Handbook of Cellulosic Ethanol E-Book

Ananda S. Amarasekara

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Veröffentlichungsjahr: 2013

Beschreibung

Comprehensive coverage on the growing science and technology of producing ethanol from the world's abundant cellulosic biomass

The inevitable decline in petroleum reserves and its impact on gasoline prices, combined with climate change concerns, have contributed to current interest in renewable fuels. Bioethanol is the most successful renewable transport fuel—with corn and sugarcane ethanol currently in wide use as blend-in fuels in the United States, Brazil, and a few other countries. However, there are a number of major drawbacks in these first-generation biofuels, such as their effect on food prices, net energy balance, and poor greenhouse gas mitigation. Alternatively, cellulosic ethanol can be produced from abundant lignocellulosic biomass forms such as agricultural or municipal wastes, forest residues, fast growing trees, or grasses grown in marginal lands, and should be producible in substantial amounts to meet growing global energy demand.

The Handbook of Cellulosic Ethanol covers all aspects of this new and vital alternative fuel source, providing readers with the background, scientific theory, and recent research progress in producing cellulosic ethanol via different biochemical routes, as well as future directions. The seventeen chapters include information on:

• Advantages of cellulosic ethanol over first-generation ethanol as a transportation fuel
• Various biomass feedstocks that can be used to make cellulosic ethanol
• Details of the aqueous phase or cellulolysis route, pretreatment, enzyme or acid saccharification, fermentation, simultaneous saccharification fermentation, consolidated bioprocessing, genetically modified microorganisms, and yeasts
• Details of the syngas fermentation or thermochemical route, gasifiers, syngas cleaning, microorganisms for syngas fermentation, and chemical catalysts for syngas-to-ethanol conversion
• Distillation and dehydration to fuel-grade ethanol
• Techno-economical aspects and the future of cellulosic ethanol

Readership

Chemical engineers, chemists, and technicians working on renewable energy and fuels in industry, research institutions, and universities. The Handbook can also be used by students interested in biofuels and renewable energy issues.

