Environmental impacts of renewable energy f spellman (CRC, 2015)

In contrast to fossil fuels, renewable energy—wind, solar, geothermal, hydroelectric, biomass for electricity, and hydrokinetic—provide sub-stantial benefits for our climate, our health,

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ENVIRONMENTAL IMPACTS OF

RENEWABLE

ENERGY

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ENERGY AND THE ENVIRONMENT

Energy Resources: Availability, Management, and Environmental Impacts

Kenneth J Skipka and Louis Theodore

Finance Policy for Renewable Energy and a Sustainable Environment

Solar and Infrared Radiation Measurements

Frank Vignola, Joseph Michalsky, and Thomas Stoffel

Forest-Based Biomass Energy: Concepts and Applications

Frank Spellman

Introduction to Renewable Energy

Vaughn Nelson

Solar Energy: Renewable Energy and the Environment

Robert Foster, Majid Ghassemi, Alma Cota, Jeanette Moore, and Vaughn Nelson

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ENVIRONMENTAL IMPACTS OF

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As humans we tend to forget that Mother Nature does not need us

to flourish and survive; instead, we need Earth to survive, period.

To a person with a saw, everything looks like lumber.

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Contents

Preface xv

To the Reader xvii

Author xix

Chapter 1 Setting the Stage: The 411 on Energy Basics 1

Energy 1

Types of Energy 2

Nonrenewable Energy 3

Benefits 3

Non-Benefits 3

Renewable Energy 4

Benefits 4

Non-Benefits 4

Energy Use in the United States 4

Measuring Energy 5

Heat Engines 6

Rankine Cycle Heat Engine 7

Stirling Cycle Heat Engine 8

Thought-Provoking Questions 8

References and Recommended Reading 8

Chapter 2 Wind Power: Where Eagles Don’t Dare 11

Introduction 11

Wind Power Basics 13

Air in Motion 13

Wind Energy 14

Wind Power 16

Wind Turbine Types 16

Horizontal-Axis Wind Turbines 16

Wind Turbine Components 18

Wind Energy Site Evaluation Impacts 19

Air Quality 19

Cultural Resources 20

Ecological Resources 20

Water Resources 20

Land Use 20

Soils and Geologic Resources 20

Paleontological Resources 21

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Transportation 21

Visual Resources 21

Socioeconomics 21

Environmental Justice 21

Hazardous Materials and Waste Management 21

Acoustics (Noise) 21

Wind Energy Construction Impacts 34

Air Quality 34

Water Resources 36

Land Use 36

Transportation 38

Visual Resources 38

Socioeconomics 42

Wind Energy Operations Impacts 43

Air Quality 43

Water Resources 44

Land Use 44

Transportation 45

Visual Resources 45

Socioeconomics 46

Wind Energy Impacts on Wildlife 46

Motion Smear 50

Law of the Visual Angle 51

Wind Energy Impacts on Human Health 53

Power Transmission Lines 55

Energy Transmission Site Evaluation Impacts 55

Air Quality 55

Water Resources 56

Land Use 56

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Contents

Transportation 57

Visual Resources 57

Socioeconomics 57

Energy Transmission Construction Impacts 57

Air Quality 57

Water Resources 58

Land Use 59

Transportation 60

Visual Resources 60

Socioeconomics 61

Energy Transmission Operations Impacts 61

Air Quality 61

Water Resources 62

Land Use 62

Transportation 63

Visual Resources 63

Socioeconomics 64

Wind Turbine Operations and Maintenance Personnel Safety Concerns 64

Wind Energy Fatalities/Incidents 64

Case Study 2.1 Wind Turbine Fatality 65

Wind Turbine Hazards and Applicable OHSA Standards and Controls 66

Wind Power: The Bottom Line 72

Chapter 3 Solar Energy 77

Icarus Revisited at Ivanpah 77

Energy from the Sun 77

Photovoltaics 78

Concentrating Solar Power 80

Environmental Impacts of Solar Energy 81

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Land Use and Siting 81

Water Resources 82

Hazardous Waste 87

Ecological Impacts 89

Solar Energy Job Hazards 91

Fatalities and Incidents 91

Hazards and Controls 92

Chapter 4 Hydropower 103

The Rachel River 103

Historical Perspective 108

Impoundment 111

Diversion 111

Pumped Storage 111

Key Definitions 111

Hydropower Basic Concepts 112

Stevin’s Law 113

Properties of Water 114

Reservoir Stored Energy 126

Hydroturbines 128

Advanced Hydropower Technology 131

Hydropower Generation: Dissolved Oxygen Concerns 132

Ecological Impacts of Hydropower 133

Physical Barrier to Fish Migration 133

Flow Alterations, Flow Fluctuations, and Regulated and Unregulated Rivers and Salmonids 134

Biological Impacts of Flow Fluctuations 137

Increases in Flow 137

Stranding 138

Juvenile Emigration (Salmonid Drift) 143

Increased Predation 143

Aquatic Invertebrates 143

Redd Dewatering 145

Spawning Interference 145

Hydraulic Response to Flow Fluctuations 146

Types of Hydropower Activity That Cause Flows to Fluctuate 146

Low Water Levels and Evaporation of Reservoirs 147

Estimating Evaporation from Lake Mead 149

Impacts on Human Health and Safety 155

Hydropower: The Bottom Line 155

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Contents

Chapter 5 Biomass/Bioenergy 163

Introduction 163

Biomass 167

Feedstock Types 167

Composition of Biomass 169

Plant Basics 171

Plant Terminology 172

Plant Cell 173

Vascular Plants 174

Leaves 175

Roots 176

Growth in Vascular Plants 177

Plant Hormones 177

Tropisms 178

Photoperiodism 178

Plant Reproduction 179

Plant Cell Walls 179

Feedstocks 180

First-Generation Feedstocks 180

Second-Generation Feedstocks: Short-Term Availability 181

Second-Generation Feedstocks: Long-Term Availability 186

Biothanol Production by Dry Corn Mill Process 189

Gasoline Gallon Equivalent (GGE) 190

Pros and Cons of Bioethanol 191

Corn for Ethanol Production or Food Supply? 192

Biomass for Biopower 195

Biomass for Bioproducts 198

Classes of Bioproducts 198

Biodiesel 200

Algae to Biodiesel 202

Algal Biomass 210

Jatropha to Biodiesel 212

Pros and Cons of Biodiesel 212

Biogas (Methane) 213

Anaerobic Digestion 213

Landfill Biogas 221

Impacts of Biomass Construction, Production, and Operation 221

Biomass Energy Construction Impacts 222

Biomass Feedstock Production Impacts 229

Biomass Energy Operations Impacts 232

Biofuel Hazards 237

Ethanol 239

Biodiesel 240

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Biofuels: The Bottom Line 240

