Biohydrogen Production: Fundamentals and Technology Advances

© 2008 Taylor & Francis Group, LLC

Chemical Engineering

“…covers the biological hydrogen production authoritatively from A to Z … I

strongly recommend this excellent book to energy scientists, engineers, and students

who are interested in hydrogen production in general and biological hydrogen

production in particular, as well as to industrial concerns that are looking for

inexpensive hydrogen production technologies.”

—T. Nejat Veziroğlu, President, International Association for Hydrogen Energy

“... an excellent contemporary review of the biohydrogen production research field.”

—Nils-Kåre Birkeland, University of Bergen, Norway

Biohydrogen Production: Fundamentals and Technology Advances covers

the fundamentals of biohydrogen production technology, including microbiology,

biochemistry, feedstock requirements, and molecular biology of the biological

hydrogen production processes. It also gives insight into scale-up problems and

limitations. In addition, the book discusses mathematical modeling of the various

processes involved in biohydrogen production and the software required to model

the processes. The book summarizes research advances that have been made in

this field and discusses bottlenecks of the various processes, which presently limit

the commercialization of this technology.

The authors also focus on the process economy, policy, and environmental impact

of this technology, since the future of biohydrogen production depends not only on

research advances, but also on economic considerations (the cost of fossil fuels),

social espousal, and the development of H2

energy systems. The book describes the

fundamentals of this technology interwoven with more advanced research findings.

Further reading is suggested at the end of each chapter.

Since the beauty of any innovation is its applicability, socioeconomic impact, and

cost energy analysis, the book examines each of these points to give you a holistic

picture of this technology. Illustrative diagrams, flow charts, and comprehensive

tables detailing the scientific advancements provide an opportunity to understand

the process comprehensively and meticulously. Written in a lucid style, the book

supplies a complete knowledge bank about biohydrogen production processes.

ISBN: 978-1-4665-1799-8

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Biohydrogen Production

Fundamentals and Technology Advances

Das

Dasgupta

Khanna

Biohydrogen Production

Debabrata Das

Namita Khanna

Chitralekha Nag Dasgupta

www.crcpress.com

K15140

K15140 mech FINAL.indd 1 1/21/14 10:13 AM

© 2008 Taylor & Francis Group, LLC

Biohydrogen Production

Fundamentals and Technology Advances

© 2008 Taylor & Francis Group, LLC

Biohydrogen Production

Fundamentals and Technology Advances

Debabrata Das

Namita Khanna

Chitralekha Nag Dasgupta

CRC Press

Taylor & Francis Group

6000 Broken Sound Parkway NW, Suite 300

Boca Raton, FL 33487-2742

© 2014 by Taylor & Francis Group, LLC

CRC Press is an imprint of Taylor & Francis Group, an Informa business

No claim to original U.S. Government works

Version Date: 20131021

International Standard Book Number-13: 978-1-4665-1800-1 (eBook - PDF)

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© 2008 Taylor & Francis Group, LLC v

Contents

Foreword ................................................................................................................xv

Preface.................................................................................................................. xvii

Authors ................................................................................................................. xix

1. Introduction.....................................................................................................1

1.1 Introduction ...........................................................................................1

1.1.1 Global Environmental Issues .................................................1

1.2 Nonconventional Energy Resources ..................................................2

1.2.1 Solar Energy .............................................................................4

1.2.2 Wind Energy.............................................................................7

1.2.3 Hydropower..............................................................................8

1.2.4 Tidal Energy .............................................................................9

1.2.5 Geothermal Energy .................................................................9

1.2.6 Biomass Energy........................................................................9

1.2.7 Hydrogen Energy and Fuel Cell.......................................... 11

1.3 Conventional Hydrogen Technologies and Limitations ...............12

1.4 Biological Hydrogen Production Technology................................. 15

1.5 Properties of Hydrogen...................................................................... 19

1.5.1 Fuel Properties of Hydrogen................................................ 19

1.6 Book Overview....................................................................................20

References ....................................................................................................... 21

