity

Of the top ten countries in the world in terms of biodiversity, called the ecological mega- diversity countries, five are in Latin America. These include Brazil, Colombia, Ecuador, Mexico, and Peru. Latin America is home to 40% of all the species found in tropical forests throughout the world. In fact, Colombia alone has 10% of the plant and animal species in the world (Thinkquest 2008).

Further features

According to the UNCCD (2008) even when Latin America and the Caribbean is a region well known for its rain forests, it is actually about one-quarter desert and drylands (20,533,000 km2). The hyper-arid deserts of the Pacific coast stretch from southern Ecuador, the entire

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Peruvian shoreline and northern Chile. Further inland, at altitudes of 3,000-4,500 meters, high and dry plains (Altiplano) of the Andean mountains cover large areas of Peru, Bolivia, Chile, and Argentina. Besides, large parts of Colombia and Venezuela are highly degraded.

In Dominican Republic, Cuba, Haiti and Jamaica, there are arid zones, as erosion and water shortages are noticeably intensifying in the Eastern Caribbean. Most of Mexico is arid and semi- arid, mainly in the north. Land degradation and severe droughts make the Central American countries vulnerable to extreme events, delaying their sustainable development.

It was also mentioned that poverty and pressure on land resources are causing land degradation in many of these areas.

The UNCCD (2008) strongly emphasized the need for sustainable development in the LAC region. Unsustainable practices including excessive irrigation and inappropriate agricultural practices, inadequate legal issues, inappropriate use of soil, fertilizers and pesticides, overgrazing, and intensive exploitation of forests. Frequent droughts and forest fires along with these practices lead to land degradation. Indeed, the sharp losses of ecosystem productivity reduce overall economic productivity and livelihoods.

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3. BIOFUELS AND THEIR PRODUCTION

3.1 DEFINITION OF BIOFUELS

According to the IEA (2004) either in liquid form such as fuel ethanol or biodiesel, or gaseous form such as biogas or hydrogen, biofuels are simply transportation fuels derived from biological (e.g. agricultural) sources. The NNEC et al. (2007) suggested that contrary to fossil fuels,

biomass 1 can, at least in principle, be replaced in a somewhat brief time period.

The present research focuses on liquid biofuels, because they are the fastest growing bioenergy sector and because countries from Latin America and the Caribbean benefit from favourable conditions for their production and future expansion, as it will be discussed in Chapter 5.

An additional cause for stressing liquid biofuels is that, for the moment, they are obtained mainly from agricultural crops, which can as well be used for food and animal feed, and hence could have direct impacts on food security, a core concern of the present paper.

According to NNEC et al. (2007) ethanol and biodiesel are the most widespread liquid biofuels. Ethanol is an alcohol made by fermenting biomass. Currently, ethanol is made from starches (such as corn-based ethanol) and sugars (such as sugarcanebased ethanol). Nevertheless, researchers are also looking into making ethanol from cellulose, the fibrous material that makes up the bulk of most plant matter. Ethanol is mostly used as blending agent with gasoline to increase octane and reduce vehicle emissions. On the other hand the biodiesel is made by combining alcohol (usually methanol or ethanol) with vegetable oil (mostly soy oil), animal fat, or used cooking grease. Other vegetable oils, including rapeseed, mustard, canola, and sunflower can also be used to produce

1 Biomass can be defined as any organic matter that is available on a renewable or recurring

basis, including agricultural crops and trees, wood and wood wastes and residues, plants

(including aquatic plants), grasses, residues, fibers, and animal wastes, municipal wastes, and

other waste materials (Biomass Research and Development 2000).

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biodiesel. Like ethanol, biodiesel can be used as an additive to reduce vehicle emissions or in its pure form as an alternative fuel for diesel engines.

3.1.1 SOURCES OF BIOFUELS

According to the IEA (2004) several sources can be used in order to produce biofuels:

N Cereals, grains, sugar crops and other starches can fairly easily be fermented to produce

ethanol, which can be used either as a motor fuel in pure (“neat”) form or as a blending component in gasoline.

N Oil-seed crops (e.g. rapeseed, soybean and sunflower) can be converted into methyl esters,

a liquid fuel which can be either blended with conventional diesel fuel or burnt as pure biodiesel.

N Cellulosic materials, including grasses, trees, and various waste products from crops, wood

processing facilities and municipal solid waste, can also be converted to alcohol but the process is more complex relative to processing sugars and grains. Techniques are being developed, however, to more effectively convert cellulosic crops and crop wastes to ethanol.

N Organic waste material can also be converted into energy forms which can be used as

automotive fuel: waste oil (cooking oil) into biodiesel; animal manure and organic household wastes into biogas (methane); and agricultural and forestry waste products into ethanol. Raw materials for these processes are generally low cost. Converting organic waste material to fuel can also diminish waste management problems.

3.1.2 ALTERNATIVE BIOFUELS PRODUCTION PATHWAYS

Ethanol Production - First Generation

According to the IEA (2004) ethanol can be produced from any biological feedstock that contains appreciable amounts of sugar or materials that can be converted into sugar such as starch or cellulose. Sugar beets and sugar cane are obvious examples of feedstock that contain sugar. Corn, wheat and other cereals contain starch (in their kernels) that can relatively easily be converted into sugar. Similarly, trees and grasses are largely made up of cellulose and

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hemicellulose, which can also be converted to sugar, though with more difficulty than conversion of starch.