Chapter 6 Geothermal Energy 247

Introduction 247

Geothermal Timeline 249

Geothermal Energy as a Renewable Energy Source 252

Geothermal Energy: The Basics 253

Earth’s Layers 253

Crustal Plates 254

Energy Conversion 256

Geothermal Power Plant Technologies 256

Dry Steam Power Plants 257

Flash Steam Power Plants 258

Binary Cycle Power Plants 258

Enhanced Geothermal Systems 259

Geothermal Heat Pumps 260

Types of Geothermal Heat Pumps 262

Environmental Impacts of Geothermal Power Development 263

Geothermal Energy Exploration and Drilling Impacts 265

Geothermal Energy Construction Impacts 268

Geothermal Energy Operations and Maintenance Impacts 272

Hazards and Controls 276

Geothermal Energy: The Bottom Line 284

Chapter 7 Marine and Hydrokinetic Energy 287

Introduction 287

Oceans and Their Margins 288

Ocean Floor 289

Ocean Tides, Currents, and Waves 290

Tides 290

Currents 290

Waves 291

Coastal Erosion, Transportation, and Deposition 291

Wave Erosion 291

Marine Transportation 292

Marine Deposition 292

Wave Energy 292

Wave Energy: Facts, Parameters, and Equations 293

Wave Energy Conversion Technology 295

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Contents

Tidal Energy 298

Tidal Energy Technologies 300

Ocean Thermal Energy Conversion 301

Ocean Energy Conversion Process 301

Types of OTEC Technologies 303

Ocean Energy and Hydrokinetic Technology Impacts 303

Alteration of River or Ocean Currents or Waves 304

Alteration of Substrates and Sediment Transport and Deposition 307

Impacts of Habitat Alterations on Benthic Organisms 308

Impacts of Noise 310

Impacts of Electromagnetic Fields 319

Toxic Effects of Chemicals 327

Interference with Animal Movements 328

Interference with Migratory Animals 331

Collisions and Strikes 332

Impacts of Ocean Thermal Energy Conversion 334

Environmental Impacts of Hydrokinetic Energy 336

Hydrokinetic Energy Site Evaluation Impacts 337

Hydrokinetic Energy Facility Construction Impacts 339

Hydrokinetic Energy Facility Operations and Maintenance Impacts 345

Marine and Hydrokinetic Energy: The Bottom Line 350

Chapter 8 Fuel Cells 361

Introduction to Hydrogen Fuel Cells 361

Hydrogen Storage 363

How a Hydrogen Fuel Cell Works 363

Environmental Impacts of Fuel Cells 364

Properties of Hydrogen 365

Thought-Provoking Question 365

Chapter 9 Carbon Capture and Sequestration 367

Introduction to Carbon Capture and Sequestration 367

Terrestrial Carbon Sequestration 369

Geologic Carbon Sequestration 373

Potential Impacts of Terrestrial Sequestration 374

Potential Impacts of Geologic Sequestration 375

Geologic Sequestration Exploration Impacts 375

Geologic Sequestration Drilling/Construction Impacts 378

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Geologic Sequestration Operations Impacts 383

Glossary 391

Appendix 1 Conversion Factors 441

Index 445

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Preface

It is generally known and widely accepted that the use of all energy sources has some impact on our environment Fossil fuels—oil, coal, and natural gas—do sub-stantially more harm than renewable energy sources by almost any measure: air and water pollution, public health, wildlife and their habitat, water use, land use, and global climate change In contrast to fossil fuels, renewable energy—wind, solar, geothermal, hydroelectric, biomass for electricity, and hydrokinetic—provide sub-stantial benefits for our climate, our health, and our economy:

• Little or no global warming emissions

• Improved public health and environmental quality

• A vast and inexhaustible energy supply

• Creation of jobs and other economic benefits

• Stable energy prices

• A more reliable and resilient energy system

However, it is important to understand that renewable energy sources also have environmental impacts The exact type and intensity of environmental impacts vary depending on the specific technology used, the geographic location, and a number

• Safety and health

Since 9/11, the intentional destruction of renewable energy sources (e.g., wind farms, solar farms, hydrokinetic systems, hydrodams, biomass feedstock and pro-duction sites, geothermal facilities, fuel cell manufacturing sites) and the accom-panying damage to the environment as a result of terrorist activities is a very real possibility All energy sources are considered critical infrastructure (and thus likely terrorist targets) by the U.S Department of Homeland Security For this reason, potential terrorist acts against renewable energy sources are addressed in this text, because the effects of such actions impact the environment in which we live

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Although carbon capture and sequestration (CCS) (or carbon capture and storage)

is not a renewable energy source, it is also discussed in this book The process of capturing waste carbon dioxide from large point sources such as fossil fuel power plants, transporting it to a storage site, and depositing it where it will not enter the atmosphere has been gaining the attention of regulators, environmentalists, and oth-ers Many view carbon capture and sequestration as a panacea in preventing global climate change In this book, we do not argue for or against the benefits of this point

of view Instead, beneficial or not, the point is made that the carbon capture and sequestration process has environmental impacts, and these are described in detail within this text The important point woven into the warp and woof of this text

is that, by understanding the current and potential environmental issues associated with each renewable energy source, we can take steps to effectively avoid, mitigate,

or minimize these impacts as renewable energy sources become a larger portion of our electric power supply

Environmental Impacts of Renewable Energy is designed to reach a wide range

of diverse student and general reader backgrounds The text focuses on the various forms of renewable energy derived from natural processes that replenish constantly: sun, wind, water (tides and waves), geothermal, biomass, hydroelectricity, biofuels, and hydrogen fuel cells Along with exploring the derivation and production of the energy we need for future use—to literally sustain our future—the book also points out that it is critical to our very survival to avoid or to limit renewable-energy-gen-erated pollution of the atmosphere, of surface water and groundwater, and of soil (the three environmental media) Because the environmental impacts of renewable energy can produce real-world problems, it logically follows that we can solve these problems by understanding the consequences of construction, operation, and main-tenance of renewable energy facilities using real-world methods; that’s what this book is all about

