Energy Resources

Energy  What is Energy ? Many of us would answer…. electricity orgasoline or maybe nuclear power

Energy  What is Energy ? For many people in LDCs energy is… fuel wood

Energy  fuel wood In LDCs used for cooking and heating In LDCs used for cooking and heating

Energy  fuel wood The “other” energy crisis The “other” energy crisis A major problem in LDCs A major problem in LDCs

fuel wood fuel wood  The “other” energy crisis As population grows As population grows the need for fuel wood energy grows

fuel wood fuel wood  The “other” energy crisis energy crisis trees shrubs & bushes grasses crop residues dried dung

trees shrubs & bushes grasses crop residues dried dung The demand for fuel wood is resulting in soil erosion, soil nutrient depletion, and landdegradation land degradation

Energy  fuel wood The “other” energy crisis The “other” energy crisis A major problem in LDCs A major problem in LDCs

 In MDCs, abundant energy is vital to society Energy  Modern industrial culture is energy intensive

 Human cultural evolution has been accompanied by has been accompanied by Energy & Culture Increasingly powerful energy sources Increasingly powerful energy sources Increased per capita energy utilization Increased per capita energy utilization

 Hunter-gatherer society Energy & Culture human muscle power & fire human muscle power & fire  Agricultural society domesticated draft animals domesticated draft animals wind & water power wind & water power

Energy & Culture  Early industrial society coal energy – fossil fuel coal energy – fossil fuel steam engines steam engines

Energy & Culture  Modern industrial society oil & natural gas energy – fossil fuels oil & natural gas energy – fossil fuels internal combustion engines internal combustion engines electrical energy electrical energy nuclear energy nuclear energy

Time Period U.S. Energy Sources Primary Energy Source Pre Fuel Wood  From 1850 to 1900 the use of fire wood decreased as the use of coal increased

Time Period U.S. Energy Sources Primary Energy Source Coal  The use of oil grew during the first half of the 20 th century

Time Period U.S. Energy Sources Primary Energy Source present Oil  During the second half of the 20 th century, oil use surpassed coal use

 The United States has about 6% of world population U.S. Energy Use but we use about one-third of the world’s energy

 High energy use does contribute to a high standard of living U.S. Energy Use but much of our energy is used wastefully  The U.S. is an energy GLUTTON

 We can maintain our standard of living U.S. Energy Use but reduce our energy use through efficiency & conservation

Energy efficiency & conservation  Doing the same work, but using less energy  Our best energy “source”

 Reduces use of fossil fuels Energy efficiency & conservation  Reduces pollution  Reduces release of greenhouse gases

 Prolongs supplies of fossil fuels  Reduces need for new energy plants Energy efficiency & conservation  Allows more time for development of alternative energies

Energy efficiency & conservation  Saves money  Improves our balance of trade  Reduces reliance on imported oil

1973 OPEC Oil Embargo U. S. Reliance On Imported Oil OPECOPECOPECOPEC rganization of etroleum xporting ountries  Reduced availability of crude oil

 Sharp increase in crude oil prices U. S. Reliance On Imported Oil 1973 OPEC Oil Embargo gasoline, home heating oil diesel, and  Prices for sharply increased

 Rapid increases in costs of consumer products 1973 OPEC Oil Embargo  Rapid increase in overall cost of living  Period of double-digit inflation

 Gasoline shortages 1973 OPEC Oil Embargo  Long lines at gasoline stations  Growing popularity of smaller, fuel-efficient autos

 National concern for energy conservation and energy independence 1973 OPEC Oil Embargo  President Carter called the energy crisis “the moral equivalent of war”

 The Carter administration increased federal support for alternative energy research and development 1973 OPEC Oil Embargo

 Unfortunately, federal support for alternative energy research and development declined after the Carter administration U. S. Reliance On Imported Oil  The U.S. is now more dependent on imported oil than it was in 1973

Energy Use of Fossil Fuels  Coal  Petroleum  Natural Gas

Use of Fossil Fuels Energy  Currently, our largest energy source  Large-scale use for only about 200 years