2. Microbiology .................................................................................................23

2.1 Introduction .........................................................................................23

2.2 Dark Fermentative Bacteria ...............................................................25

2.2.1 Adaptation to Temperature ..................................................25

2.2.1.1 Thermophiles..........................................................30

2.2.1.2 Mesophiles ..............................................................30

2.2.1.3 Psychrophiles.......................................................... 31

2.2.2 Tolerance to Oxygen.............................................................. 31

2.2.2.1 Obligate Anaerobes................................................ 31

2.2.2.2 Facultative Anaerobes ...........................................33

2.2.2.3 Aerobes ....................................................................35

2.2.3 Fermentative End Products ..................................................35

2.2.3.1 Lactic Acid Fermentation......................................36

2.2.3.2 Mixed Acid Fermentation .....................................36

2.2.3.3 Butyric Acid Fermentation....................................36

2.2.3.4 Butanol−Acetone Fermentation............................36

2.3 Photosynthetic Fermentative Bacteria .............................................36

2.3.1 Purple Bacteria ....................................................................... 37

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2.3.1.1 Sulfur Bacteria ........................................................ 37

2.3.1.2 Nonsulfur Bacteria.................................................38

2.3.2 Green Bacteria ........................................................................39

2.3.2.1 Sulfur Bacteria ........................................................39

2.3.2.2 Gliding Bacteria......................................................39

2.4 Cyanobacteria ......................................................................................40

2.4.1 Anabaena ................................................................................ 41

2.4.2 Nostoc...................................................................................... 41

2.4.3 Synechocystis ......................................................................... 41

2.5 Green Algae .........................................................................................42

2.5.1 Chlamydomonas ....................................................................42

2.6 Concept of Consortia Development .................................................43

2.7 Synthetic Microorganisms—Are They the Future? .......................44

Glossary...........................................................................................................45

References .......................................................................................................45

3. Hydrogen Production Processes................................................................55

3.1 Introduction .........................................................................................55

3.2 Photobiological Hydrogen Production ............................................57

3.2.1 Basic Principles of Photobiological Hydrogen

Production...............................................................................57

3.2.1.1 Photoautotrophic Production of Hydrogen........57

3.2.1.2 Photoheterotrophic Production of Hydrogen......58

3.2.2 Fundamentals of Photosynthesis and Biophotolysis

of Water ...................................................................................58

3.2.3 Biophotolysis...........................................................................60

3.2.3.1 Direct Biophotolysis...............................................60

3.2.3.2 Indirect Biophotolysis............................................65

3.2.4 General Considerations and Advancements Made

in Biophotolysis ......................................................................68

3.2.4.1 Explosive Hydrogen–Oxygen Mixture ...............68

3.2.4.2 Oxygen Sensitivity of the Enzymes

Involved in Hydrogen Production.......................68

3.2.4.3 Inefficiency of Biophotolysis Process Due

to Large Antennae Size .........................................69

3.2.4.4 Quantum Efficiency............................................... 70

3.2.4.5 Availability of More Reductant............................ 70

3.2.4.6 Natural Coupling of Photosynthetic

Electron Transport to Proton Gradient ...............71

3.2.4.7 Photobioreactors.....................................................71

3.3 Photofermentation ..............................................................................72

3.3.1 General Considerations and Advancements Made

in Photofermentation.............................................................77

3.3.1.1 Immobilization Approaches.................................77

3.3.1.2 Scale-Up Considerations .......................................79

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3.4 Dark Fermentation.............................................................................. 81

3.4.1 Anaerobic Fermentation ....................................................... 81

3.4.2 General Considerations to Commercialization

of the Technology...................................................................84

3.4.2.1 Low Yield and Rate of Production.......................85

3.4.2.2 Processing of Some Biomass Feed Stock

Is Too Costly............................................................85

3.4.2.3 Incomplete Substrate Degradation ......................85

3.4.2.4 Lack of Robust Industrial Strain..........................86

3.4.2.5 Engineering Issues .................................................86

3.4.2.6 Sensitivity of Hydrogenase to Oxygen ...............86

3.4.2.7 Mixed Consortia Have Methanogens:

Suppression of Methanogen Activity..................88

3.4.2.8 Low Gaseous Energy Recovery............................88

3.4.2.9 Biomass and End Metabolite Formation

Compete with Hydrogen Production..................89

3.4.2.10 Thermodynamic Limitations................................89

3.4.2.11 Integration of Processes.........................................89

3.4.3 Progress Made in the Field of Dark Fermentation............90

3.4.3.1 Overcoming Techno-Engineering Barriers ........90

3.4.3.2 Molecular Advancements .....................................90

3.4.3.3 Modeling and Optimization of the Process .......90

3.4.3.4 Pilot Scale Demonstration of the Technology...... 91

3.5 Hybrid Processes.................................................................................92

3.5.1 Integration of Dark Fermentative Process with

Photofermentation .................................................................92