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To the Reader

In 1976, energy policy analyst Amory B Lovins coined the term soft energy path

to describe an alternative future where energy efficiency and appropriate able energy sources steadily replace a centralized energy system based on fossil and

renew-nuclear fuels In 2009, Joshua Green, a writer for Businessweek, pointed out that in

various publications Lovins further argued that the United States had arrived at an important crossroads and could take one of two paths The first, supported by U.S policy, promised a future of steadily increasing reliance on dirty fossil fuels and nuclear fission and had serious environmental risks The alternative, which Lovins called the “soft path,” favored “benign” sources of renewable energy such as wind power, solar power, biofuels, geothermal energy, and wave and tidal power, along with a heightened commitment to energy conservation and energy efficiency

As a lifelong student, researcher, lecturer, and ardent advocate of the development and use of renewable or alternate energy sources (eventually excluding all fossil fuel use to the extent possible), I agree with Lovins in many respects, but I take issue with those who state that renewable energy sources are “benign.” In my view, the defini-tion of the term benign means something that is harmless, innocent, innocuous, or inoffensive Thus, the labeling of renewable energy sources as benign implies that the use of renewable energy sources is totally safe The truth is the use of renewable energy sources is not totally safe

Again, I am an advocate for the use of renewable energy Simply, I think using renewable energy sources instead of fossil fuels is a good thing However, with any good thing there usually comes a bad thing Nothing made by and used by humans

is absolutely harmless to the environment … nothing … absolutely nothing Only Mother Nature, with her ultimate plan, affects nature as we know it in beneficial ways Even when she kills millions of us with her designed orchestrations (Earth- and life-altering events) that require changes to life as we know it, we must real-ize that these are simply planned and timed mechanizations Remember, Mother Nature’s plan is the ultimate plan Who are we to argue otherwise?

Anyway, because I do not agree with the idea that the so-called soft path is the

“benign” path, I also cannot say that the impacts of renewable energy sources are necessarily bad, baneful, damaging, dangerous, deleterious, detrimental, evil, or harmful to the environment The question is: What can I say in this book and else-where about renewable energy? I can say that I am biased toward the use of renew-able energy, that I am for Lovins’ soft path and against the hard path But, I qualify this by also stating that renewable energy sources have impacts on the environment, both good and bad, and it is these bad impacts that this book is all about

So, let’s cut to the chase My broad thesis is that renewable energy sources are not the panacea for solving our many pollution problems that they are popularly perceived to be In reality, their adverse environmental impacts can be as strongly negative as the impacts of nonrenewable energy sources Oh, before we begin the discussion, a final word … one of those bottom liners I tend to use On the subject

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of global climate change, the author is sure that things are changing but not entirely sure how Much of the evidence is anecdotal, and there are not enough data to draw solid conclusions When I speak of data, I am referring to some form of irrefutable evidence What we have in the global climate change argument is not always a fail-ure to communicate but instead a situation characterized as underdetermination For example, consider this analogy: If all that we know is that exactly $10 was spent on prunes and apples, and that prunes cost $1 and apples $2, then we know enough to eliminate some possible purchase combinations (e.g., only 5 prunes could not have been purchased), but we would not have enough evidence to know which specific combination of prunes and apples was purchased.

Here’s the real bottom line on global climate change The historical record shows that Earth has a history of cyclical climate change over time Is humankind the cause

of the current changes in global climate? We simply do not know; the jury is still out The causal factors remain to be determined

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Author

Frank R Spellman, PhD, is a retired

assistant professor of environmental health at Old Dominion University, Norfolk, Virginia, and the author of more than 90 books covering top-ics ranging from concentrated animal feeding operations (CAFOs) to all areas

of environmental science and pational health Many of his texts are readily available online, and several have been adopted for classroom use at major universities throughout the United States, Canada, Europe, and Russia; two have been translated into Spanish for South American markets Dr Spellman has been cited in more than 450 publications He serves as a professional expert witness for three law groups and as an incident/accident investigator for the U.S Department

occu-of Justice and a northern Virginia law firm In addition, he consults on homeland rity vulnerability assessments for critical infrastructures, including water/wastewater facilities, and conducts audits for Occupational Safety and Health Administration and Environmental Protection Agency inspections throughout the country Dr Spellman receives frequent requests to co-author with well-recognized experts in various

secu-scientific fields; for example, he is a contributing author to the prestigious text The

Engineering Handbook, 2nd ed Dr Spellman lectures on sewage treatment, water treatment, and homeland security, as well as on safety topics, throughout the country and teaches water/wastewater operator short courses at Virginia Tech in Blacksburg

He earned a BA in public administration, a BS in business management, an MBA, and both an MS and a PhD in environmental engineering

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on which we can draw Our civilization has developed a vast thirst for this energy, as we’ve built billions and billions of machines large and small that all depend on fuel and electricity.

Hartmann (2004)

Oil creates the illusion of a completely changed life, life without work, life for free

… The concept of oil expresses perfectly the eternal human dream of wealth achieved through lucky accident … In this sense, oil is a fairy tale and like every fairy tale a bit of a lie.

—Ryszard Kapuscinski (Polish journalist)

Massive changes in the existence of humanity are imminent The oil shortage? Blame

it all on the Greenies, it is their entire fault There’s something guttural, something personal, about the price of gas.

Steiner (2009)

Renewables can’t save climate.

—Virginian-Pilot (Norfolk, VA), September 24, 2013

ENERGY

Defining energy can be accomplished by providing a technical definition or by a acterization in layman terms Because the purpose of this book is to reach technical readers as well as a wide range of general readers, definitions provided herein and hereafter are best described as technical/nontechnical-based Consider the definition

char-of energy, for example; it can be defined in a number char-of ways In the broad sense, energy means the capacity of something—a person, an animal or a physical system (machine)—to do work and produce change In layman terms, energy is the amount

of force or power that, when applied, can move an object from one position to another

It can also be used to describe someone doing energetic things, such as running, ing, and acting in a lively and vigorous way It is used in science to describe how much potential a physical system has to change It also is used in economics to describe the part of the market where energy itself is harnessed and sold to consumers For our purposes in this text, we simply define energy in technical/nontechnical-based terms

talk-as something that can do work or the capacity of a system to do work

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There are two basic forms of energy: kinetic energy and potential energy Kinetic

energy is energy at work or in motion—that is, moving energy; for example, a car

in motion or a rotating shaft has kinetic energy In billiards, a player gives the cue ball kinetic energy when she strikes the ball with the cue As the ball rolls, it exerts kinetic energy When the ball comes into contact with another ball, it transmits its kinetic energy, allowing the next ball to be accelerated Potential energy is stored energy, such as the energy stored in a coiled or stretched spring or an object stationed above a table A roller coaster has the greatest potential energy when it is stopped at the top of a long drop Another example of potential energy is when a can of carbon-ated soda remains unopened The can is pressurized with gas that is not in motion but that has potential energy When the can is opened, the gas is released and the potential energy is converted to kinetic energy