Use of Fossil Fuels Energy  Large-scale use will decline in the future decline in the future Decreasing supplies Decreasing supplies

Use of Fossil Fuels Energy  Large-scale use will decline in the future decline in the future Increasing costs Increasing costs

Use of Fossil Fuels Energy  Large-scale use will decline in the future decline in the future Adverse environmental impacts Adverse environmental impacts

“From the perspective of a 10,000 year time span, human utilization of fossil fuels will seem like a brief, toxic fire aboard a spaceship” Use of Fossil Fuels

Time Present years years years years Use of Fossil Fuels

“From the perspective of a 10,000 year time span, human utilization of fossil fuels will seem like a brief, toxic fire aboard a spaceship” Use of Fossil Fuels

Fossil fuels are a nonrenewable resource Use of Fossil Fuels  Nonrenewable – no more of the resource can be obtained within a useful time frame

Fossil fuels are a nonrenewable resource Use of Fossil Fuels  Geologic formation occurred over millions of years

Reliance on fossil fuels is non-sustainable Use of Fossil Fuels  Nonrenewable, finite supply  Exhaustion of supply will deprive future generations deprive future generations

Reliance on fossil fuels is non-sustainable Use of Fossil Fuels  Exhaustion of supply will deprive future generations deprive future generations Energy resource Energy resource Synthetic base Synthetic base Lubricants Lubricants

Reliance on fossil fuels is non-sustainable Use of Fossil Fuels  Pollution from use may affect future generations affect future generations Global Climate Change Global Climate Change Acid Precipitation Acid Precipitation Chemical Pollution Chemical Pollution

Reliance on fossil fuels is non-sustainable Use of Fossil Fuels  To work toward a sustainable society, we must make the transition to renewable energy sources

United States Energy Sources Use of Fossil Fuels  The U.S. is heavily dependent on fossil fuels  Approximately 85% of U.S. energy

United States Energy Sources Use of Fossil Fuels  Petroleum or oil is the largest single source of U.S. energy  Approximately 40% of U.S. energy

United States Energy Sources Use of Fossil Fuels - Approximately 20% of U.S. energy - Approximately 25% of U.S. energy  Natural Gas  Coal

United States Energy Sources Use of Fossil Fuels  Approximately 15% of U.S. energy comes from all other sources nuclear nuclear hydro hydro solar solar wind wind geothermal geothermal other other

United States Energy Sources Use of Fossil Fuels Oil 40% Natural Gas 25% Gas 25% Coal 20% Non Fossil Fuel 15%

 Total Reserves – the amount left to be recovered Use of Fossil Fuels  Known Reserves – have already been found and quantity estimated  Suspected Reserves – thought to exist, but not yet found, quantity uncertain

Use of Fossil Fuels  Suspected Reserves – thought to exist, but not yet found, quantity uncertain  All the “easy” reserves have been found  Suspected reserves will be in remote locations and will be difficult and expensive to recover

 How long will fossil fuel reserves last ? Use of Fossil Fuels  Uncertainties in estimates due to unknown quantities of suspected reserves unknown quantities of suspected reserves will rate of use increase or decrease will rate of use increase or decrease

 How long will fossil fuel reserves last ? Use of Fossil Fuels  Petroleum – the smallest reserves at current rate of use, reserves may last at current rate of use, reserves may last 40 – 50 years

 How long will fossil fuel reserves last ? Use of Fossil Fuels  Petroleum – the smallest reserves yet the one we use the most yet the one we use the most most urgent need to find a replacement most urgent need to find a replacement

 How long will fossil fuel reserves last ? Use of Fossil Fuels  Natural Gas – larger reserves than oil at current rate of use, reserves may last at current rate of use, reserves may last 60 – 80 years

 How long will fossil fuel reserves last ? Use of Fossil Fuels  Natural Gas – larger reserves than oil the “cleanest” fossil fuel the “cleanest” fossil fuel likely that rate of use will increase likely that rate of use will increase