3.5.1.1 Lactic Acid Fermentation Integrated

with Photofermentation ........................................93

3.5.1.2 Acetic Acid Fermentation Integrated with

Photofermentation..................................................94

3.5.1.3 Mixed Acid Fermentation .....................................94

3.5.2 Integration of Biophotolysis with Dark Fermentative

Process and Photofermentation...........................................95

3.5.3 Integration of Biophotolysis with Photofermentation......95

3.5.4 Biohydrogen Production Integrated with Anaerobic

Methane Production..............................................................96

3.6 Microbial Electrolysis Cell.................................................................97

3.7 Thermodynamic Limitations ............................................................98

Glossary......................................................................................................... 100

References ..................................................................................................... 100

4. Biohydrogen Feedstock ............................................................................. 111

4.1 Introduction ....................................................................................... 111

4.2 Simple Sugars as Feedstock............................................................. 111

4.3 Complex Substrates as Feedstock...................................................123

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4.4 Biomass Feedstock............................................................................123

4.5 Organic Acids .................................................................................... 124

4.6 Waste as Feedstock ...........................................................................125

4.7 Assessment of Cost Components for Several Feedstocks

for Dark Hydrogen Fermentation...................................................125

4.8 Conclusion.......................................................................................... 126

Glossary......................................................................................................... 126

References ..................................................................................................... 126

5. Molecular Biology of Hydrogenases and Their Accessory Genes....... 133

5.1 Introduction ....................................................................................... 133

5.2 Occurrence of Hydrogenase in Nature.......................................... 134

5.3 Classification of Hydrogenases....................................................... 138

5.3.1 [Fe-only] Hydrogenases ...................................................... 138

5.3.2 [NiFe] Hydrogenase: Structure and Location.................. 140

5.3.2.1 Group 1: [NiFe] Uptake Hydrogenase............... 141

5.3.2.2 Group 2: Cyanobacterial Uptake

Hydrogenases and Hydrogen Sensors.............. 142

5.3.2.3 Group 3: Multimeric Soluble

Hydrogenases ....................................................... 142

5.3.2.4 Group 4: Escherichia coli Hydrogenase 3............ 143

5.3.2.5 Structural Organization of the Genes￾Encoding [NiFe] Hydrogenases and Their

Physiological Role in the Organism .................. 143

5.3.2.6 Biosynthesis of [NiFe] Hydrogenases................ 147

5.3.2.7 Transcriptional Regulation of [NiFe]

Hydrogenases ....................................................... 151

5.3.3 [FeFe]-Hydrogenase: Structure and Location.................. 154

5.3.3.1 [FeFe]-Hydrogenase Active Site ......................... 156

5.3.3.2 [FeFe]-Hydrogenase Maturation Machinery.... 157

5.4 Problems Associated with Oxygen Sensitivity of

Hydrogenases and Plausible Solutions.......................................... 160

5.4.1 Reasons for Oxygen Insensitivity of Hydrogenase ........ 162

5.4.1.1 Blocking of the Active Site by Partial

or Complete Reduction Product of

Attacking Oxygen ................................................ 162

5.4.1.2 Protective Role of FeS Clusters

Surrounding the Active Site ............................... 163

5.4.1.3 Role of Conformation of Gas Channels in

Delivering Oxygen Tolerance ............................. 163

5.4.2 Possible Solutions to Overcome Oxygen Insensitivity

of Hydrogenase .................................................................... 164

5.4.2.1 Change in the Amino Acid Residues of

the Gas Channels ................................................. 164

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© 2008 Taylor & Francis Group, LLC