Leseprobe

Contents

Cover

Half Title page

Title page

Copyright page

Preface

Part 1: Introduction to Cellulosic Ethanol

Chapter 1: Renewable Fuels

1.1 Introduction

1.2 Renewable Energy

1.3 Biofuels

1.4 Renewable Energy in the United States

1.5 Renewable Fuel Legislature in the United States

References

Chapter 2: Bioethanol as a Transportation Fuel

2.1 Introduction — History of Bioethanol as a Transportation Fuel

2.2 Alcohol Fuels

2.3 Fuel Characteristics of Ethanol

2.4 Corn and Sugarcane Ethanol

2.5 Advantages of Cellulosic Ethanol

References

Chapter 3: Feedstocks for Cellulosic Ethanol Production

3.1 Introduction

3.2 Cellulosic Ethanol Feedstock Types

3.3 Potential of Agricultural Wastes

3.4 Major Crop Residue Feedstock

3.5 Forestry Residue, Logging and Mill Residue

3.6 Grass Feedstocks

3.7 Purpose-Grown Trees as Feedstock

3.8 Municipal and Other Waste as Feedstock for Cellulosic Ethanol

References

Part 2: Aqueous Phase Biomass Hydrolysis Route

Chapter 4: Challenges in Aqueous-Phase Biomass Hydrolysis Route: Recalcitrance

4.1 Introduction – Two Ways to Produce Cellulosic Ethanol

4.2 Challenges in Aqueous-Phase Biomass Hydrolysis

4.3 Structure of Plant Cells and Lignocellulosic Biomass

4.4 Major Components of Lignocellulosic Biomass

4.5 Cellulose Recalcitrance

References

Chapter 5: Pretreatment of Lignocellulosic Biomass

5.1 Introduction

5.2 Different Categories of Pretreatment Methods

5.3 Physical Pretreatment

5.4 Physicochemical Pretreatment

5.5 Chemical Pretreatment

5.6 Biological Pretreatment

5.7 Conclusion

References

Chapter 6: Enzymatic Hydrolysis of Cellulose and Hemicellulose

6.1 Introduction

6.2 Enzymatic Actions on Lignocellulosic Biomass

6.3 Enzymatic Hydrolysis of Cellulose

6.4 Enzymatic Hydrolysis of Hemicellulose

6.5 Future Directions in Enzymatic Cellulose Hydrolysis Research

References

Chapter 7: Acid Hydrolysis of Cellulose and Hemicellulose

7.1 Introduction

7.2 Concentrated Acid Hydrolysis

7.3 Dilute Acid Hydrolysis

7.4 Ionic Liquid-Based Direct Acid Hydrolysis

7.5 Solid Acid Hydrolysis

References

Chapter 8: Fermentation I – Microorganisms

8.1 Introduction

8.2 Detoxification of Lignocellulosic Hydrolyzate

8.3 Separate Hydrolysis and Fermentation (SHF)

8.4 Microorganisms Used in the Fermentation

8.5 Fermentation Using Yeasts

8.6 Fermentation Using Bacteria

8.7 Simultaneous Saccharification and Fermentation (SSF)

8.8 Immobilization of Yeast

References

Chapter 9: Fermentation II – Fermenter Configuration and Design

9.1 Introduction

9.2 Batch Fermentation

9.3 Fed-Batch Fermentation

9.4 Continuous Fermentation

9.5 New Directions in Fermenter Configuration and Design

References

Chapter 10: Separation and Uses of Lignin

10.1 Introduction

10.2 Structure of Lignin

10.3 Separation of Lignin in the Cellulosic Ethanol Process

10.4 Physical and Chemical Properties of Lignin

10.5 Applications of Lignin

References

Part 3: Biomass Gasification Route

Chapter 11: Biomass Pyrolysis and Gasifier Designs

11.1 Introduction

11.2 Chemistry of the Conversion of Biomass to Syngas

11.3 Classifications of Biomass Gasifiers

11.4 Fixed-Bed Gasifier

11.5 Fluidized-Bed Gasifier

11.6 Bubbling Fluidized-Bed (BFB) Gasifier

11.7 Circulating Fluidized-Bed (CFB) Gasifier

11.8 Allothermal Dual Fluidized-Bed (DFB) Gasifier

11.9 Entrained-Flow Gasifier

11.10 Syngas Cleaning

11.11 Tar Control and Treatment Methods

References

Chapter 12: Conversion of Syngas to Ethanol Using Microorganisms

12.1 Introduction

12.2 Metabolic Pathways

12.3 Microorganisms Used in Syngas Fermentation

12.4 Biochemical Reactions in Syngas Fermentation

12.5 The Effects of Operation Parameters on Ethanol Yield

12.6 Syngas Fermentation Reactors

12.7 Industrial-Scale Syngas Fermentation and Commercialization

References

Chapter 13: Conversion of Syngas to Ethanol Using Chemical Catalysts

13.1 Introduction

13.2 Homogeneous Catalysts

13.3 Introduction to Heterogeneous Catalysts

13.4 Heterogeneous Catalyst Types

13.5 Rhodium-Based Catalysts

13.6 Copper-Based Modified Methanol Synthesis Catalysts

13.7 Modified Fischer-Tropsch Type Catalysts

13.8 Molybdenum-Based Catalysts

13.9 Catalyst Selection

References

Part 4: Processing of Cellulosic Ethanol

Chapter 14: Distillation of Ethanol

14.1 Introduction

14.2 Distillation of the Beer

14.3 How Distillation Works

14.4 Conventional Ethanol Distillation System

14.5 Steam Generation for Distillation Process

14.6 Studies on Development of Hybrid Systems for Ethanol Distillation

References

Chapter 15: Dehydration to Fuel Grade Ethanol

15.1 Introduction

15.2 Dehydration Methods

15.3 Adsorption Method

15.4 Azeotropic Distillation Method

15.5 Extractive Distillation Methods

15.6 Membrane-Based Pervaporation Methods

15.7 Other Dehydration Methods

15.8 Comparisons of Common Dehydration Methods

References

Part 5: Fuel Ethanol Standards and Process Evaluation

Chapter 16: Fuel Ethanol Standards, Testing and Blending

16.1 Introduction

16.2 Fuel Grade Ethanol Standards in the United States

16.3 Quality Assurance and Test Methods

16.4 European Fuel Ethanol Standards

16.5 Material Safety Data Sheet (MSDS) for Denatured Fuel Ethanol

16.6 Gasoline Ethanol Blends

16.7 Engine Performance Using Gasoline Ethanol Blends

References

Chapter 17: Techno-Economic Analysis and Future of Cellulosic Ethanol

17.1 Introduction

17.2 Techno-Economic Aspects of Biomass Hydrolysis Process

17.3 Techno-Economic Aspects of Biomass Gasification Process

17.4 Comparison of Biomass Hydrolysis and Gasification Processes

17.5 Some Cellulosic Plants around the World

17.6 Challenges in Cellulosic Ethanol

17.7 Future Prospects of Cellulosic Ethanol

References

Appendix 1: Material Safety Data Sheet

Index

Handbook of Cellulosic Ethanol

Scrivener Publishing100 Cummings Center, Suite 541JBeverly, MA 01915-6106

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Preface

The inevitable decline in petroleum reserves and the rise in demand for oil from rapidly growing economies have caused soaring oil prices, and coupled with climate change concerns have contributed to the current interest in renewable energy resources. In some parts of the world this interest has resulted in the introduction of legislations promoting the use of renewable energy resources and increasing government incentives for commercialization of renewable energy technologies. Development of science and technologies for efficient conversion of lignocellulosic biomass to renewable liquid transportation fuels has become one of the high priority research areas of the day, and bioethanol is the most successful biofuel to date. Corn- and sugarcane-derived first generation bioethanol is currently in wide use as a blend-in fuel in gasoline sold in the United States, Brazil, and in a few other countries. However, there are a number of major drawbacks to these first generation fuels such as the effect on food prices as traditional food resources are utilized as raw materials, net energy balance, and poor greenhouse gas mitigation.

Cellulosic ethanol is a second generation biofuel produced from agricultural wastes, grasses, municipal wastes, and other feedstocks that do not double as food, so unlike traditional corn-based ethanol, it promises to avoid encroaching upon and destabilizing the human food supply. In addition, cellulosic ethanol can be produced from a variety of abundant lignocellulosic biomass feedstocks, and should be able to be produced in substantial amounts to meet the growing global energy demand. There are two fundamental routes to produce cellulosic ethanol from renewable biomass: the aqueous-phase biomass saccharification-fermentation route, and thermochemical gasification route. The thermochemical route can be divided into two paths as syngas produced from biomass can be converted to ethanol by chemical or enzymatic methods.

This handbook is a comprehensive up-to-date guide to cellulosic ethanol, divided into five parts: introduction to cellulosic ethanol, aqueous-phase biomass hydrolysis route, biomass gasification route, processing of fuel grade ethanol, and techno-economical evaluation of the processes. The first part covering Chapters 1 to 3 introduces the reader to cellulosic ethanol, presenting the advantages over first generation corn or sugarcane ethanol. In the United States, the gradual transition to renewable energy sources is supported by a series of legislations and government incentives, and these aspects of bioethanol are also discussed in this part. Then, various types of cellulosic ethanol feedstocks are presented in the third chapter, including agricultural wastes, fast growing grasses such as switchgrass and trees like poplar, forestry residues and municipal wastes.

The second part of the book covering Chapters 4 to 10 presents the cellulolysis processes or aqueous-phase biomass saccharification-fermentation route. Chapters 4 and 5 detail the challenges in biomass saccharification, or recalcitrance, as well as various pretreatment techniques such as physical, physicochemical, chemical, and biological pretreatments, and applications to different feedstocks. Chapter 6 covers the enzymatic saccharification, including cellulases, hemicellulase families, mechanisms, enzyme preparation methods, and immobilization of enzymes. Chapter 7 is dedicated to acid hydrolysis, or direct saccharification, using various acid catalysts: concentrated, dilute mineral acids, progress in ionic liquid-based systems, acid group functionalized ionic liquids, and solid acids. Fermentation of the sugar solution to “beer” is presented in Chapters 8 and 9. The microorganisms used in the fermentations, including recent advances in genetic modifications of microorganisms, separate hydrolysis fermentation (SHF), simultaneous saccharification and fermentation (SSF), consolidated bio-processing (CBP), and surface-engineered and immobilized yeasts are covered in detail in Chapter 8. Fermentation configurations and engineering aspects of fermenter design are presented in Chapter 9. In addition, separation and utilization of lignin byproduct is also covered in this section, under Chapter 10, introducing the total bio-refinery concept.

The third part of the book (Chapters 11–13) is dedicated to the biomass gasification route, which is an alternative approach for producing ethanol from lignocellulosic biomass. Pyrolysis chemistry, gasifier designs, and syngas cleaning are covered in Chapter 11, whereas the conversion of syngas to ethanol using microorganisms and their metabolic pathways are presented in Chapter 12. Syngas produced from biomass can be transformed into ethanol using metal catalysts such as Rh-, Mo- or Cu-based systems as well, and this route is presented in Chapter 13.