 How long will fossil fuel reserves last ? Use of Fossil Fuels  Coal – the largest reserves at current rate of use, reserves may last at current rate of use, reserves may last 200 – 300 years

 How long will fossil fuel reserves last ? Use of Fossil Fuels  Coal – the largest reserves the “dirtiest” of the fossil fuels the “dirtiest” of the fossil fuels undesirable to burn it all undesirable to burn it all

 Reserves are limited Use of Fossil Fuels particularly petroleum particularly petroleum  Use has adverse effects on humans on humans on environment on environment

 What are the “costs” of fossil fuel use ? of fossil fuel use ? Use of Fossil Fuels  Costs in a broad sense includes more than just dollars includes more than just dollars includes negative effects on humans and environment includes negative effects on humans and environment

 What are the “costs” of fossil fuel use ? of fossil fuel use ? Use of Fossil Fuels  Human costs may include death and illness difficult to assign a dollar value difficult to assign a dollar value

 What are the “costs” of fossil fuel use ? of fossil fuel use ? Use of Fossil Fuels  Environmental costs may include ecosystem alteration and degradation difficult to assign a dollar value difficult to assign a dollar value

 What are the “costs” of fossil fuel use ? of fossil fuel use ? Use of Fossil Fuels  Externalization of Costs someone other than direct producer or direct consumer bears the costs someone other than direct producer or direct consumer bears the costs

 What are the “costs” of fossil fuel use ? of fossil fuel use ? Use of Fossil Fuels  Externalization of Costs the “costs” of fossil fuel use are often borne by society as a whole the “costs” of fossil fuel use are often borne by society as a whole

 Stages of Exploitation Use of Fossil Fuels Exploration Exploration Extraction Extraction Processing Processing Transportation Transportation End Use End Use

End Use Costs of Fossil Fuels  the most significant human impacts  the most significant environmental impacts environmental impacts

Costs of Fossil Fuels End Use  Global Climate Change fossil fuel combustion releases CO 2 into the atmosphere fossil fuel combustion releases CO 2 into the atmosphere atmospheric CO 2 traps heat in the atmospheric CO 2 traps heat in the atmosphere – global warming atmosphere – global warming

Costs of Fossil Fuels End Use  Global Climate Change the most serious and important threat from our reliance on fossil fuels the most serious and important threat from our reliance on fossil fuels potential major impacts on life on Earth potential major impacts on life on Earth

Costs of Fossil Fuels End Use  Global Climate Change We will consider this important topic in greater detail later in the semester We will consider this important topic in greater detail later in the semester

Costs of Fossil Fuels End Use  Acid Precipitation Combustion reactions release nitrogen oxides (NOx) Combustion reactions release nitrogen oxides (NOx) Combustion of high sulfur fuels releases sulfur oxides (SOx) Combustion of high sulfur fuels releases sulfur oxides (SOx)

Costs of Fossil Fuels End Use  Acid Precipitation NOx react with atmospheric H 2 O to form HNO 3 – nitric acid NOx react with atmospheric H 2 O to form HNO 3 – nitric acid SOx react with atmospheric H 2 O to form H 2 SO 4 – sulfuric acid SOx react with atmospheric H 2 O to form H 2 SO 4 – sulfuric acid

Costs of Fossil Fuels End Use  Acid Precipitation Adverse effects on forests, aquatic ecosystems, structures, human health Adverse effects on forests, aquatic ecosystems, structures, human health

Costs of Fossil Fuels End Use  Acid Precipitation We will consider this topic in greater detail later in the semester We will consider this topic in greater detail later in the semester

Costs of Fossil Fuels End Use  Chemical Pollution Combustion of fossil fuels results in a variety of chemical pollutants Combustion of fossil fuels results in a variety of chemical pollutants

Costs of Fossil Fuels End Use  Chemical Pollution carbon monoxide (CO) carbon monoxide (CO) heavy metals heavy metals radionuclides radionuclides

Costs of Fossil Fuels End Use  Chemical Pollution hydrocarbons hydrocarbons particulates particulates ozone ozone