5.4.2.2 Overexpression of Oxygen-Tolerant

Hydrogenases ....................................................... 164

5.4.2.3 Nano-Technology to the Rescue: Creating

Anoxic Environments within the Organism

to Enhance Hydrogen Production ..................... 165

5.4.2.4 Gene Shuffling for Rapid Generation

of Hydrogen .......................................................... 165

5.5 Evolutionary Significance of Hydrogenase................................... 167

5.5.1 Role of Hydrogenase during Nitrogen Fixation.............. 167

5.5.2 Role of Hydrogenase during Methanogenesis ................ 168

5.5.3 Role of Hydrogenase in Bioremediation........................... 169

5.6 Conclusion.......................................................................................... 169

Glossary......................................................................................................... 169

References ..................................................................................................... 170

6. Improvement of Hydrogen Production through Molecular

Approaches and Metabolic Engineering ............................................... 179

6.1 Introduction ....................................................................................... 179

6.2 Molecular Approaches ..................................................................... 179

6.2.1 Improvement of Biomass Production ............................... 179

6.2.1.1 CO2-Concentrating Mechanisms (CCMs)......... 188

6.2.1.2 Cell Cycle............................................................... 189

6.2.2 Enhancing the Uptake of External Substrate................... 190

6.2.3 Improvement of Photoconversion Efficiency................... 190

6.2.4 Improvement of Hydrogen-Producing Enzymes............ 193

6.2.4.1 Improvement of Hydrogenase............................ 193

6.2.4.2 Improvement of Nitrogenase.............................. 194

6.2.4.3 Overexpression of Enzymes ............................... 196

6.2.5 Introduction of Foreign Hydrogenase .............................. 196

6.2.6 Deletion of Hydrogen Uptake Genes................................200

6.2.7 Other Approaches................................................................ 202

6.2.7.1 Generation of Anaerobic Condition .................. 202

6.2.7.2 ATP Synthase Modification for Enhanced

Hydrogen Production.......................................... 202

6.2.7.3 Linking of Hydrogenase to Cyanobacterial

Photosystems ........................................................203

6.2.7.4 Engineering of Heterocyst Frequency ..............204

6.3 Metabolic Engineering .....................................................................205

6.3.1 Proteomic Analysis..............................................................205

6.3.2 Redirecting the Electron Pull toward Hydrogen

Production.............................................................................206

6.4 Conclusion..........................................................................................209

Glossary......................................................................................................... 210

References ..................................................................................................... 211

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© 2008 Taylor & Francis Group, LLC

7. Process and Culture Parameters.............................................................. 219

7.1 Introduction ....................................................................................... 219

7.2 Factors Affecting Dark Fermentation Process .............................. 219

7.2.1 Effect of Inoculum on Fermentative Hydrogen

Production.............................................................................220

7.2.2 Temperature.......................................................................... 231

7.2.3 Effect of pH on Biohydrogen Production.........................234

7.2.4 Effect of Alkalinity on Biohydrogen Production ............ 237

7.2.5 Effect of Hydraulic Retention Time on Biohydrogen

Production.............................................................................238

7.2.6 Hydrogen and CO2 Partial Pressure ................................. 240

7.2.7 Effect of Metal Ion on Fermentative Hydrogen

Production............................................................................. 243

7.2.7.1 Effect of Iron and Nickel on Fermentative

Hydrogen Production.......................................... 243

7.2.7.2 Effect of Magnesium on Fermentative

Biohydrogen Production ..................................... 245

7.2.7.3 Effect of Other Heavy Metals on

Fermentative Biohydrogen Production............. 246

7.2.7.4 Effect of Nitrogen and Phosphate on

Fermentative Biohydrogen Production............. 247

7.3 Environmental Factors Affecting Hydrogen Production

in Photosynthetic Organisms.......................................................... 248

7.3.1 Effect of Light Intensity....................................................... 248

7.3.2 Effect of Temperature..........................................................250

7.3.3 Effect of Nitrogen.................................................................250

7.3.4 Effect of Sulfur .....................................................................250

7.4 Statistical Optimization of Factors Effecting Biohydrogen

Production.......................................................................................... 251

7.5 Comparison of Suspended Cell versus Immobilized Systems...... 252

7.6 Comparison of Batch Process versus Continuous Process .........254

7.7 Conclusion..........................................................................................254

Glossary.........................................................................................................256

References .....................................................................................................256