According to the law of conservation of energy, energy cannot be made or destroyed but can be made to change forms Moreover, when energy changes from one form to another, the amount of energy stays the same Let’s consider an exam-ple of the law of conservation of energy: The initial energy of something is mea-sured The energy then changes from potential (stored) energy to kinetic (moving) and back again After that, the energy is measured again The energy measured at the start is the same as that measured at the end; it will always be the same One caveat to this explanation is that we now know that matter can be made into energy through processes such as nuclear fission and nuclear fusion The law of conserva-tion of energy has therefore been modified or amplified to become the law of con-servation of matter and energy

TYPES OF ENERGY

The many types of energy include the following:

• Kinetic (motion) energy

therefore, coal, nuclear, and hydropower are called energy sources When we fill up

a gas tank, the source might be petroleum or ethanol made by growing and ing corn

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Setting the Stage: The 411 on Energy Basics

Energy sources are divided into two groups—renewable (an energy source that can

be easily replenished) and nonrenewable (an energy source that we are using up and

cannot recreate; petroleum, for example, was formed millions of years ago from the remains of ancient sea plants and animals) In the United States, most of our energy comes from nonrenewable energy sources Coal, petroleum, natural gas, propane, and uranium are nonrenewable energy sources They are used to make electricity, to heat our homes, to move our cars, and to manufacture all kinds of products Renewable and nonrenewable energy sources can be used to produce secondary energy sources, including electricity and hydrogen Renewable energy sources include the following:

Renewable energy (energy sources that can be easily replenished) is the focus

of this text Unfortunately (depending on your point of view), nonrenewable energy sources on Earth are available in limited quantity and may vanish within the next

100 years Moreover, keep in mind that nonrenewable sources are not environmental

friendly and can have serious effects on our health Notwithstanding the mental and health impacts of using nonrenewable energy sources, it is important to point out both sides of the argument—that is, the benefits derived and non-benefits obtained by using these sources

environ-NONRENEWABLE ENERGY

B enefits

• Nonrenewable sources are easy to use

• A small amount of nuclear energy will produce a large amount of power

• Nonrenewable energy sources have little competition

• Nonrenewable energy sources are relatively inexpensive when converting from one type of energy to another

n on -B enefits

• Nonrenewable sources will expire some day

• The speed at which such resources are being used can bring about serious environmental changes

• Nonrenewable sources release toxic gases in the air when burned and can further exacerbate ongoing, cyclical climate change

• Because nonrenewable sources are becoming scarcer, prices of these sources will begin to soar

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consid-• Renewable energy helps stimulate the economy and create job opportunities.

• Renewable energy sources enable the country to become energy dent, not having to rely on foreign (often hostile) sources

indepen-n on -B enefits

• Initial set-up costs of renewable energy sources are quite high

• Solar energy is limited to daytime availability and cannot be obtained ing the night or a rainy season

dur-• Geothermal energy can bring toxic chemicals from beneath the surface of the earth up to the top and can cause environmental damage

• Hydroelectric dams are expensive to build and can affect natural flow and wildlife

• Wind energy production requires high winds and must be sited properly

to be effective Also, wind turbines are tall structures that can affect bird populations

ENERGY USE IN THE UNITED STATES

Use of energy in the United States is shared by four major sectors of the economy Each end-use sector consumes electricity produced by the electric power sector (EIA, 2013):

• Commercial—18% (buildings such as offices, malls, stores, schools,

hospi-tals, hotels, warehouses, restaurants, places of worship, and more)

• Industrial—32% (facilities and equipment used for manufacturing,

agricul-ture, mining, and construction)

• Residential—21% (homes and apartments)

• Transportation—28% (vehicles that transport people or goods, such as

cars, trucks, buses, motorcycles, trains, subways, aircraft, boats, barges, and even hot-air balloons)

Primary energy consumption in the United States was almost three times greater in

2012 than in 1949 In all but 18 of the years between 1949 and 2012, primary energy consumption increased over the previous year

The year 2009 provided a sharp contrast to the historical trend, in part due to the economic recession Real gross domestic product (GDP) fell 2% compared to 2008, and energy consumption declined by nearly 5%, the largest single year decline since

1949 Decreases occurred in all four of the major end-use sectors: commercial (3%), industrial (9%), residential (3%), and transportation (3%) (EIA, 2013)

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MEASURING ENERGY

Energy can be measured That is, the amount of energy a thing has can be given

a number As in other kinds of measurements, there are measurement units The units of measurement for measuring energy are used to make the numbers under-standable and meaningful The SI unit for both energy and work is the joule (J) It

is named after James Joule, who discovered that heat is a type of energy In terms

of SI units, 1 joule = 1 newton-meter, and 1 joule = 1 kg⋅m2⋅s–2 The energy unit

of measurement for electricity is the kilowatt-hour (kWh); 1 kWh is equivalent to 3,600,000 J (3600 kJ or 3.6 MJ) A common way to express energy is in the British thermal unit (Btu) (see Table 1.1) A Btu is the amount of heat energy it takes to raise the temperature of 1 pound of water by 1°F at sea level

to a gear train to power a pump or other machine, but today the primary purpose

of wind turbines is to produce electricity Solar power can be used to heat water to purify it and directly to produce steam which in turn powers a turbine to perform mechanical functions Solar power can also be used to produce photovoltaic (PV) electrical energy Even biomass liquid fuels can be used to power boilers that pro-duce steam to power turbines connected to generators to produce electricity In addition, waste off-gases or exhaust from various machines such as gas turbine engines can be used to heat boilers

TABLE 1.1

Btu Conversion Factors

Energy Source Physical Units and Btu (Weighted Averages)

Natural gas 1 cubic foot = 1028 Btu = 0.01 therms

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The actual production of steam for powering turbines for energy conversion is

accomplished by machines called heat engines A few heat engine examples include

an automobile engine that converts the chemical energy of gasoline into the cal energy of a piston and camshaft or the turbine in an electrical generating plant that converts heat into shaft work to run a generator which, in turn, produces electrical power The heat engines of interest to us in this text are the Rankine cycle (or vapor cycle) and the Stirling cycle (or gas cycle) heat engines (Hinrichs and Kleinbach, 2006)

mechani-HEAT ENGINES

A heat engine is a device that converts thermal energy to mechanical output The thermal energy input is called heat, and the mechanical output is called work

Typically, heat engines run on a specific thermodynamic cycle Heat engines can

be open to the atmospheric air (open cycle) or sealed and closed off to the outside (closed cycle) The driving agent of a heat engine is a temperature differential That

is, heat engines convert heat energy to mechanical work by exploiting the ture gradient between a hot “source” and a cold “sink” (see Figure 1.1) Heat is trans-ferred from the source, through the “working body” of the engine, to the sink, and in this process some of the heat is converted into work by exploiting the properties of a gas or liquid (the working substance) The lower the sink temperature or the higher the source temperature, the more work is available from the heat engine

tempera-Q H

W

Q L

where

Q H = Heat energy taken from the high-temperature system.