Costs of Fossil Fuels End Use  Chemical Pollution polycyclic aromatic hydrocarbons (PAHs) polycyclic aromatic hydrocarbons (PAHs) peroxyacyl nitrates (PANs) peroxyacyl nitrates (PANs)

Costs of Fossil Fuels End Use  Chemical Pollution pollutant release has adverse effects on human and environmental health pollutant release has adverse effects on human and environmental health

Costs of Fossil Fuels End Use  Chemical Pollution We will consider this topic in greater detail later in the semester We will consider this topic in greater detail later in the semester

Costs of Fossil Fuels  There are enormous human and environmental “costs” associated with continued use of fossil fuels

 What alternatives are there to the fossil fuels ? Energy Alternatives Nuclear Power Nuclear Power Renewable Energies Renewable Energies

 Nuclear Fission Nuclear Power Nuclear Power  Nuclear Fusion currently working currently working still experimental still experimental energy from chain reaction of a heavy, radioactive element energy from chain reaction of a heavy, radioactive element energy from combining light elements to form a heavier element energy from combining light elements to form a heavier element

Nuclear Fission Nuclear Fission  Heat is released from the chain reaction of a fissionable radioactive isotope  U 235 is typical fuel

 Heat produces steam to spin a turbine and generator to produce electricity Nuclear Fission Nuclear Fission

The radioactive fuel is contained in the reactor core  The radioactive fuel is contained in the reactor core Nuclear Fission Nuclear Fission  Control rods regulate the rate of the chain reaction

 Control rods absorb neutrons to regulate the chain reaction Nuclear Fission Nuclear Fission

 Chernobyl – workers improperly withdrew the control rods leading to a run away chain reaction Nuclear Fission Nuclear Fission  Chernobyl – the run away chain reaction lead to core meltdown and a steam explosion

 U.S. reactors are housed in containment structures Nuclear Fission Nuclear Fission

 Chernobyl – the reactor did not have a containment structure Nuclear Fission Nuclear Fission  Chernobyl – doubtful that a containment structure could have withstood the steam explosion

 What are the pros and cons of nuclear fission ? Nuclear Fission Nuclear Fission

 Nuclear power has some advantages over fossil fuels Nuclear Fission Nuclear Fission

 PROS relative to fossil fuels Nuclear Fission Nuclear Fission No greenhouse gas emissions No greenhouse gas emissions No acid rain emissions No acid rain emissions No chemical pollution emissions No chemical pollution emissions No strip mining No strip mining No acid mine drainage No acid mine drainage

Nuclear Fission Nuclear Fission  additional PROS A currently working technology A currently working technology Very high energy density Very high energy density Overall good safety record Overall good safety record

What are some of the CONS or negative aspects of nuclear fission ? Nuclear Fission Nuclear Fission

 CONS Risk of accidents -- Chernobyl Risk of accidents -- Chernobyl Nuclear Fission Nuclear Fission Nonrenewable energy source Nonrenewable energy source Limited amount of fissionable isotopes Limited amount of fissionable isotopes

 Not all radioactive isotopes are fissionable – will undergo chain reaction Nuclear Fission Nuclear Fission  U 238 – the abundant isotope of uranium is not fissionable  U 235 – is fissionable, but is a relatively rare isotope of uranium

 Breeder Reactors could expand supply of fissionable material Nuclear Fission Nuclear Fission  Breeder Reactors convert U 238 to Pu 239  The U.S. closed its experimental breeder reactor at Clinch River, TN

 CONS Nuclear Fission Nuclear Fission Potential proliferation of nuclear weapons Potential proliferation of nuclear weapons Concern over possible sabotage Concern over possible sabotage Decommissioning old nuclear plants Decommissioning old nuclear plants Disposal of high-level nuclear wastes Disposal of high-level nuclear wastes

Nuclear Fission Nuclear Fission  What to do with high-level nuclear wastes ?  Some isotopes will remain dangerously radioactive for thousands of years

 The U.S. repository for high-level nuclear wastes is under construction at Yucca Mountain, NV Nuclear Fission Nuclear Fission  The wastes will be buried deep underground