8. Photobioreactors ......................................................................................... 267

8.1 Introduction ....................................................................................... 267

8.2 Types of PBRs .................................................................................... 267

8.2.1 Closed System PBRs ............................................................268

8.2.1.1 Tubular Reactors...................................................268

8.2.1.2 Flat Panel PBRs .....................................................272

8.2.2 Other Reactors Geometries ................................................ 274

8.2.2.1 Torus-Shaped Reactor.......................................... 274

8.2.2.2 Annular Triple-Jacketed Reactor........................ 274

8.2.2.3 Induced–Diffused PBR........................................277

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8.3 Physicochemical Parameters ........................................................... 278

8.3.1 Physical Parameters Affecting Performance

of a PBR.................................................................................. 278

8.3.2 Physicochemical Parameters Affecting the

Performance of a PBR.......................................................... 278

8.3.3 Other Factors Affecting Hydrogen Production and

Biomass Production.............................................................280

8.4 Design Criteria ..................................................................................280

8.4.1 Features of an Efficient PBR ...............................................280

8.4.2 Light-Related Design Considerations ...............................280

8.4.3 Temperature as a Design Criterion ................................... 281

8.4.4 Sterility (Species Control) and Cleanability..................... 282

8.4.5 Surface Area to Volume (A/V) Ratio ................................ 282

8.4.6 Oxygen Removal..................................................................283

8.4.7 Mixing ...................................................................................283

8.4.8 Material of Construction.....................................................284

8.5 Comparison of the Performance of the PBRs................................286

8.6 Energy Analysis ................................................................................ 287

8.7 Conclusion..........................................................................................288

Glossary.........................................................................................................288

References .....................................................................................................289

9. Mathematical Modeling and Simulation of the Biohydrogen

Production Processes ................................................................................. 295

9.1 Introduction ....................................................................................... 295

9.2 Development of Mathematical Models to Correlate

Substrate and Biomass Concentration with Time ........................ 296

9.2.1 Monod’s Model for Cell Growth Kinetics ........................ 296

9.2.2 Determination of Cell Mass Concentration and

Substrate Concentration...................................................... 297

9.2.3 Modeling and Simulation of the Fermentation

Process ................................................................................... 298

9.2.4 Regression Analysis of Simulated Values Obtained

from Monod’s Model and Experimentally

Obtained Values...................................................................299

9.2.4.1 Coefficient of Determination (R2

).......................299

9.2.5 Other Monod’s Type Models.............................................. 301

9.2.5.1 Monod-Type Model Including pH

Inhibition Term..................................................... 301

9.3 Substrate Inhibition Model..............................................................302

9.3.1 Modified Andrew’s Model .................................................302

9.3.1.1 Simulation of Cell Mass Concentration

and Substrate Concentration Profiles ................302

9.3.2 Simulation of the Biohydrogen Production Process

with Substrate Inhibition....................................................303

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© 2008 Taylor & Francis Group, LLC

9.3.3 Regression Analysis of Simulated Values Obtained

from Substrate Inhibition Model and Experimentally

Obtained Values...................................................................304

9.4 Determination of Cell Growth Kinetic Parameters:

KS, μmax, Ki ...........................................................................................305

9.4.1 Kinetic Parameters and Their Estimation........................305

9.4.2 Calculation of Kinetic Parameters Using the Method

of Least Squares ...................................................................306

9.5 Cumulative Hydrogen Production by Modified Gompertz’s

Equation..............................................................................................307

9.5.1 Modified Gompertz’s Equation .........................................308

9.5.2 Modified Gompertz’s Equation for Modeling

Hydrogen, Butyrate, and Acetate Production..................308

9.5.3 Product Formation Kinetics by the Luedeking–Piret

Model..................................................................................... 310

9.6 Development of Mathematical Models for Cell Growth

Kinetics in Photofermentation Process.......................................... 312

9.6.1 Logistic Equation ................................................................. 312

9.6.2 Modified Logistic Model .................................................... 312

9.7 Modeling of Hydrogen Production by Photofermentation......... 313

9.7.1 Modified Gompertz’s Equation ......................................... 313

9.7.2 Overall Biohydrogen Production Rate and

Hydrogen Yield.................................................................... 313