Q L = Heat energy delivered to the low-temperature system.

W = Work.

T H = Absolute temperature of heat source.

T L = Absolute temperature of cold sink

Hot source (T H)

Cold sink (T L)

FIGURE 1.1 Heat engine diagram.

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After doing work, the working substance can be either exhausted into the ronment or sent back to the heat source to start the cycle over If the working sub-stance is returned to its initial state (gas or liquid), there has been no change in its total energy Consequently, from the first law of thermodynamics, the total energy

envi-of a system can be increased by doing work on it or by adding heat, and the total work done by the system is just equal to the heat added (i.e., heat in minus heat out) The heat source may be direct solar radiation, geothermal steam, geothermal water, ocean water heated by the sun, combustion fuel, or nuclear energy The two types of heat engines that are most commonly associated with renewable energy processes such as solar power and geothermal energy are the Rankine cycle and Stirling engines

R ankine C yCle H eat e ngine

Figure 1.2 illustrates the four processes as they occur in a closed-cycle Rankine cycle heat engine The expansion can be accomplished through a cylinder with a piston, as in the locomotives one still sees in the old western movies or through a turbine In the Rankine cycle heat engine, as described for turbine use, the working fluid changes state and is also called a vapor gas (i.e., hot air; not to be confused with fuel natural gas) cycle Rankine cycle engines are all external combustion devices, such as external combustion gas turbine engines widely used in units for electrical generating stations

As shown in the figure below, the first phase pumps the working fluid from low

to high pressure; because the fluid is a liquid at this stage, the pump requires little input energy In the second phase, the high-pressure liquid enters a boiler, where it

is heated at constant pressure by an external heat source to become a dry saturated vapor In the third phase, the dry saturated vapor expands through the turbine, thus generating power In the process, both the temperature and pressure of the vapor are lowered, and it is possible that some condensation may occur In the final phase, the wet vapor enters a condenser, where it is condensed at a constant pressure and temperature to become a saturated liquid The pressure and temperature of the con-denser are fixed by the temperature of the cooling coils as the fluid is undergoing a phase change

Liquid (for reuse)

FIGURE 1.2 The four processes of the Rankine cycle.

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s tiRling C yCle H eat e ngine

The Stirling cycle heat engine consists of isothermal compression, isometric heat addition, isothermal expansion, and isometric heat rejection It operates by cyclical compression and expansion of air or other gas, the working fluid, at different tempera-ture levels such that there is a net conversion of heat energy to mechanical work Like

a steam engine, the Stirling heat engine’s heat flows in and out through the engine wall The Stirling engine is noted for its high efficiency (results from heat regenera-tion), quiet operation, and the ease with which it can use almost any heat source This compatibility with renewable energy sources has become increasingly significant as the price of conventional fuels rises and also in light of concerns such as climate change and peak oil An example of this compatibility with renewable energy sources

is evident when Stirling engines are placed at the focus of parabolic mirrors, where they can convert solar energy to electricity with an efficiency better than that of non-concentrated photovoltaic cells and as compared to concentrated photovoltaics

THOUGHT-PROVOKING QUESTIONS

1.1 Is nuclear energy considered to be renewable energy?

1.2 What are the economic ramifications of running out of crude oil? Explain1.3 Will the crude oil crisis come about gradually or suddenly? Explain

1.4 An economy based on renewable energy will help in our ongoing fight to reduce pollution Explain

1.5 Name 15 products produced by oil that we could get along without

REFERENCES AND RECOMMENDED READING

Anon (1998) Excerpts from Statements in Court The New York Times, January 9, p B4 Anon (2009) Napolitano tells it like it isn’t The Washington Times, March 29 (http://www.wash-

ingtontimes.com/news/2009/mar/29/ tell-it-like-it-is-man-caused-disasters-is-napolit/).

Callen, H.B (1985) Thermodynamics and an Introduction to Thermostatistics, 2nd ed New

York: John Wiley & Sons.

CRS (2006) Chemical Facility Security, CRS Report for Congress Washington, DC:

Congressional Research Service, The Library of Congress.

EIA (2009) What Is Energy? Explained Washington, DC: U.S Energy Information Administration

(http://tonto.eia.doe.gov/energyexplained/print.cfm?page=about_sources_of_energy).

EIA (2013) Use of Energy in the United States Explained Washington, DC: U.S

Energy Information Administration (http://tonto.eia.doe.gov/energyexplained/print cfm?page=us_energy_use).

Feynman, R.P., Leighton, R.B., and Sands, M (1963) The Feynman Lectures on Physics New

York: Addison-Wesley.

Haimes, Y.Y (2004) Risk Modeling, Assessment, and Management, 2nd ed New York: John

Wiley & Sons, p 699.

Halliday, D and Resnick, R (1978) Physics, 3rd ed New York: John Wiley & Sons.

Hartmann, T (2004) The Last Hours of Ancient Sunlight: Revised and Updated New York:

Broadway Books.

Hinrichs, R.A and Kleinbach, M (2006) Energy: Its Use and the Environment, 4th ed

Belmont, CA: Brooks/Cole.

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Kroemer, H and Kittel, C (1980) Thermal Physics, 2nd ed New York: W.H Freeman.

Lindsey, H (2001) Vocabulary of hate: Hal Lindsey details deceptive language of Islam’s

leaders WorldNetDaily.com, November 7 (http://www.freerepublic.com/focus/f-news/

565507/posts).

NREL (2009) Energy Storage Washington, DC: National Renewable Energy Laboratory

(http://www.nrel.gov/vehiclesandfuels/energystorage/battery_types.html).

Organ, A.J (1992) Thermodynamics and Gas Dynamics of the Stirling Cycle Machine

London: Cambridge University Press.

Organ, A.J (1997) The Regenerator and the Stirling Engine New York: John Wiley & Sons OSHA (2007) Combustible Dust National Emphasis Program, CPL 03-00-006 Washington,

DC: U.S Department of Labor (www.osha.gov/pls/oshaweb/owadisp.show_document? p_table=DIRECTIVES&p_id=3729).