Processing of ethanol produced thorough various paths is presented in Part 4 of the book. Concentration of ethanol to approximately 90% ethanol by distillation is the first step in purification of ethanol. Technologies used in the current first generation ethanol industry for distillation of the “beer” to an azeotrope mixture, and then dehydration to > 99.5% fuel grade ethanol, are adoptable to cellulosic ethanol as well. Engineering aspects of the industrial three column distillation set up and recent technological advances like pervaporation are discussed in Chapters 14 and 15. Part 5 provides the details of fuel ethanol standards and process evaluation. Fuel grade ethanol standards in the US and EU, testing methods, and quality control are some of the sections in Chapter 16. Finally, the techno-economic aspects of cellulosic ethanol, a list of current and under-construction cellulosic ethanol plants around the world as of June, 2013, and the future prospects of cellulosic ethanol are presented in Chapter 17.

It is my great pleasure to thank Scrivener Publishing and John Wiley & Sons for kindly agreeing to publish this book. Finally, I wish to thank my wife Preethika, daughter Hiruni, and son Hasun for their love, support, encouragement, and patience during the writing of this book.

Ananda S. AmarasekaraJune, 2013

Part 1

Introduction to Cellulosic Ethanol

Chapter 1

Renewable Fuels

1.1 Introduction

Since the beginning of civilization on earth, humans have used biomass for many of their energy needs such as cooking, heating dwellings, lighting, firing clay pots, and processing metals. The industrial revolution, leading to the development of the internal combustion engine for transportation and coal power plants for electricity generation have caused a rapid shift in our energy dependence from renewable resources to non-renewable fossil fuel resources. The processes of industrialization and continuous economic development are driven by energy consumption. The global demand for energy is expected to increase at a faster rate in upcoming years due to rapidly developing economies and partly due to the exponential growth in the world’s population.

The energy demand predictions for the Organization for Economic Cooperation and Development (OECD) nations as well as for non-OECD nations are available in the International Energy Outlook report of the U.S. Department of Energy. The world energy consumption from 1990 with predictions till 2035 is shown in the bar graph in Figure 1.1 [1]. This study forecasts that total world energy use will rise to 619 quadrillion BTU (British thermal unit) in 2020, and 770 quadrillion BTU in 2035 from the 2008 value of 505 quadrillion BTU. Furthermore, much of the growth in energy consumption is expected to occur in countries outside the Organization for Economic Cooperation and Development (non-OECD nations) where demand is driven by strong long-term economic growth. Energy use in non-OECD nations increases by 85 percent in the reference case, as compared with an increase of 18 percent for the OECD economies as shown in Figure 1.1 [1].

Figure 1.1 World energy consumption from 1990–2035 (quadrillion BTU) from International Energy Outlook report released in 2011 [1].

At a time of rapid increase in global energy consumption, energy sources are a critical term in the energy equation. As of 2012, more than 80% of the world’s energy needs are fulfilled by fossil fuels and the contributions to global energy demand from different resources are presented in the Global Renewable Energy Share Report; the current shares of principal resources are shown in the pie chart in Figure 1.2 [2]. Total renewable energy share is 16.7%, and these sources can be divided into two groups: traditional renewables and modern renewables. On the global scale, the share of traditional renewables is slightly higher than all the combined modern renewables. Traditional biomass energy sources such as firewood, which are used primarily for cooking and heating in rural areas of developing countries, could be considered renewable. These traditional renewables account for approximately 8.5% of total final energy consumption. Modern renewable energy is dominated by hydropower for electricity generation and accounts for 3.3%; heat generation using modern biomass-derived fuels such as biogas, geothermal and solar heating accounts for another 3.3%. Biomass-derived transportation biofuel such as bioethanol and biodiesel supplies only 0.7% of the current global energy requirement.

Figure 1.2 Renewable energy share of global final energy consumption, from Renewable Energy 2012 Global status report, Paris [2].

While fossil fuels have become the world’s main energy resource and are at the center of global energy demands, its reserves are limited. There are varying estimates of fossil fuel reserves on earth. In spite of all the recent advances in oil exploration technologies, the frequency of new oil and coal discoveries has rapidly diminished in the last twenty years. In cases like shale oil and tracking, much higher efforts and investments are required for extraction of fossil fuel from earth. As a finite resource depletion of petroleum reserves is inevitable, limitations in the supply have resulted in a rapid increase in fuel prices around the globe after the 1970s.

However, according to the World Energy Outlook 2012 predictions, a steady increase in hydropower and rapid expansion of wind and solar power has cemented the position of renewables as an indispensable part of the global energy mix. By 2035, renewables are expected to account for almost one-third of total electricity output [3]. Solar power is expected to grow more rapidly than any other renewable energy technology. Furthermore, in accordance with International Energy Agency (IEA) 2012 predictions, renewables will become the world’s second largest source of power generation by 2015.

Modern renewable energy can substitute for fossil fuels in four distinct markets: power generation, heating and cooling, transport fuels, and rural/off-grid energy services. During the last decade, total global installed capacity of many renewable energy technologies grew at very rapid rates. Solar photovoltaics (PV) grew the fastest of all renewable technologies during this period, with operating capacity increasing an average of 58% annually. It was followed by concentrating solar thermal power (CSP), which increased almost 37%, growing from a small base and wind power, which increased by 26%. The growth of liquid biofuels has been mixed in recent years, with biodiesel production expanding in 2011, and ethanol stable or down slightly compared with 2010. Hydropower and geothermal power are growing globally at rates of 2–3% per year, making them more comparable with global growth rates for fossil fuels. However, in several European countries the growth in these and other renewable energy technologies far exceeds the global average [2].

1.2 Renewable Energy

A renewable energy source can be defined as an energy source that is continually replenished, is available over the long term at a reasonable cost that can be used with minimum environmental impacts, produces minimum secondary wastes, and is sustainable based on current and future economic and social needs. This definition of renewable energy resources includes many forms such as wind energy, solar energy, biofuels, geothermal energy, and ocean wave energy.

It is natural to believe that human civilization is not prepared to make sacrifices in the quality of life and inhibit energy consumption-driven growth due to the decline in finite fossil-fuel-based energy resources. Therefore, humans who have already come this far are smart enough to realize that renewable energy is the alternative to finite fossil energy sources. In addition to this, there are many encouraging points for the development and use of renewable energy sources like diversity in energy supply options, both for developed and developing nations.