9.7.3 Monod-Type Kinetic Model................................................ 314

9.7.4 Modification of Andrew’s Model....................................... 314

9.7.5 Generalized Monod-Type Model....................................... 314

9.8 Conclusion.......................................................................................... 315

Nomenclature............................................................................................... 315

References ..................................................................................................... 316

10. Scale-Up and Energy Analysis of Biohydrogen Production

Processes....................................................................................................... 319

10.1 Introduction ....................................................................................... 319

10.2 Determination of Scale-Up Parameters ......................................... 320

10.2.1 Geometric Similarity in Scale-Up...................................... 320

10.2.2 Scale-Up Based on Volumetric Power Consumption ..... 321

10.2.3 Volumetric Power Consumption in Agitated System.....322

10.2.4 Constant Impeller Tip Speed ............................................. 323

10.2.5 Reynolds Number................................................................ 324

10.2.6 Constant Mixing Time ........................................................ 324

10.2.7 Superficial Gas Velocity and Volumetric Gas Flow

per Unit of Liquid ................................................................ 325

10.3 Scale-Up Methods ............................................................................. 325

10.3.1 Significance of Scale-Up...................................................... 325

10.3.2 Laboratory Scale Study ....................................................... 326

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10.3.2.1 Batch Fermentation .............................................. 326

10.3.2.2 Continuous Fermentation ................................... 326

10.3.3 Scale-Up Study ..................................................................... 327

10.3.3.1 Experimental Setup for Continuous

Hydrogen Production.......................................... 327

10.4 Case Studies on Pilot-Scale Plants .................................................. 329

10.4.1 Case I: Pilot-Scale Plant Using Mixed Microflora

at Feng Chia University, Taiwan........................................ 329

10.4.1.1 Microbial Community......................................... 329

10.4.1.2 Operation Strategy and Hydrogen

Production in the Fermentor .............................. 329

10.4.2 Case II: Pilot-Scale Plant Using Distillery Effluent

to Produce Biohydrogen......................................................330

10.4.2.1 Microbial Community......................................... 331

10.4.3 Case III: Biohydrogen Production from Molasses

by Anaerobic Fermentation with a Pilot-Scale

Bioreactor System................................................................. 331

10.4.3.1 Microbial Community......................................... 332

10.4.4 Comparative Study among Different Pilot-Scale

Plants .....................................................................................333

10.5 Mass and Energy Analysis ..............................................................333

10.5.1 Material Balance of the Biohydrogen Production

Process ...................................................................................334

10.5.2 Energy Analysis of Biohydrogen Production

Process ...................................................................................334

10.5.3 Biological Route versus Chemical Route..........................335

10.5.4 Electrolysis of Water versus Biological Route for

Hydrogen Production..........................................................336

10.6 Cost Analysis of the Process............................................................336

10.6.1 Hydrogen as a Commercial Fuel .......................................336

10.6.2 Cost Calculation of Continuous Biohydrogen

Production Process Using Cane Molasses ....................... 337

10.6.2.1 Cost Analysis ........................................................ 337

10.7 Conclusion..........................................................................................339

Nomenclature...............................................................................................340

Glossary.........................................................................................................341

References .....................................................................................................341

11. Biohydrogen Production Process Economics, Policy,

and Environmental Impact.......................................................................343

11.1 Introduction .......................................................................................343

11.2 Process Economy...............................................................................343

11.2.1 Technical and Cost Challenges..........................................345

11.2.1.1 Production.............................................................346

11.2.1.2 Storage....................................................................346

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11.2.1.3 Distribution Cost..................................................348

11.2.1.4 Supply Cost and Demand...................................348

11.2.1.5 Conversion.............................................................349

11.2.2 Economics of a Hydrogen Infrastructure......................... 351

11.3 Environmental Impact .....................................................................356

11.4 Hydrogen Policy................................................................................358

11.5 Issues and Barriers............................................................................364

11.6 Status of Hydrogen in the Developed and the

Developing Countries.......................................................................364

11.6.1 United States.........................................................................365

11.6.2 Europe ...................................................................................366

11.6.3 Asia–Pacific........................................................................... 367

11.7 Future Outlook.................................................................................. 367

Glossary.........................................................................................................368

References .....................................................................................................368