Spellman, F.R (1997) A Guide to Compliance for Process Safety Management/Risk Management Planning (PSM/RMP) Lancaster, PA: Technomic.

Spellman, F.R and Drinan, J.E (2001) Electricity Boca Raton, FL: CRC Press.

Steiner, C (2009) $20 Per Gallon: How the Inevitable Rise in the Price of Gasoline Will Change Our Lives for the Better New York: Grand Central Publishing.

U.S Congress (2005) Country Reports on Terrorism, http://www.state.gov/j/ct/rls/crt/ USDOE (1992) DOE Fundamentals Handbook Vol 1 Electrical Science Washington, DC:

U.S Department of Energy.

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Eagles Don’t Dare

The wind goeth toward the south, and turneth about unto the north; it whirleth about continually, and the wind returneth again.

—Ecclesiastes 1:6 The Good, Bad, and Ugly of Wind Energy

Good: As long as Earth exists, the wind will always exist The energy in the winds

that blow across the United States each year could produce more than 16 billion GJ of electricity—more than one and one-half times the electricity consumed in the United States in 2000.

Bad: Turbines are expensive Wind doesn’t blow all the time, so they have to be part of

a larger plan Turbines make noise Turbine blades kill birds.

Ugly: Some look upon giant wind turbine blades cutting through the air as grotesque

scars on the landscape, as visible polluters.

The bottom line: Do not expect Don Quixote, mounted in armor on his old nag,

Rocinate, with or without Sancho Panza, to lead the charge to build those windmills Instead, expect—you can count on it, bet on it, and rely on it—that the charge will be made by the rest of us to satisfy our growing, inexorable need for renewable energy What other choice do we have?

Recent Headlines on Wind Turbines

“Wind Turbines: A Different Breed of Noise?” (Seltenrich, 2014)

“Wind Turbine Health Effects: Are Wind Turbines Really Unhealthy for Humans?” (Casey, 2012a)

“How Noisy is a Wind Turbine?” (Casey, 2012b)

“U.S to Allow Eagle Deaths—To Aid Wind Power” (Cappiello, 2013a)

“Eagle Deaths at Wind Farms Glossed Over” (Cappiello, 2013b)

* Adapted from Spellman, F.R and Whiting, N.E., Environmental Science and Technology, Government

Institutes Press, Lanham, MD, 2006.

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manifestations are obvious, the importance of the dynamic state of our atmosphere

is much less obvious The constant motion of the atmosphere of Earth is both

hori-zontal (wind) and vertical (air currents) This air movement is the result of thermal

energy produced from heating of the surface of the Earth and the air molecules above Because of differential heating of the surface of the planet, energy flows from the equator poleward

The energy resources contained in the wind in the United States are well known and mapped in detail (Hanson, 2004) It is clear that air movement plays a critical role in transporting the energy of the lower atmosphere, bringing the warming influ-ences of spring and summer and the cold chill of winter, and wind and air currents are fundamental to how nature functions Still, though, the effects of air movements

on our environment are often overlooked All life on Earth has evolved or has been sustained with mechanisms dependent on air movement; for example, pollen is car-ried by the winds for plant reproduction, animals sniff the wind for essential informa-tion, and wind power was the motive force during the earliest stages of the Industrial Revolution We can also see other effects of winds Wind causes weathering (erosion)

of the Earth’s surface, wind influences ocean currents, and the wind carries air lutants and contaminants such as radioactive particles that impact our environment

pol-In addition to the natural air movement processes described above, air movement has been harnessed by the wind industry and is playing a pivotal role in achieving a balanced energy mix in the United States In 2012, wind energy was—for the first time ever—the number one source of new electricity generation capacity More wind power capacity was installed in the United States than any other form of power gen-eration (Siemens, 2014)

In practical terms, a wind turbine is defined as a device that converts kinetic energy from the wind into electrical power In esthetic and thoughtful terms, a wind turbine

is described as a clean, presentable structure that benefits the environment by ing a supply of clean and renewable electricity When we look closer at wind turbines,

generat-we often find there are impacts associated with them, many of which are described in this chapter, but first we present the basics of air or wind movement and wind turbine operation in order to properly prepare the reader for the material that follows

DID YOU KNOW?

Wind speed is generally measured in meters per second (m/s), but Americans usually think in terms of miles per hour (mph) To convert m/s to mph, a good rule of thumb is to double the m/s value and add 10%

DID YOU KNOW?

Wind power consists of turning energy from the wind to other energy forms There are different ways to harness it; for example, windmills produce mechan-ical energy to generate electricity

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Wind Power: Where Eagles Don’t Dare

WIND POWER BASICS

A ir in M otion *

In all dynamic situations, forces are necessary to produce motion and changes in motion—winds and air currents The air (made up of various gases) of the atmo-sphere is subject to two primary forces: gravity and pressure differences from tem-

perature variations Gravity (gravitational forces) holds the atmosphere close to the

Earth’s surface Newton’s law of universal gravitation states that every body in the universe attracts another body with a force equal to

r

where F is the magnitude of the gravitational force between the two bodies, G is the

gravitational constant ≈ 6.67 × 10–11 N (m2/kg2), m1 and m2 are the masses of the two

bodies, and r is the distance between the two bodies.

The force of gravity decreases as an inverse square of the distance between the two bodies Thermal conditions affect density, which in turn affects vertical air motion and planetary air circulation (and how air pollution is naturally removed from the atmosphere) Although forces acting in other directions can overrule gravi-tational force, gravity constantly acts vertically downward, on every gas molecule, which accounts for the greater density of air near the Earth

Atmospheric air is a mixture of gases, so the gas laws and other physical ciples govern its behavior The pressure of a gas is directly proportional to its temperature Pressure is force per unit area (pressure = force/area), so a tempera-ture variation in air generally gives rise to a difference in pressure of force This difference in pressure resulting from temperature differences in the atmosphere creates air movement—on both large and local scales This pressure difference corresponds to an unbalanced force, and when a pressure difference occurs the air moves from a high- to a low-pressure region In other words, horizontal air move-

prin-ments (called advective winds) result from temperature gradients, which give rise

to density gradients and subsequently pressure gradients The force associated with

these pressure variations (pressure gradient force) is directed at right angles to (perpendicular to) lines of equal pressure (called isobars) and is directed from high

to low pressure

Localized air circulation gives rise to thermal circulation (a result of the

relation-ship based on a law of physics whereby the pressure and volume of a gas are directly related to its temperature) A change in temperature causes a change in the pressure and volume of a gas With a change in volume comes a change in density (density

= mass/volume), so regions of the atmosphere with different temperatures may have different air pressures and densities As a result, localized heating sets up air motion and gives rise to thermal circulation

* Adapted from Spellman, F.R and Bieber, R., The Science of Renewable Energy, CRC Press, Boca

Raton, FL, 2011.