Except in the case of geothermal energy, the sun is the primary source of all renewable energy, and currently the total energy generating capacity of all energy conversion systems built by mankind amounts to about 14 TW (terawatt). In comparison to this, the solar input is extremely large, and the continuous solar input is equivalent to 90000 TW, of which about 1000 TW could in principle be captured for energy conversion to forms we can use [4]. Of course, there are significant losses due to poor conversion efficiencies and land use constraints that need to be taken into account, but even so, there should be sufficient raw energy from the sun to meet our needs many times over. The challenge is development of efficient green technologies. Energy scenarios are widely used to describe possible paths ahead and the sustainable growth scenario produced by Shell International in 1995 has been very influential. It suggested that, by around 2060, renewables sources could meet about half of the world’s total energy needs. Subsequent studies have suggested that in principle, by 2100, renewables could perhaps meet over 80% of global energy needs, assuming that they were seen as a priority for environmental reasons. Inevitably, long-term projections like this are very speculative. In 2012, modern renewables supplied around 8.2% of the world’s energy, which included about 3.3% provided by hydropower electricity. The contribution is expanding rapidly, stimulated by some quite demanding targets. For example, the European Union aims to have 12.5% of its electricity produced from renewable sources by 2020, with some member countries aiming for even higher targets. Denmark aims for 29%, Finland 21.7%, Portugal 21.5% and Austria 21.1%, and these figures exclude the contribution from large hydropower plants [2].

1.3 Biofuels

Biomass-derived fuels or biofuels are an important contributor in the modern renewables slice of the energy source distribution pie chart shown in Figure 1.2. The use of biogas in heating houses, biogas-derived syngas in electricity generation and transport biofuels are some of the major applications in this type of sustainable energy. Biofuels are produced from bio-based materials through various paths such as biochemical [5, 6], and thermochemical methods [7, 8]. In general the use of unprocessed biomass forms like firewood for heating or cooking purposes are not included in this group. Chemically, many forms of biofuels contain oxygen as one of the elements, whereas petroleum fuels are hydrocarbons free of oxygen. Another important difference is the sulfur level; all bio-fuels are very low in sulfur in comparison to petroleum fuels and many have low nitrogen levels as well.

1.3.1 Advantages of Biofuels

Common biofuels include bioethanol, biomethanol, vegetable oils, biodiesel, biogas, biosynthetic gas or biomass-derived syngas, bio-oil, bio-char, and bio-hydrogen. The benefits or advantages of biofuels can be broadly classified into three groups: economic, environmental, and energy security and these factors are outlined below [9,6].

Economic impacts:

Sustainability in relation to economic growth

Increased number of rural manufacturing jobs in biorefinery

Opportunity for certain developing countries to reduce their dependence on oil imports

Increased investments in plant and equipment

Fuel diversity

Agricultural development

International competitiveness, especially for developing countries with land resources

Environmental impacts:

Greenhouse gas reductions

Reduction of air pollution—bioethanol’s high oxygen content reduces carbon monoxide levels more than any other oxygenate

Biodegradability

Improved land and water use

Carbon sequestration

Energy security:

Supply reliability independent of international political climate

Ready availability

Ability to set domestic targets for production and markets

Domestic distribution

Renewability

In addition to these, there may be other socio-economic and environmental implications for developing countries to benefit from increased global demand for biofuels. In developed countries there is a growing trend towards employing modern technologies in large-scale production of biofuels. Furthermore, with recent advances like genetic manipulations of microorganisms, and efficient bioenergy conversions, biofuels are becoming cost competitive with fossil fuels [10].

1.3.2 Gaseous Biofuels

Biomass can be converted into gaseous and liquid fuels through thermochemical and biochemical routes. Some of the common gaseous biofuels are:

1.Biogas. This is the gas mixture produced by anaerobic digestion of biodegradable materials such as cow manure, sewage, municipal wastes, and plant materials. The major component in biogas is methane (CH4), which is about 60%, the remainder is carbon dioxide. In addition to this, small amounts of hydrogen sulfide and nitrogen are also found in this gaseous biofuel.

2.Biosynthetic gas or biomass-derived syngas. Gasification of lignocellulosic biomass under controlled conditions is used to produce syngas. This gaseous biofuel is a mixture of carbon monoxide, hydrogen and carbon dioxide. The syngas produced from biomass can be used directly as a fuel in gas turbines for electricity generation or as a transport fuel in internal combustion engines. Biomass-derived syngas can also be converted to ethanol by chemical and biochemical methods as well. Production of syngas and upgrading of syngas to bioethanol is described in Part 3 of this book.

3.Biohydrogen. This is the hydrogen produced from biomass resources. Several routes are currently under study for production of hydrogen, which include dark/photo fermentations [11, 12] and steam reforming of bio-oil [13].

1.3.3 Liquid Biofuels

Liquid biofuels fall into three general categories:

1. Bioalcohols

2. Vegetable oil- and algae-based biodiesel

3. Biomass-based hydrocarbon fuels or drop-in biofuels

The most commonly used liquid biofuels are bioethanol and biodiesel. Currently, bioethanol is produced primarily from corn and sugarcane. Biodiesel is made from virgin plant oils such as soybean oil, rapeseed oil, palm oil, and from algae. The amount of plant oil that can be harvested from these crops varies widely; some of the common crops under consideration for vegetable oil-based biodiesel, and oil yields per hectare, are shown in Table 1.1 [14]. In addition to this, used cooking oil and animal fats like chicken fat can also be used in the synthesis of biodiesel. Liquid biofuels have made a small but growing contribution to transport fuel usage worldwide, currently providing about 3% of global road transport fuels [2].

Table 1.1 Typical vegetable oil yields from the various biomasses [14].

Crop

Oil yield (Liters/ha)

Rubber seed

80–120

Corn

172

Soybean

446

Safflower

779

Chinese tallow

907

Camelina

915

Sunflower

952

Peanut

1059

Canola

1190

Rapeseed

1190

Castor

1403

Jatropha

1892

Karanj

2590

Coconut

2689

Oil palm

5950

These fuels are mainly used in ground transportation systems as blends with conventional fuels. A limited amount of biofuel is used by the marine transport sector, and interest is growing in the use of biofuels for aviation. Camelina-, Jatropha-, and algae-based bio oils are of primary interest in renewable aviation fuel research. Liquid biofuels derived from these oils have been tested as blend-in fuels with jet kerosene in commercial and demonstration flights. Ethanol is by far the most popular liquid biofuel and a comparison of biodiesel and bioethanol in primary feedstocks and production costs in different parts of the world are shown in Table 1.2.

Table 1.2 Estimated production costs (US $/Liter) of first generation renewable transportation fuels.