 The Yucca Mountain project is controversial Nuclear Fission Nuclear Fission  Until Yucca Mountain is ready, nuclear plants are storing their wastes on site

 CONS Nuclear Fission Nuclear Fission  High construction costs and long construction time  Low public acceptance & support  Lack of private insurance  Health effects on uranium miners

 Point to Ponder Nuclear Fission Nuclear Fission How do you personally feel about nuclear power in the U.S. ? increase a lot increase a lot increase a little increase a little stay about the same stay about the same decrease a little decrease a little decrease a lot decrease a lot

 Energy from combining light elements to form a heavier element Still an experimental technology Still an experimental technology Energy of sun and stars Energy of sun and stars Much more energy than nuclear fission Much more energy than nuclear fission Nuclear Fusion Nuclear Fusion

 Energy of the solar furnace The sun can fuse hydrogen atoms together to form iron The sun can fuse hydrogen atoms together to form iron Goal of fusion energy on Earth is to fuse hydrogen atoms together to form helium or lithium Goal of fusion energy on Earth is to fuse hydrogen atoms together to form helium or lithium

Nuclear Fusion Nuclear Fusion

 Challenges to Development Nuclear Fusion Nuclear Fusion High ignition temperature High ignition temperature Confining the reaction Confining the reaction

 Challenges to Development Nuclear Fusion Nuclear Fusion High ignition temperature High ignition temperature Multiple powerful lasers focused on a single point in space bring frozen deuterium pellet to ignition temperature

 Challenges to Development Nuclear Fusion Nuclear Fusion Confining the reaction Confining the reaction “magnetic bottle” powerful electromagnets confine reaction in a magnetic field

 Still an experimental technology Nuclear Fusion Nuclear Fusion  Controlled fusion reactions have been achieved  However, the “break-even” point has not yet been reached

 the “break-even” point Nuclear Fusion Nuclear Fusion Energy output equals energy input Energy output equals energy input Energy input – ignition and confinement of reaction Energy input – ignition and confinement of reaction

 the “break-even” point Nuclear Fusion Nuclear Fusion Energy output ______________ Energy input = 1.00

 Potential Pros Nuclear Fusion Nuclear Fusion Enormous amounts of energy Enormous amounts of energy Deuterium isotope of hydrogen is abundant in seawater Deuterium isotope of hydrogen is abundant in seawater No radioactive wastes No radioactive wastes

 Cons Nuclear Fusion Nuclear Fusion Not a currently working technology Not a currently working technology Timetable for commercial development remains uncertain Timetable for commercial development remains uncertain

Renewable Energy Sources

 No single renewable energy source will satisfy all energy needs Renewable Energy Sources  However, combinations of different renewable energies can meet most, if not all, of our energy needs

 The exact combination of renewable energies will depend upon geographic location and the energy application Renewable Energy Sources

 Most renewable energy technologies are sufficiently developed for large scale application Renewable Energy Sources TODAY  We need to hasten the transition away from fossil fuels and toward renewable energy

 Many Pros in common Renewable Energy Sources Renewable – supply will not run out Renewable – supply will not run out Low pollution – including CO 2 Low pollution – including CO 2 Prolong supply of fossil fuels Prolong supply of fossil fuels Compatible with a sustainable society Compatible with a sustainable society

 There are many choices available on the renewable energy “menu” Renewable Energy Sources   There are so many choices available that some less promising technologies will not be widely used for lack of need

Renewable Energy Sources  Direct Solar Passive solar Passive solar Active solar Active solar Photovoltaics Photovoltaics Artificial Photosynthesis Photosynthesis  Hydrogen  Indirect Solar Wind Wind Hydropower Hydropower Biomass Biomass OTEC OTEC  Tidal  Geothermal

Renewable Energy Sources  Solar Energy Primary energy source for essentially all natural ecosystems on earth Primary energy source for essentially all natural ecosystems on earth Why not the primary energy source for human societies ? Why not the primary energy source for human societies ?

