Evaluating Energy ResourcesEvaluating Energy Resources

Renewable energy Renewable energy

Non-renewable energy Non-renewable energy

Future availability Future availability

Net energy yield Net energy yield

Cost Cost

Environmental effects Environmental effects

Extracting Energy and Mineral ResourcesExtracting Energy and Mineral Resources

Surface, subsurface mines, wellsSurface, subsurface mines, wells

Removing Nonrenewable Mineral ResourcesRemoving Nonrenewable Mineral Resources

Surface miningSurface mining Subsurface miningSubsurface mining

Overburden Overburden

Points of ViewPoints of View

Cornucopians - we will not run out ofnon-renewable resources because ofeconomics and technology

Cornucopians - we will not run out ofnon-renewable resources because ofeconomics and technology

Neo-Malthusians - we will run out ofnon-renewable resources (limitedsupply)- must control population, conserve

Neo-Malthusians - we will run out ofnon-renewable resources (limitedsupply)- must control population, conserve

Supplemental EnergySupplemental Energy

Solar energy - 99% of all energy used

Supplemental energy - everything else

History of Supplemental Energyin United StatesHistory of Supplemental Energyin United States

Wood through mid-1800s-Renewable-Maximum sustained yield limits supply

Wood through mid-1800s-Renewable-Maximum sustained yield limits supply

Coal replaced wood by 1900Coal replaced wood by 1900Oil, natural gas exploited (since mid-1900s)

#1-oil, #2-natural gas, #3-coal- all non-renewable

Oil, natural gas exploited (since mid-1900s)

#1-oil, #2-natural gas, #3-coal- all non-renewable

Use growing dramaticallyUse growing dramatically

Year

210020251950187518000

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60

80

100

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Wood

Coal

Oil

Nuclear

HydrogenSolar

Natural gas

How long will supplies last?How long will supplies last?

U.S. (5%) uses 25% of energyU.S. (5%) uses 25% of energyDepends on:

- rate of use- discovery of new supplies

Depends on:- rate of use- discovery of new supplies

Resource supply lifetime- oil - 30-60 years- natural gas - 50-200 years- coal - 65-900 years

Resource supply lifetime- oil - 30-60 years- natural gas - 50-200 years- coal - 65-900 years

North American Energy ResourcesNorth American Energy Resources

Oil ResourcesOil Resources

Petroleum (crude oil)Petroleum (crude oil)Primary recovery - 1/3 recoverablePrimary recovery - 1/3 recoverableSecondary recovery - heavy oil (10%)Secondary recovery - heavy oil (10%)

U.S. is major oil importer- thousands of low-output wells

U.S. is major oil importer- thousands of low-output wellsSaudi Arabia - largest known reserves

- supply world for 10 years- Alaskan supply - 6 months

Saudi Arabia - largest known reserves- supply world for 10 years- Alaskan supply - 6 months

OPECOPEC

Organization of Petroleum ExportingCountries

Organization of Petroleum ExportingCountries

Supplies ~30% of U.S. oil importsSupplies ~30% of U.S. oil imports

#1 Mexico#2 Canada#3 Venezuela (OPEC member)

#1 Mexico#2 Canada#3 Venezuela (OPEC member)

Oil Shale and Tar SandsOil Shale and Tar Sands

Oil shale3X conventional

Oil shale3X conventional

Kerogen25 gallons/ton

Energy in=energy out

Kerogen25 gallons/ton

Energy in=energy out Tar sands Tar sands

Bitumen3X return on energy inputs

Bitumen3X return on energy inputs

Natural GasNatural Gas

50-90% methane 50-90% methane

Propane, butaneremoved, liquified

Propane, butaneremoved, liquified

Cleanest burning,lowest costs

Cleanest burning,lowest costs

Problems: leaks,explosions

Problems: leaks,explosions

Unconventional: tight sands- 1-3 X conventional supply, but expensive

Unconventional: tight sands- 1-3 X conventional supply, but expensive

CoalCoal

Carbon (energy content) and sulfur

CoalCoal

Bituminous most abundant (52%), buthigh in sulfur

Bituminous most abundant (52%), buthigh in sulfur

Anthracite most ideal (high energy, lowsulfur), but least abundant (2%)

Anthracite most ideal (high energy, lowsulfur), but least abundant (2%)

Subbituminous (38%) moderate energy,moderate pollution potential

Lignite (8%) low energy, low pollutionpotential

Subbituminous (38%) moderate energy,moderate pollution potential

Lignite (8%) low energy, low pollutionpotential

CoalCoal

Surface versus subsurface mines Surface versus subsurface mines

North American Energy ResourcesNorth American Energy Resources

Coal Mining in United StatesCoal Mining in United States

Western surface mines Western surface mines

Mostly subbituminous, lignite Mostly subbituminous, lignite

Used mostly for generating electricity,steel-making industry

Used mostly for generating electricity,steel-making industry

Most used east of Mississippi River Most used east of Mississippi River

Transportation vs. volume costs, sulfur- slurry pipeline?