According to Rothkopf (2007) there are a variety of methods that can produce ethanol. The initial steps of each method tend to be feedstock-specific, but in all processes, the starch is extracted, fermented and distilled into ethanol. These key steps in the feedstock-to-ethanol conversion process, by feedstock type, are shown in figure 3 and discussed below.

Fig. 3 Ethanol Production steps by feedstock and conversion technique

Source: IEA (2004)

Rothkopf (2007) offered a comprehensive description of the steps of the ethanol production process as follows:

Sugarcane Ethanol

The process of producing ethanol from sugarcane entails:

1) Extraction – the sugarcane must be broken up to make the juice more easily accessible; this is typically accomplished using a roller press. The juice is then collected, and the leftover bagasse,

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comprised mostly of sugarcane stalks and water, can be burned in boilers to co-generate power for the processing plant. Additional steps such as imbibation or diffusion can maximize extraction. These steps involve extracting the remaining sucrose by adding water to the bagasse.

2) Purification – there are a number of impurities contained in the juice once it is extracted, including dirt and small pieces of bagasse. Once extracted, the juice is typically filtered through a variety of methods such as straining, sedimentation, and centrifuge force. It is then chemically treated, heated and put through a process of evaporation to extract excess water.

3) Saccharification – lime is added to the juice mixture and the liquid is then heated and cooled again. After this phase, the juice is pasteurized and sterilized.

4) Fermentation – the sugars are transformed into ethanol and carbon dioxide through a biochemical process where yeast is added to ferment the sugars. This process includes several stages of fermentation and can last from 4-12 hours. Afterwards, the yeast is removed from the ethanol by centrifuge.

5) Distillation – the mixture now contains 7-10% alcohol and unfermented solids. It is processed in a series of distillation columns to remove the unfermented matter.

The ethanol leaves through the top of the final column with strength of 96%, and the leftover phlegm leaves through the bottom of the final column. At this stage, ethanol contains some small percentage of water, typically 4%, and is called hydrous ethanol.

6) Dehydration – to achieve maximum strength ethanol, the 96% mixture is dehydrated using benzol, which is later removed, leaving a mixture of 99.7% ethanol, called anhydrous ethanol. The quality of the cane determines the amount of juice extracted. For good-quality sugarcane, 100 kilograms of crop can yield up to 50 kilograms of juice made up of 22% sugar, using the three-roller method. Sugarcane that has been harvested early would typically yield less—roughly

40 kilograms —with a sugar content of 17% (Rothkopf 2007).

The IEA (2004) also noted that in the sugar cane process, the crushed stalk of the plant, the “bagasse”, consisting of cellulose and lignin, can be used for process energy in the manufacture of ethanol. This is one reason why the fossil energy requirements and greenhouse gas emissions of cane-to-ethanol processes are relatively low (See Chapter 6-Biofuels opportunities). On the other hand, the steps to produce ethanol from corn were also detailed by Rothkopf (2007) as follows:

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Corn Ethanol Corn can be processed through either dry or wet milling. The dry milling process includes the following steps:

1) Milling – the feedstock is ground into a fine powder called meal.

2) Liquefaction – the meal is mixed with water and an enzyme called alpha-amylase. It is then passed through a cooker to liquefy the starch.

3) Saccharification – the liquid starch, or mash, is cooled and a second enzyme called gluco- amylase is added to convert the liquid starch into dextrose, a fermentable sugar.

4) Fermentation – a biochemical process, yeast is added to the mash to ferment the dextrose into ethanol and carbon dioxide. This process entails several stages of fermentation and can last up to

48 hours.

5) Distillation – the fermented mash, now called beer and containing roughly 10% alcohol and unfermented solids left over from the feedstock and yeast, is processed in a series of distillation columns to remove the unfermented matter. The alcohol leaves through the top of the final column with a strength of 96% (hydrous ethanol), and the leftover residue, usually called stillage, leaves the bottom of the final column and is moved to a co-product processing area.

6) Dehydration – The remaining water is removed from the alcohol, often using a molecular sieve, and what is left is pure at nearly 200 proof (anhydrous ethanol).

7) Denaturing – a small amount of gasoline is added to the ethanol, usually 2-5%, making it ready for use as fuel as well as unfit for human consumption.

Distiller’s grain and carbon dioxide are the two main co-products of ethanol production. Distiller’s grain can be used as feed for livestock, and carbon dioxide can be compressed and sold for use in other industries.

In the wet milling process, the fiber, germ (oil) and protein are removed from the starch so that it can be fermented into ethanol. The first step is what differentiates wet from dry milling:

1) Steeping/ Separation – the feedstock is steeped in water and sulfur dioxide for 24 to 36 hours to separate the starch and protein connections. The corn is then ground to break apart the germ and kernel.

For corn, dry milling is more cost effective than wet milling, and it requires less equipment. Nevertheless, Rothkopf (2007) pointed out that an advantage of wet milling is that valuable co-

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