First generation liquid biofuel

Typical Feedstocks

Estimated Production Costs (US $/Liter)

Biodiesel

soy, rapeseed, palm, jatropha, waste vegetable oils, and animal fats

Range: 0.17–1.77

Argentina (soy): 0.42–0.91 USA (soy): 0.55–0.82 Indonesia / Malaysia / Thailand/Peru (Palm oil): 0.24–1.00

Ethanol

sugarcane, sugar beets, corn, cassava, sorghum, and wheat

Range: 0.20–1.02

Brazilian sugarcane: 0.68 (2011) US corn ethanol (dry mill) 0.40 (2010)

Notes: Costs are indicative of economic costs, levelized, and exclusive of subsidies or policy incentives [2].

Bioethanol and biodiesel are the two major liquid biofuels. There has been a gradual increase in the production of these fuels; global ethanol and biodiesel production in billon liters (BL) from 2000–2011 is shown in Figure 1.3. Bioethanol production has increased from 17 BL in 2000 to 86 BL in 2011, whereas biodiesel has increased from 0.8 to 21.4 BL during the same period [2]. Global production of fuel ethanol was down slightly in 2011, from 86.5 BL in 2010 to 86.1 BL in 2011. In 2011, the United States and Brazil accounted for 64% and 25% of global ethanol production, respectively, compared with 60% and 30% in 2010. Although global production was slightly down, in the United States bioethanol production reached a new high, exceeding 54 billion liters in 2011 [2].

Figure 1.3 Global ethanol and biodiesel production in billon liters (BL), 2000–2011 [2].

Brazil is the second largest fuel-grade ethanol producer in the world. Together, Brazil and the United States lead the industrial production of ethanol fuel, accounting for 88.8% of the world’s production in 2011. In 2011, Brazil produced 21.1 billion liters representing 24.9 percent of the world’s total ethanol used as fuel. However, fuel ethanol production in Brazil has declined recently due to several reasons like financial crisis, poor sugarcane harvests due to unfavorable weather and high world sugar prices. China is the world’s third largest ethanol producer with a production capacity of 2.1 billion liters in 2011, and is the largest ethanol producer in Asia. On a global scale. China is followed by Canada (1.8 billion liters), France (1.1 billion), and Germany (0.8 billion).

In contrast to ethanol, global biodiesel production continued to expand, increasing by almost 16% to 21.4 billion liters in 2011, compared with 18.5 billion liters in 2010. The United States saw a record year, with biodiesel production increasing by 159% to nearly 3.2 billion liters, mainly from soybeans. As a result, the United States surpassed the 2010 leaders Germany, Brazil, Argentina, and France, to become the world’s top producer. The dramatic increase in biodiesel production in the United States was due to a government mandate in mid 2010 that required refiners to blend 3.1 billion liters (800 million gallons) of biodiesel with diesel fuel in 2011 or face stiff daily fines. The EU remained the largest regional producer of biodiesel, but its total production declined by 6%, and the EU share of the world total was down from 53% in 2010 to 43% in 2011. Germany dropped from first to second place globally in biodiesel production, although its production increased by 18%. The other major biodiesel producers in 2011 were Argentina (2.8 billion liters), Brazil (2.7 billion liters), and France (1.6 billion liters).

Vegetable oils are unsatisfactory for direct use as fuel in an engine due to the higher level of viscosity, lower volatility, free fatty acid content and the matter of carbon deposits. These deficiencies considerably limit the use of raw oil as a direct substitute for diesel fuel [15]. Many technologies and methods have been tested to reduce the viscosity of raw vegetable oil. These include pyrolysis, catalytic cracking and trans-esterification with small alcohols like methanol or ethanol. Biodiesel blended or used to replace diesel is produced by trans-esterification of vegetable oil or waste fats, hence biodiesel can be defined as mono alkyl esters of fatty acids derived from vegetable oil or animal fats. Among many techniques, trans-esterification with methanol using sodium hydroxide as the catalyst is the most promising method for conversion of vegetable oils or waste fats to biodiesel. The reaction is normally carried out with a sequence of three consecutive reversible reactions [16]. In this process triglyceride is converted stepwise into diglyceride, monoglyceride, and finally to glycerol in which one mole of alkyl ester is formed in each step [17].

A number of researchers have discussed the advantages of biodiesel such as heat content, ready availability; also some disadvantages such as high viscosity, lower volatility, and the reactivity of unsaturated hydrocarbon chains [18–20]. Shahid and Jamal [21] have reviewed a wide range of vegetable oils such as sunflower oil, cottonseed oil, rapeseed oil, soybean oil, palm oil, and peanut oil for their usefulness in biodiesel production and blending biodiesel with petroleum diesel. They concluded that using a mixture of petroleum diesel and biodiesel at an 80:20 ratio (B20) was the most successful.

1.4 Renewable Energy in the United States

As in many other countries, renewable energy resources-based electricity dominated the renewable energy landscape in the United States, and accounted for 13.2% of the domestically produced electricity in 2012 [22]. The states of Iowa, North Dakota, and California each generate more than 10 percent of their electricity supply from wind power, solar power, and/or geothermal power. Renewable energy reached a major milestone in the first quarter of 2011, when it contributed 11.7 percent of total US energy production (2.245 quadrillion BTUs of energy), surpassing energy production from nuclear power (2.125 quadrillion BTUs) [22].

Since the energy crisis in the 1970s the cost of transportation fuels has increased at a higher rate than other energy needs and combined with environmental concerns has promoted renewable transportation fuels to the center of attention in renewable energy discussions. Most cars on the road today in the United States can run on blends of up to 10% ethanol without any modifications, and motor vehicle manufacturers already produce vehicles designed to run on much higher ethanol blends. Three big American automobile manufacturers, General Motors (GM), Ford, and Chrysler are among the automobile companies that sell “flexible-fuel” cars, trucks, and minivans that can use gasoline and ethanol blends ranging from pure gasoline up to 85% ethanol (E85). There were approximately 8.35 million E85 flex-fuel vehicles in the US in 2010 [23].

1.4.1 Federal Agencies Promoting Renewable Energy

In the United States several federal agencies are involved in promoting the gradual transition from fossil resources to renewable energy resources. The two main agencies include the U.S. Department of Energy and US Environmental Protection Authority. Under these organizations there are a number of sub-agencies and branches involved in renewable energy issues such as the US Energy Information Administration. The National Renewable Energy Laboratory (NREL) located in Golden, Colorado, is the U.S. Department of Energy’s primary national laboratory for renewable energy, energy efficiency research and development, according to their mission statement in the NREL website: http://www.nrel.gov/.