Renewable Energy Sources  Solar Energy Direct Solar – directly uses electromagnetic energy of sunlight Direct Solar – directly uses electromagnetic energy of sunlight Indirect Solar – uses the stored thermal, kinetic, or chemical energy from sunlight Indirect Solar – uses the stored thermal, kinetic, or chemical energy from sunlight

 Direct Solar Solar Energy Solar Energy Passive solar Passive solar Active solar Active solar Photovoltaics Photovoltaics Artificial Photosynthesis Artificial Photosynthesis

Solar Energy Solar Energy  Passive solar Nothing moves – no pumps or working fluid Nothing moves – no pumps or working fluid Relies primarily on architectural design and construction Relies primarily on architectural design and construction

Solar Energy Solar Energy  Passive solar Archeological evidence suggest use in ancient buildings Archeological evidence suggest use in ancient buildings Primary value is in lighting and space heating and cooling of buildings Primary value is in lighting and space heating and cooling of buildings

Solar Energy Solar Energy  Passive solar Tremendous energy expenditures in lighting and space heating and cooling of buildings Tremendous energy expenditures in lighting and space heating and cooling of buildings can be reduced through passive solar designs

 Simple architectural design, such as Passive solar placement of windows placement of windows placement of overhangs placement of overhangs and can reduce energy required for heating and cooling buildings

Passive solar winter sun summer sun

Passive solar  Simple architectural design, such as Greenhouse or thermal storage by water or masonry Greenhouse or thermal storage by water or masonry

 Direct Solar Solar Energy Solar Energy Passive solar Passive solar Active solar Active solar Photovoltaics Photovoltaics Artificial Photosynthesis Artificial Photosynthesis

Solar Energy Solar Energy  Active Solar A working fluid, usually water, absorbs heat from sunlight and is moved by pumps A working fluid, usually water, absorbs heat from sunlight and is moved by pumps

Solar Energy Solar Energy  Active Solar Multiple Applications Multiple Applications  Domestic – water and space heating  Commercial & Industrial – production of steam and electricity

Domestic  Domestic Active Solar Active Solar Water is heated by sunlight in roof top solar collectors Water is heated by sunlight in roof top solar collectors

Domestic  Domestic Active Solar Active Solar Solar heated water is used in home water heater and can be used for space heating Solar heated water is used in home water heater and can be used for space heating

 Can also be used for production of Active Solar Active Solar Commercial & Industrial – production of steam and electricity Commercial & Industrial – production of steam and electricity

Active Solar Active Solar

 Direct Solar Solar Energy Solar Energy Passive solar Passive solar Active solar Active solar Photovoltaics Photovoltaics Artificial Photosynthesis Artificial Photosynthesis

Solar Energy Solar Energy  Photovoltaics aka – solar cells aka – solar cells originally developed as exotic power source for satellites originally developed as exotic power source for satellites

 Sunlight energy (photons) causes the movement of electrons (current) between layers of silicon to produce directly produce electricity from sulight Photovoltaics

now routine in calculators, outdoor lighting, and other applications now routine in calculators, outdoor lighting, and other applications tremendous increase in efficiency tremendous increase in efficiency tremendous decrease in cost tremendous decrease in cost Photovoltaics exciting developments in design and application exciting developments in design and application

 Direct Solar Solar Energy Solar Energy Passive solar Passive solar Active solar Active solar Photovoltaics Photovoltaics Artificial Photosynthesis Artificial Photosynthesis

Solar Energy Solar Energy Artificial Photosynthesis  Artificial Photosynthesis An early reaction in natural photosynthesis uses sunlight energy to split water into oxygen and hydrogen An early reaction in natural photosynthesis uses sunlight energy to split water into oxygen and hydrogen

Solar Energy Solar Energy Artificial Photosynthesis  Artificial Photosynthesis 2H 2 O + sunlight  2H 2 + O 2 research is in progress to develop an economical way to do this in vitro research is in progress to develop an economical way to do this in vitro

Solar Energy Solar Energy Artificial Photosynthesis  Artificial Photosynthesis 2H 2 O + sunlight  2H 2 + O 2 this process would produce hydrogen gas this process would produce hydrogen gas