Transportation vs. volume costs, sulfur- slurry pipeline?

Burning Coal More CleanlyBurning Coal More Cleanly

Fluidized-Bed Combustion

Fluidized-Bed Combustion

-calcium-calciumsulfate usedsulfate usedin dry wallin dry wall

Coal Gasification - methaneCoal Gasification - methane

Raw coal

Pulverizer

Air oroxygen

Steam

Pulverized coalSlag removal

Recycle unreactedcarbon (char)

Raw gasesCleanmethane gas

Recoversulfur

Methane(natural gas)

2CCoal

+ O2 2CO

CO + 3H2 CH4 + H2O

Remove dust,tar, water, sulfur

Coal Liquefaction - liquid fuelsCoal Liquefaction - liquid fuels

Both gasification and liquefaction lose30-40% of energy contained in coal

Both gasification and liquefaction lose30-40% of energy contained in coal

Nuclear EnergyNuclear Energy

Big question mark in energy industryBig question mark in energy industryTremendous potential, plagued by

safety and cost problems

Tremendous potential, plagued bysafety and cost problems

3 ways to produce nuclear power1) conventional nuclear fission reactor2) breeder nuclear fission reactor3) nuclear fusion reactor

3 ways to produce nuclear power1) conventional nuclear fission reactor2) breeder nuclear fission reactor3) nuclear fusion reactor

Nuclear EnergyNuclear Energy

Use radioactive isotopesUse radioactive isotopesIsotopes - different forms of same

element- atoms have differing masses- e.g. U-238, U-235

Isotopes - different forms of sameelement- atoms have differing masses- e.g. U-238, U-235

Radioactive - unstable atoms emitradiation (rays and particles)

Radioactive - unstable atoms emitradiation (rays and particles)

Nuclear EnergyNuclear Energy

Conventional fission reactors

Conventional fission reactors

Uranium-235(U-238 common)

Uranium-235(U-238 common)

Nucleus split by moving neutron

Nucleus split by moving neutron

- Core, heat exchanger, generator

Reactors in the United StatesReactors in the United States

Nuclear EnergyNuclear Energy

Breeder fission reactorsBreeder fission reactorsUses plutonium-239 as fuel

U-238 + neutron = Pu-239

Uses plutonium-239 as fuelU-238 + neutron = Pu-239

Pu-239 fissioned, but more producedfrom U-238- produces more Pu-239 than it uses

Pu-239 fissioned, but more producedfrom U-238- produces more Pu-239 than it uses

Nuclear EnergyNuclear Energy

Nuclear fusion reactorsNuclear fusion reactorsCombine atoms of hydrogen isotopes

- deuterium, tritium

Combine atoms of hydrogen isotopes- deuterium, tritium

Requires high temperature- 100 million °C- experimental- uncontrolled fusion - hydrogen bomb

Requires high temperature- 100 million °C- experimental- uncontrolled fusion - hydrogen bomb

Problems with Nuclear PowerProblems with Nuclear Power

Safety Safety Disposal of radioactive wastesDisposal of radioactive wastesUse of fuel for weaponsUse of fuel for weaponsReduced growth in demand for

electricity

Reduced growth in demand for electricity

High construction, operating costsHigh construction, operating costs

Funding Funding

Safety ConcernsSafety Concerns

Radiation concerns Radiation concerns Susceptible tissues: reproductive

organs, bone marrow, digestive tract, spleen, lymph glands, fetuses

Susceptible tissues: reproductive organs, bone marrow, digestive tract, spleen, lymph glands, fetuses

Rem - unit of radiation exposure- 10 rems: low level, few effects- 100 rems: sterility, no short-term deaths- 1000 rems: death in days

Rem - unit of radiation exposure- 10 rems: low level, few effects- 100 rems: sterility, no short-term deaths- 1000 rems: death in days

Annual Radiation ExposureAnnual Radiation Exposure

Average 230 mrem (0.230 rem)Average 230 mrem (0.230 rem)

130 mrem from natural sources100 mrem from human activities

- 0.1 mrem from nuclear reactors

130 mrem from natural sources100 mrem from human activities

- 0.1 mrem from nuclear reactors

Lifespan reduced by 1 minuteLifespan reduced by 1 minute

Big FearsBig Fears

Core meltdown- Chernobyl ‘86

Core meltdown- Chernobyl ‘86

Containment shell ruptureContainment shell rupture

Both have potential for releasing huge amounts of radiation

Both have potential for releasing huge amounts of radiation

Disposal of Radioactive WastesDisposal of Radioactive Wastes

Nuclear fuel cycle

Disposal of Radioactive WastesDisposal of Radioactive Wastes

No long-term storage facility- protected for 10,000 years- radiation declines to low levels

No long-term storage facility- protected for 10,000 years- radiation declines to low levels

Most wastes stored on-siteMost wastes stored on-site

Site under development- Yucca Mountain in Nevada

Site under development- Yucca Mountain in Nevada

Yucca MountainYucca Mountain

Temporary StorageTemporary Storage