The NREL develops renewable energy and energy efficiency technologies and practices, advances related science and engineering, and transfers knowledge and innovations to address the nation’s energy and environmental goals. The NREL’s emphasis is on a comprehensive energy approach that encompasses the relationship among key systems:

Fuel production

Transportation

The built environment

Electricity generation and delivery

The NREL has adopted a system integration approach in order to accelerate the transformation of energy use and delivery systems in the United States. In addition, the US government’s commitment to a clean energy future is emphasized by government incentives and legislative actions like the Renewable Fuel Standards of Energy Independence and Security Act of 2007.

1.4.2 Incentives for Renewable Fuels

There are a number of incentives for production and utilization of renewable fuels, such as bioethanol and biodiesel, under the U.S. Department of Energy’s Energy Efficiency and Renewable Energy Directorate [24]. These incentives come in the form of tax credits, grants and loan guarantees. Some of the key incentives are outlined below.

1. Alternative Fuel Infrastructure Tax Credit

Fueling equipment for natural gas, liquefied petroleum gas (propane), electricity, E85, or diesel fuel blends containing a minimum of 20% biodiesel installed between January 1, 2006, and December 31, 2013, is eligible for a tax credit of 30% of the cost, not to exceed $30,000. Fueling station owners who install qualified equipment at multiple sites are allowed to use the credit towards each location. Consumers who purchased qualified residential fueling equipment prior to December 31, 2013, may receive a tax credit of up to $1,000. Unused credits that qualify as general business tax credits, as defined by the Internal Revenue Service (IRS), may be carried backward one year and carried forward 20 years.Point of Contact: U.S. Internal Revenue Service

2. Advanced Energy Research Project Grants

The Advanced Research Projects Agency - Energy (ARPA-E) was established within the U.S. Department of Energy with the mission to fund projects that will develop transformational technologies that reduce the nation’s dependence on foreign energy imports; reduce US energy related emissions, including greenhouse gases; improve energy efficiency across all sectors of the economy; and ensure that the United States maintains its leadership in developing and deploying advanced energy technologies. The ARPA-E focuses on various concepts in multiple program areas including, but not limited to, vehicle technologies, biomass energy, and energy storage. For more information, visit the ARPA-E website: https://arpa-e-foa.energy.gov/.Point of Contact: U.S. Department of Energy

3. Improved Energy Technology Loans

The U.S. Department of Energy (DOE) provides loan guarantees through the Loan Guarantee Program to eligible projects that reduce air pollution and greenhouse gases, and support early commercial use of advanced technologies, including biofuels and alternative fuel vehicles. The program is not intended for research and development projects. DOE may issue loan guarantees for up to 100% of the amount of the loan for an eligible project. For loan guarantees of over 80%, the loan must be issued and funded by the Treasury Department’s Federal Financing Bank. For more information, see the Loan Guarantee Program website.Point of Contact: U.S. Department of Energy

4. Advanced Biofuel Production Grants and Loan Guarantees

The Biorefinery Assistance Program (Section 9003) provides loan guarantees for the development, construction, and retrofitting of commercial-scale biorefineries that produce advanced biofuels. Grants for demonstration-scale biorefineries are also available. Advanced biofuel is defined as fuel derived from renewable biomass other than corn kernel starch. Eligible applicants include, but are not limited to, individuals, state or local governments, farm cooperatives, national laboratories, institutions of higher education, and rural electric cooperatives. The maximum loan guarantee is $250 million and the maximum grant funding is 50% of project costs. Funding for this program is subject to congressional appropriations through fiscal year 2013. For more information, see the Biorefinery Assistance Program website.Point of Contact: Office of Rural Development, Business and Cooperative Programs, U.S. Department of Agriculture

5. Advanced Biofuel Production Payments

Through the Bioenergy Program for Advanced Biofuels (Section 9005), eligible producers of advanced biofuels, or fuels derived from renewable biomass other than corn kernel starch, may receive payments to support expanded production of advanced biofuels. Payment amounts depend on the quantity and duration of production by the eligible producer; the net nonrenewable energy content of the advanced biofuel, if sufficient data is available; the number of producers participating in the program; and the amount of funds available. No more than 5% of the funds will be made available to eligible producers with an annual refining capacity of more than 150,000,000 gallons of advanced biofuel. Funding for this program is subject to congressional appropriations through fiscal year 2013. For more information, see the Bioenergy Program for Advanced Biofuels website and contact the appropriate State Rural Development Office.Point of Contact: Office of Rural Development, Business and Cooperative Programs, U.S. Department of Agriculture

6. Biodiesel Education Grants

Competitive grants are available through the Biodiesel Fuel Education Program (Section 9006) to educate governmental and private entities that operate vehicle fleets, the public, and other interested entities about the benefits of biodiesel fuel use. Eligible applicants are nonprofit organizations or institutes of higher education that have demonstrated knowledge of biodiesel fuel production, use, or distribution; and have demonstrated the ability to conduct educational and technical support programs. Funding for this program is subject to congressional appropriations through fiscal year 2013.

Point of Contact: Office of Rural Development, Business and Cooperative Programs, U.S. Department of Agriculture

7. Biomass Research and Development Initiative

The U.S. Department of Agriculture’s National Institute of Food and Agriculture, in conjunction with U.S. Department of Energy Office of Biomass Programs, provides grant funding for projects addressing research, development, and demonstration of biofuels and biobased projects and the methods, practices, and technologies for their production, under the Biomass Research and Development Initiative (Section 9008). The competitive award process focuses on three main technical areas: feedstock development; biofuels and biobased products development; and biofuels development analysis. Eligible applicants are institutions of higher learning, national laboratories, federal research agencies, private sector entities, and nonprofit organizations. The non-federal share of the total project cost must be at least 20%. Funding for this program is subject to congressional appropriations through fiscal year 2013. For more information, see the Biomass Research & Development website.

Point of Contact: Office of Rural Development, Business and Cooperative Programs, U.S. Department of Agriculture

8. Ethanol Infrastructure Grants and Loan Guarantees

The Rural Energy for America Program (REAP) provides loan guarantees and grants to agricultural producers and rural small businesses to purchase renewable energy systems or make energy efficiency improvements. Eligible renewable energy systems include flexible fuel pumps, or blender pumps, that dispense intermediate ethanol blends. The maximum loan guarantee is $25 million and the maximum grant funding is 25% of project costs. At least 20% of the grant funds awarded must be for grants of $20,000 or less. Funding for this program is subject to congressional appropriations through fiscal year 2013. For more information, see the REAP website.