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Once the air has been set into motion, secondary forces (velocity-dependent forces) act These secondary forces are caused by Earth’s rotation (Coriolis force)

and contact with the rotating Earth (friction) The Coriolis force, named after its

discoverer, French mathematician Gaspard Coriolis (1772–1843), is the effect of rotation on the atmosphere and on all objects on the Earth’s surface In the Northern Hemisphere, it causes moving objects and currents to be deflected to the right; in the Southern Hemisphere, it causes deflection to the left, because of the Earth’s rota-tion Air, in large-scale north or south movements, appears to be deflected from its expected path That is, air moving poleward in the Northern Hemisphere appears to

be deflected toward the east; air moving southward appears to be deflected toward the west

Friction (drag) can also cause the deflection of air movements This friction (resistance) is both internal and external The friction of molecules generates internal friction, and external friction is caused by contact with terrestrial surfaces The mag-nitude of the frictional force along a surface is dependent on the air’s magnitude and speed, and the opposing frictional force is in the opposite direction of the air motion

WIND ENERGY *

Wind energy is power produced by the movement of air Since early recorded tory, people have been harnessing the energy of the wind to, for example, mill grain and pump water Wind energy propelled boats along the Nile River as early as 5000

his-BC By 200 BC, simple windmills in China were pumping water, and windmills with woven reed sails were grinding grain in Persia and the Middle East

The use of wind energy spread around the world, and by the 11th century people

in the Middle East were using windmills extensively for food production; returning merchants and crusaders carried this idea back to Europe The Dutch refined the windmill and adapted it for draining lakes and marshes in the Rhine River delta When settlers took this technology to the New World in the later 19th century, they used windmills to pump water for farms and ranches and, later, to generate electricity for homes and industry The first known wind turbine designed to pro-duce electricity was built in 1888 by Charles F Brush, in Cleveland, Ohio; it was a 12-kW unit that charged batteries in the cellar of a mansion The first wind turbine used to generate electricity outside of the United States was built in Denmark in

1891 by Poul la Cour, who used electricity from his wind turbines to electrolyze water to make hydrogen for the gas lights at the local schoolhouse By the 1930s and 1940s, hundreds of thousands of wind turbines were being used in rural areas

of the United States that were not yet being served by the grid The oil crisis in the 1970s created a renewed interest in wind energy, until the U.S government stopped giving tax credits

* Adapted from EERE, History of Wind Energy, Energy Efficiency and Renewable Energy, U.S

Department of Energy, Washington, DC, 2005 (http://www1.eere.energy.gov/windandhydro/wind_ history.html).

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Today, several hundred thousand windmills are in operation around the world, many of which are used for pumping water The use of wind energy as a pollution-free means of generating electricity on a significant scale is attracting the most interest in the subject today As a matter of fact, due to current and pending short-ages and high costs of fossil fuels to generate electricity, as well as the green move-ment toward the use of cleaner fuels, wind energy is the world’s fastest growing energy source and could power industry, businesses, and homes with clean, renew-able electricity for many years to come In the United States, wind-based electric-ity generating capacity has increased markedly since the 1970s Today, though,

it still represents only a small fraction of total electric capacity and consumption (see Table 2.1), despite the advent of $4/gal gasoline, increases in the cost of elec-tricity, high heating and cooling costs, and worldwide political unrest or uncer-tainty in oil-supplying countries Traveling the wind corridors of the United States (primarily Arizona, New Mexico, Texas, Missouri, and north through the Great Plains to the Pembina Escarpment and Turtle Mountains of North Dakota) gives some indication of the considerable activity and seemingly exponential increase in wind energy development and wind turbine installations; these machines are being installed to produce and provide electricity to the grid

DID YOU KNOW?

We can classify wind energy as a form of solar energy Winds are caused by uneven heating of the atmosphere by the sun, irregularities of the Earth’s sur-face, and the rotation of the Earth As a result, winds are strongly influenced and modified by local terrain, bodies of water, weather patterns, vegetative cover, and other factors The wind flow, or motion of energy when harvested

by wind turbines, can be used to generate electricity

TABLE 2.1

U.S Energy Consumption by Source (2013)

Energy Source

Energy Consumption (quadrillion Btu)

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WIND POWER

The terms wind energy and wind power describe the process by which the wind is

used to generate mechanical power or electricity Wind turbines convert the kinetic energy in the wind into mechanical power This mechanical power can be used for specific tasks (such as grinding grain or pumping water), or a generator can convert this mechanical power into electricity (EERE, 2006a) We have been harnessing the energy of the wind for hundreds of years From old Holland to farms in the United States, windmills have been used for pumping water or grinding grain; today, the modern equivalent of a windmill—a wind turbine—can use the energy of the wind to generate electricity The blades of a wind turbine spin like aircraft propeller blades Wind turns the blades, which in turn spin a shaft connected to a generator to produce electricity (Wind Energy EIS, 2009)

W ind t urbine t ypes

Whether referred to as driven generators, wind generators, wind turbines,

wind-turbine generators , or wind energy conversion systems, modern wind turbines fall

into two basic groups: the horizontal-axis wind turbine (HAWT), like the traditional farm windmills used for water pumping, and the vertical-axis wind turbine (VAWT), like the eggbeater-style, Darrieus rotor model, named after its French inventor, the only vertical-axis machine with any commercial success Wind hitting the vertical

blades, called aerofoils, generates lift to create rotation No yaw (rotation about

verti-cal axis) control is needed to keep them facing into the wind The heavy machinery in the nacelle (cowling) is located on the ground Blades are closer to the ground where wind speeds are lower Most large modern wind turbines are horizontal-axis turbines; therefore, this type is highlighted and described in detail in this text

H orizontAl -A xis W ind t urbines

Wind turbines are available in a variety of sizes and power ratings Utility-scale turbines range in size from 100 kW to as large as several megawatts Horizontal-axis wind turbines typically have two or three blades Downwind horizontal-axis wind

DID YOU KNOW?

Whenever wind energy is being considered as a possible source of renewable energy it is important to consider the amount of land area required, accessibil-ity to generators, and aesthetics

DID YOU KNOW?