 Often called “the fuel of the future” Hydrogen  Nearly an ideal fuel  Could be a replacement for current transportation fuels

 The primary problem is that there is almost no free hydrogen (H 2 ) on earth Hydrogen  The hydrogen is bound in molecules, such as water (H 2 O)  Free hydrogen (H 2 ) must be produced by splitting molecules

Hydrogen  Production of free hydrogen (H 2 ) by splitting molecules requires a primary energy source  Currently H 2 is produced by electrolysis of water  Electrolysis of water to produce H 2 requires substantial electricity

Hydrogen  Hydrogen energy would be more practical with direct solar production of H 2 direct solar production of H 2 fusion production of electricity fusion production of electricity solar production of electricity solar production of electricity

 Hydrogen can be used in combustion engines or in fuel cells Hydrogen  In either application, hydrogen fuel produces little-to-no pollution

Hydrogen 2 H 2 + O 2  2 H 2 O + heat energy  Burning hydrogen fuel in a combustion engine produces water as the end product

 Hydrogen can also be used in fuel cells for production of electricity  Water is again the byproduct

Hydrogen fuel cells can also run electric motors

Renewable Energy Sources  Direct Solar Passive solar Passive solar Active solar Active solar Photovoltaics Photovoltaics Artificial Photosynthesis Photosynthesis  Hydrogen  Indirect Solar Wind Wind Hydropower Hydropower Biomass Biomass OTEC OTEC  Tidal  Geothermal

Solar Energy Solar Energy Wind Wind Hydropower Hydropower Biomass Biomass OTEC OTEC  Indirect Solar

Atmospheric movement, wind, is due to differential heating of the atmosphere by the sun Atmospheric movement, wind, is due to differential heating of the atmosphere by the sun Wind Energy Wind Energy  How indirect solar ?

 Has been used for centuries Wind Energy Wind Energy  Currently a well developed technology for production of electricity

 Most of current U.S. production capacity located in California Wind Energy Wind Energy  Large new facilities under construction in Texas

Wind turbines are increasing in size and efficiency Wind Energy Wind Energy

 Potential for substantial contribution to U.S. energy needs Wind Energy Wind Energy  Many good wind energy sites located across the country

The biggest problem is the variable nature of winds  The biggest problem is the variable nature of winds Wind Energy Wind Energy no wind -- no electricity no wind -- no electricity  There are some negatives or cons with wind energy

Wind Energy Wind Energy  Problem eased by widely geographically located facilities connected to the national power grid the wind is always blowing somewhere the wind is always blowing somewhere

 Unfortunately, the rotors of wind turbines can also kill and injure birds Wind Energy Wind Energy ways to minimize impacts on birds are under study ways to minimize impacts on birds are under study

Solar Energy Solar Energy Wind Wind Hydropower Hydropower Biomass Biomass OTEC OTEC  Indirect Solar

 How indirect solar ? Hydropower Hydropower sunlight energy evaporates water, lifting it into the atmosphere sunlight energy evaporates water, lifting it into the atmosphere

Hydropower Hydropower precipitation from the atmosphere runs downhill by gravity precipitation from the atmosphere runs downhill by gravity

Energy is extracted from the water as it runs downhill Energy is extracted from the water as it runs downhill Hydropower Hydropower

 Has been used for centuries  Currently a well developed technology for production of electricity

 In the U.S., most of the good locations for big hydropower dams have been exploited Hydropower Hydropower  Around the world, many good locations for big hydropower dams have not been exploited

 Small scale hydropower could further contribute to energy needs in rural areas of less developed countries Hydropower Hydropower

 Big hydropower dams have multiple pros and cons Hydropower Hydropower  Dam opponents are calling for removal of some dams

Hydropower Hydropower  Big hydropower dams -- pros electricity generation electricity generation water reservoir water reservoir flood control flood control creates recreational area creates recreational area

Hydropower Hydropower  Big hydropower dams -- cons obstacle to fish migration obstacle to fish migration floods land floods land disrupts natural water cycle disrupts natural water cycle destroys recreational area destroys recreational area