Point of Contact: Office of Rural Development, Business and Cooperative Programs, U.S. Department of Agriculture

9. Biobased Transportation Research Funding

The Surface Transportation Research, Development, and Deployment (STRDD) Program funds activities that promote innovation in transportation infrastructure, services, and operations. A portion of the funding made available to the STRDD Program is set aside for the Biobased Transportation Research Program to carry out biobased research of national importance at research centers and through the National Biodiesel Board. For more information, see the STRDD Program website.

Point of Contact: Federal Highway Administration, U.S. Department of Transportation

10. Alternative Fuel and Advanced Vehicle Technology Research and Demonstration Bonds

Qualified state, tribal, and local governments may issue Qualified Energy Conservation Bonds subsidized by the U.S. Department of Treasury at competitive rates to fund capital expenditures on qualified energy conservation projects. Eligible activities include research and demonstration projects related to cellulosic ethanol and other non-fossil fuels, as well as advanced battery manufacturing technologies. Government entities may choose to issue tax credit bonds or direct payment bonds to subsidize the borrowing costs. For information on eligibility, processes, and limitations, contact local issuing agencies.

11. Advanced Biofuel Feedstock Incentives

The Biomass Crop Assistance Program (BCAP; Section 9010) provides financial assistance to landowners and operators that establish, produce, and deliver biomass feedstock crops for advanced biofuel production facilities. Qualified feedstock producers are eligible for a reimbursement of 75% of the cost of establishing a biomass feedstock crop, as well as annual payments for up to five years for herbaceous feedstocks and up to 15 years for woody feedstocks. The annual payment values are determined based primarily on the crop value; producers receive 99% of the value if the biomass is harvested to produce cellulosic biofuels that meet the U.S. Environmental Protection Agency’s Renewable Fuels Standard Program standards, 90% if it is harvested for other advanced biofuels, and 75% if it is harvested for heat, power, or biobased products. In addition, BCAP provides qualified biomass feedstock crop producers matching payments for the collection, harvest, storage, and transportation of their crops to advanced biofuel production facilities for up to two years. The matching payments are $1 for each $1 per dry ton paid by a qualified advanced biofuel production facility, up to $45 per dry ton. For more information, see the Biomass Crop Assistance Program website.

12. Second Generation Biofuel Plant Depreciation Deduction Allowance

A second generation biofuel production plant placed into service between December 20, 2006, and December 31, 2013, may be eligible for an additional depreciation tax deduction allowance equal to 50% of the adjusted basis of the property. The plant must be solely used to produce second generation biofuel and is only eligible for the depreciation allowance for the first year in operation. Second generation biofuel is defined as liquid fuel produced from any lignocellulosic or hemicellulosic matter that is available on a renewable basis or any cultivated algae, cyanobacteria, or lemna.

13. Second Generation Biofuel Producer Tax Credit

A second generation biofuel producer that is registered with the Internal Revenue Service (IRS) may be eligible for a tax incentive in the amount of up to $1.01 per gallon of second generation biofuel that is: sold and used by the purchaser in the purchaser’s trade or business to produce a second generation biofuel mixture; sold and used by the purchaser as a fuel in a trade or business; sold at retail for use as a motor vehicle fuel; used by the producer in a trade or business to produce a second generation biofuel mixture; or used by the producer as a fuel in a trade or business. If the second generation biofuel also qualifies for alcohol fuel tax credits, the credit amount is reduced to $0.46 per gallon for biofuel that is ethanol and $0.41 per gallon if the biofuel is not ethanol. Second generation biofuel is defined as liquid fuel produced from any lignocellulosic or hemicellulosic matter that is available on a renewable basis or any cultivated algae, cyanobacteria, or lemna. To qualify, fuel must also meet the U.S. Environmental Protection Agency fuel and fuel additive registration requirements. Alcohol with a proof of less than 150, fuel with a water or sediment content of more than 4%, and fuel with an ash content of more than 1% are not considered second generation biofuels. The incentive is allowed as a credit against the producer’s income tax liability. Under current law, only qualified fuel produced in the United States between January 1, 2009, and December 31, 2013, for use in the United States may be eligible. For more information, see IRS Publication 510 and IRS Forms 637 and 6478, which are available via the IRS website.

Point of Contact: Excise Tax Branch, U.S. Internal Revenue Service Office of Chief Counsel

1.5 Renewable Fuel Legislature in the United States

The renewable fuel agenda in the United States is implemented by federal laws and regulations. These acts give guidelines as well as directions and, most importantly, provide the legal support for federal agencies in the implementation of sustainable energy programs. The Energy Policy Act of 1992 (102nd Congress H.R.776.ENR, abbreviated as EPACT92) is one of the earliest legislatures. It was passed by Congress and addressed energy efficiency, energy conservation and energy management (Title I), natural gas imports and exports (Title II), alternative fuels and requiring certain fleets to acquire alternative fuel vehicles, which are capable of operating on non petroleum fuels (Title III-V), electric motor vehicles (Title VI), radioactive waste (Title VIII), coal power and clean coal (Title XIII), renewable energy (Title XII), and other issues. It reformed the Public Utility Holding Company Act and amended parts of the Federal Power Act of 1935 (Title VII). The Energy Policy Act (EPAct) of 1992 set goals, created mandates, and amended utility laws to increase clean energy use and improve overall energy efficiency in the United States. The Act consists of twenty-seven titles detailing various measures designed to lessen the nation’s dependence on imported energy, provide incentives for clean and renewable energy and promote energy conservation in buildings. The EPAct directed the federal government to decrease energy consumption in federal buildings when feasible and to integrate the use of alternative fuel vehicles in federal and state fleets. Title XXII in the EPAct authorized tax incentives and marketing strategies for renewable energy technologies in an effort to encourage commercial sales and production.

The next Act was the Energy Policy Act of 2005 (Pub. L 109–58). This is a bill passed by the United States Congress on July 29, 2005, and signed into law by President George W. Bush. The act, described by proponents as an attempt to combat growing energy problems, changed US energy policy by providing tax incentives and loan guarantees for energy production of various types. The Energy Policy Act of 2005 authorized loan guarantees for innovative technologies that avoid greenhouse gases as well as carbon capture and storage and renewable energy. The Act increases the amount of ethanol that must be mixed with gasoline sold in the United States to 4 billion US gallons by 2006, 6.1 billion US gallons by 2009. However, two years later, another more comprehensive Act was passed in the Congress and some of the important features in this Act and other more recent Federal Government Acts are outlined below.