Groups of wind turbines are located in what is called a wind farm or a wind

park (see Figure 2.1)

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turbines have a turbine with the blades behind (downwind from) the tower No yaw control is needed because they naturally orient themselves in line with the wind; however, these downwind HAWTs experience a shadowing effect, in that when a blade swings behind the tower the wind it encounters is briefly reduced and the blade flexes Upwind HAWTs usually have three blades in front (upwind) of the tower These upwind wind turbines require a somewhat complex yaw control to keep them facing into the wind They operate more smoothly and deliver more power and thus are the most commonly used modern wind turbines The largest machine has blades that span more than the length of a football field, stands 20 building stories high, and produces enough electricity to power 1400 homes

Inside the HAWT

Basically, a horizontal-axis wind turbine consists of three main parts: a turbine, a nacelle (the cover housing that houses all of the generating components in a wind tur-bine, including the generator, gearbox, drive train, and brake assembly), and a tower Several other important parts are contained within the tower and nacelle, including anemometer, blades, brake, controller, bear box, generator, high-speed shaft, low-speed shaft, pitch, rotor, tower, wind direction, wind vane, yaw drive, and yaw motor (see Figure 2.2)

FIGURE 2.1 Wind turbines at the Tehachapi Pass Wind Farm in California Wind

develop-ment in the Tehachapi Pass began in the early 1980s, and this is one of the first large-scale wind farms installed in the United States.

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WIND TURBINE COMPONENTS

Anemometer—This device measures the wind speed and transmits wind speed data to the controller

Blades—Wind blowing over the two or three blades causes the blades to lift and rotate; they capture the kinetic energy of the wind and help the turbine rotate

Brake—A disc brake can be applied mechanically, electrically, or cally to stop the rotor in emergencies

hydrauli-Controller—The controller starts up the machine at wind speeds of about 8 to

16 mph and shuts off the machine at about 55 mph Turbines do not operate

at wind speeds above about 55 mph because they might be damaged by the high winds

Gear box—Gears connect the low-speed shaft to the high-speed shaft and increase the rotational speeds from about 30 to 60 rotations per minute (rpm) to about 1000 to 1800 rpm, the rotational speed required by most generators to produce electricity The gear box is a costly (and heavy) part

of the wind turbine, and engineers are exploring direct-drive generators that operate at lower rotational speeds and do not require gear boxes

60-hertz alternating-current electricity

High-speed

Wind vane

Controller AnemometerGenerator

Gear box

Low-speed shaft Pitch

FIGURE 2.2 Horizontal-axis wind turbine components.

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High-speed shaft—The shaft that drives the generator

Low-speed shaft—A shaft that turns at about 30 to 60 rotations per minute

Nacelle—Unit that sits atop the tower and contains the gearbox, generator, low- and high-speed shafts, controller, and brake

Pitch—Blades are turned, or pitched, out of the wind to control the rotor speed and keep the rotor turning in winds that are too high or too low to produce electricity

Rotor—Comprised of the blades and the hub

Tower—Made from tubular steel, concrete, or steel lattice Because wind speed increases with height, taller towers enable turbines to capture more energy and generate more electricity

Wind direction—An upwind turbine operates facing into the wind; other bines are designed to run downwind, facing away from the wind

tur-Wind vane—Measures wind direction and communicates with the yaw drive

to orient the turbine properly with respect to the wind

Yaw drive—In upwind turbines, this is used to keep the entire nacelle and thus the rotor facing into the wind as the wind direction changes Downwind turbines do not require a yaw drive, as the wind blows the rotor downwind

Yaw motor—Powers the yaw drive

WIND ENERGY SITE EVALUATION IMPACTS

Site evaluation phase activities, such as monitoring and testing, are temporary and are conducted at a smaller scale than those at the construction and operation phases Potential impacts of these activities are presented below by type of affected resource The impacts described are for typical site evaluation and exploration activities, such

as ground clearing (removal of vegetative cover), vehicular and pedestrian traffic, borings for geotechnical surveys and guy wire installation, and positioning of equip-ment, such as meteorological towers If excavation of road construction is necessary during this phase, potential impacts would be similar in character to those for the construction phase, but generally of smaller magnitude

A ir Q uAlity

Impacts on air quality during monitoring and testing activities would be limited to porary and local generation of vehicle emissions and fugitive dust These impacts are unlikely to cause an exceedance of air quality standards or to impact climate change

tem-DID YOU KNOW?

During rotation of the nacelle, the cables inside the tower can twist, with the cables becoming more and more twisted if the turbine keeps turning in the same direction, which can happen if the wind keeps changing in the same direction The wind turbine is therefore equipped with a cable twist counter, which notifies the controller that it is time to straighten the cables (Khaligh and Onar, 2010)

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C ulturAl r esourCes

Surface disturbance is minimal during the site evaluation phase, and cultural resources buried below the surface are unlikely to be affected Cultural material present on the surface could be disturbed by vehicular traffic, ground clearing, and pedestrian activity (including collection of artifacts) Monitoring and testing activi-ties could affect areas of interest to Native Americans depending on the physical placement or level of visual intrusion Surveys conducted during this phase to evalu-ate the presence or significance of cultural resources in the area would assist devel-opers in designing the project to avoid or minimize impacts on these resources

e CologiCAl r esourCes

Impacts on vegetation, wildlife habitat, and aquatic habitat would be minimal during site monitoring and testing because of the limited nature of activities The introduc-tion and spread of invasive vegetation could occur as a result of vehicular traffic Surveys conducted during this phase to evaluate the presence and/or significance of ecological resources in the area would assist developers in designing the project to avoid or minimize impacts on these resources

W Ater r esourCes

There likely would have minimal impact on water resources, local water quality, water flows, and surface water/groundwater interactions Very little water would likely be used during the site evaluation phase Any water required could be trucked

in from offsite

l And u se

Monitoring and testing activities would likely result in temporary and localized impacts on land use These activities could create a temporary disturbance to wild-life and cattle in the immediate vicinity of the monitoring/testing site while workers are present; however, monitoring equipment is unlikely to change land-use patterns over a longer period of time Although a buffer area may be established around equipment to protect the public, wildlife, and the equipment, access to the area for continued recreational use would not be affected There could be visual impacts, though, from the presence of equipment and access roads, potentially impacting the recreational experience Monitoring and testing activities are unlikely to affect min-ing activities, military operations, or aviation

s oils And g eologiC r esourCes

Surface disturbance and use of geologic materials are minimal during the site ation phase, and soils and geologic resources are unlikely to be affected These activ-ities would also be unlikely to activate geological hazards or increase soil erosion Borings for soil testing and geotechnical surveys provide useful site-specific data on these resources Surface effects from pedestrian and vehicular traffic could occur in areas that contain special (e.g., cryptobiotic) soils

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