Solar Energy Solar Energy Wind Wind Hydropower Hydropower Biomass Biomass OTEC OTEC  Indirect Solar

Biomass Energy Biomass Energy  How indirect solar ? Energy of sunlight used in photosynthesis to form complex organic compounds Energy of sunlight used in photosynthesis to form complex organic compounds

 Multiple forms Biomass Energy Biomass Energy direct combustion direct combustion waste to energy waste to energy conversion to methane conversion to methane conversion to alcohol conversion to alcohol

Biomass Energy Biomass Energy

 A concern common to all forms of biomass energy is the potential for land degradation and soil depletion Biomass Energy Biomass Energy

Solar Energy Solar Energy Wind Wind Hydropower Hydropower Biomass Biomass OTEC OTEC  Indirect Solar

O cean T hermal E nergy C onversion OTEC OTEC  What is it ?  An acronym for

OTEC OTEC  How indirect solar ? Utilizes the thermal gradient formed in bodies of water due to warming of surface water by sunlight energy Utilizes the thermal gradient formed in bodies of water due to warming of surface water by sunlight energy

 First proposed more than a century ago OTEC OTEC  Currently an experimental technology

A fluid with a low boiling point is circulated in pipes between warm surface water and cold deep water  A fluid with a low boiling point is circulated in pipes between warm surface water and cold deep water OTEC OTEC

 The fluid turns to steam at the temperature of surface water and the steam spins a turbo generator to produce electricity OTEC OTEC

 The steam recondenses to fluid as it passes into the cold temperature of deep water OTEC OTEC  The fluid is then pumped back to the surface to repeat the cycle

Has potential to benefit coastal and island areas  Has potential to benefit coastal and island areas OTEC OTEC  However, OTEC technology does not seem to be progressing and there is no clear timetable for commercial application

Renewable Energy Sources  Direct Solar Passive solar Passive solar Active solar Active solar Photovoltaics Photovoltaics Artificial Photosynthesis Photosynthesis  Hydrogen  Indirect Solar Wind Wind Hydropower Hydropower Biomass Biomass OTEC OTEC  Tidal  Geothermal

Ocean tides are due to gravitational attraction of the moon – lunar energy  Ocean tides are due to gravitational attraction of the moon – lunar energy Tidal Power Tidal Power

Water flowing in or out with the tide spins turbo generators to produce electricity Tidal Power Tidal Power

 Extremely high tides required Tidal Power Tidal Power  Relatively few good sites in the world

 Required tidal dams disrupt intertidal biological communities Tidal Power Tidal Power  Seems destined for failure

Renewable Energy Sources  Direct Solar Passive solar Passive solar Active solar Active solar Photovoltaics Photovoltaics Artificial Photosynthesis Photosynthesis  Hydrogen  Indirect Solar Wind Wind Hydropower Hydropower Biomass Biomass OTEC OTEC  Tidal  Geothermal

 Not a truly renewable energy source Geothermal Energy Geothermal Energy  Thought to have a long period of use and often classified with renewable energies

 Heat from the Earth’s interior provides the energy Geothermal Energy Geothermal Energy  Theoretically available anywhere on Earth – if go deep enough

Geothermal Energy Geothermal Energy

 Good geothermal sites are where “hot rock” is located close to the surface Geothermal Energy Geothermal Energy  Hot rock heats water to steam to spin a turbo generator to produce electricity

Geothermal Energy Geothermal Energy

 Currently a well developed technology for production of electricity  Many good geothermal sites located across the country

Geothermal Energy Geothermal Energy

Renewable Energy Sources  Direct Solar Passive solar Passive solar Active solar Active solar Photovoltaics Photovoltaics Artificial Photosynthesis Photosynthesis  Hydrogen  Indirect Solar Wind Wind Hydropower Hydropower Biomass Biomass OTEC OTEC  Tidal  Geothermal

 Renewable energies are available today !  There are enormous human and environmental “costs” associated with continued use of fossil fuels