1.5.1 Renewable Fuel Standards of Energy Independence and Security Act of 2007

The United States renewable fuel standards of the Energy Independence and Security Act of 2007 is used as a guideline for the future of renewable energy [25]. The stated purpose of the Act is “to move the United States toward greater energy independence and security, to increase the production of clean renewable fuels, to protect consumers, to increase the efficiency of products, buildings, and vehicles, to promote research and deploy greenhouse gas capture and storage options, and to improve the energy performance of the Federal Government, and for other purposes.” The bill originally sought to cut subsidies to the petroleum industry in order to promote petroleum independence and different forms of alternative energy. These tax changes were ultimately dropped after opposition in the Senate, and the final bill focused on automobile fuel economy, development of biofuels, and energy efficiency in public buildings and lighting. This 2007 bill outlined the US targets for advanced non-cellulosic biofuel and cellulosic biofuels. These original targets in the Renewable Fuel Standards of Energy Independence and Security Act of 2007 are shown in Table 1.3 [25].

Table 1.3 Renewable fuel standards or targets of the Energy Independence and Security Act of 2007 [25].

According to the expectations of this Act, conventional biofuels such as corn ethanol are expected to grow till 2015, and remain constant at a production level of 15.0 billion gallons per year, whereas, cellulosic biofuels are expected to grow continuously in the projected period till 2022.

1.5.2 US EPA 2013 Renewable Fuel Standards

According to the Renewable Fuel Standard (RFS) program of the Energy Independence and Security Act of 2007, the projected target for cellulosic ethanol for the year 2013 is 1.00 BG (Table 1.3). However the current US cellulosic ethanol production capacity is far below the expected target. Therefore, the target has been revised based on current advancements in technology and industry capabilities. Under the Clean Air Act Section 211 (o), as amended by the Energy Independence and Security Act of 2007, the Environmental Protection Agency (EPA) is required to set the annual standards under the RFS program for the following year based on gasoline and diesel projections from the Energy Information Administration (EIA). The EPA is also required to set the cellulosic biofuel standard each year based on the volume projected to be available during the following year, using EIA projections and assessments of production capability from industry. This U.S. EPA rulemaking provides an evaluation of the expected volumes of cellulosic biofuel at 14 million gallons. This is a more reasonable representation of the expected production. This approach to developing the cellulosic ethanol standards for 2013 is consistent with a January 2013 ruling from U.S. Court of Appeals for Washington, D.C.

Furthermore, the EPA will consider public comments before setting the annual cellulosic standards beyond 2013. This action also proposes to set the 2013 volume requirements for advanced biofuel and total renewable fuel at the levels required by the statute at 2.75 and 16.55 billion gallons, respectively. The EPA previously set the 2013 volume requirement for biomass-based diesel in a separate action, finalizing a volume of 1.28 billion gallons. All volumes are ethanol-equivalent, except for biomass-based diesel which is the actual biodiesel volume. The EPA is also using the applicable volumes that are specified in the statute to set the percentage standards for advanced biofuel and total renewable fuel for 2013. These EPA expected volumes for 2013 are shown in Table 1.4 [26].

Table 1.4 Revised standards for 2013 [26]. All volumes are ethanol-equivalent, except for biomass-based diesel, which is the actual biodiesel volume.

Cellulosic biofuel

14 MG

Biomass-based diesel

1.28 BG

Advanced biofuel

2.75 BG

Renewable fuel

16.55 BG

In addition to this, four separate percentage standards are required under the RFS program, corresponding to the four separate volume requirements shown in Table 1.4. The percentage standards represent the ratio of renewable fuel volume to nonrenewable gasoline and diesel volume. Thus, in 2013 about 10% of all fuel used will be from renewable sources. The standards for 2013 are shown in Table 1.5.

Table 1.5 Proposed percentage standards for 2013; the percentage standards represent the ratio of renewable fuel volumes to non-renewable gasoline and diesel volume [26].

Cellulosic biofuel

0.008%

Biomass-based diesel

1.12%

Advanced biofuel

1.60%

Renewable fuel

9.63%

The U.S. Environmental Protection Agency document Federal Register, Vol. 7, No. 26, published on February 7, 2013 gives a detailed breakdown of the 14 MG cellulosic biofuel projection for 2013. This estimate includes cellulosic ethanol as well as cellulose-based hydrocarbon liquid fuels [27].

References

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2. REN, Renewables 2012 global status report, 2012, Renewable Energy Policy Network for the 21st Century: Paris: REN21 Secretariat.

3. IEA, World energy outlook 2012, 2012, IEA: International Energy Agency 9 rue de la Fédération 75739 Paris Cedex 15, France.

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14. G. Najafi, B. Ghobadian, and T.F. Yusaf, Algae as a sustainable energy source for biofuel production in Iran: A case study. Renewable and Sustainable Energy Reviews, 2011. 15(8): p. 3870–3876.

15. F. Ma and M.A. Hanna, Biodiesel production: A review. Bioresource Technology, 1999. 70(1): p. 1–15.

16. J.M. Marchetti, V.U. Miguel, and A.F. Errazu, Possible methods for biodiesel production. Renewable and Sustainable Energy Reviews, 2007. 11(6): p. 1300–1311.

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18. E. Santacesaria, G.M. Vicente, M. Di Serio, and R. Tesser, Main technologies in biodiesel production: State of the art and future challenges. Catalysis Today, 2012. 195(1): p. 2–13.

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22. E.P. Monthly, US Energy Information Administration, U.D.o. Energy, Editor 2013.

23. IEA, Advanced Motor Fuels Annual Report 2010, ed. I.E. Agency 2010, NREL, Boulder: NREL.

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27. Federal Register, Vol. 78, No. 26, in 40CFR Part 80, Regulations of Fuels and Fuel Additives, P.V. Environmental Protection Agencey, Editor 2013.

Chapter 2

Bioethanol as a Transportation Fuel

2.1 Introduction — History of Bioethanol as a Transportation Fuel

Ethanol and ethanol blends have a long history as alternative transportation fuels. As far back as 1826, Samuel Morey used an ethanol turpentine mixture as the fuel in his experiments with internal combustion engines. In 1860, Nicholas Otto began experimenting with ethanol-powered internal combustion engines. In the United States, bioethanol and ethanol turpentine blends were popular as fuels long before the development of petroleum crude oil-based gasoline as a fuel. Oil was found in 1859 in Pennsylvania, and later, the discovery of a ready supply of oil in Texas and other parts of the United States coupled with unfavorable taxation on ethanol-based fuels made gasoline and kerosene more popular fuels. Early US automobile engines were developed to run on pure ethanol or ethanol blends. In 1896, Henry Ford designed his first automobile, the “Quadricyle” to run on pure ethanol [1]. The famous Ford Model T, generally regarded as the earliest affordable automobile, was first manufactured in 1908 and was capable of running on gasoline, ethanol, or a gasoline-ethanol mixture [1].