ENERGY

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Chapter 19
Conventional Energy
Ally Dykes
Allison Smith
CASE STUDY
• Coal Bed Methane
• Conventional energy (obama)
WHAT the Duck is energy and
Where the gazelle do we get it?!
• The energy we use comes from potential energy in our food whose energy
is measured in calories.
– Energy Use is Changing:
• Fire was the first human energy technology
• Charcoal from fire
• Muscle power from domestic animals
• Wind and water power
• The steam engine and wood
• COAL
• Oil & Fossil Fuels on which we are now dependent
– Costing us socially, economically, and environmentally.
3N3RGY US3
• Increase in energy use is expected mainly due
to developing countries
• Competition for limited oil supplies plays a
large role in geopolitics.
• Demand will outweigh supply and prices will
continue to rise
• The average person in the U.S. or Canada uses
more than 60 barrels of oil per year.
How Energy is used:
U.S. Energy consumption
U.S. Oil Suppliers
Energy Use
Dats sooooo COAL!
• Coal: fossilized plant material preserved by burial in sediments and altered
by geological forces that compact and condense it into a carbon-rich fuel.
• Takes so long to form that it is considered a non-renewable resource
• Coal Resources are Vast (almost 10 trillion metric tons!):
• 90 percent of coal deposits are located in North America, Europe, and
Asia.
• China and India plan to increase coal consumption to raise standards of
living while exacerbating global warming.
Coal Mining is DIRT Nasty yall
• Coal Mining is a dirty, dangerous business:
• Underground mines are subject to cave-ins, fires, accidents,
and poisonous/explosive gases.
• Many disabled by black lung disease.
• Strip mining or surface mining is cheaper than underground
mining but makes the land unfit for any other use.
• Contribute to water pollution through run off.
• Mountaintop removal is a type of strip mining where the tops
of mountain ridges are scraped off and dumped into valleys
below coal seams.
Burn baby burrrn pollutant
inferno!
• Burning coal releases many pollutants:
• Releases radioactivity and toxic metals poisoning the
environment and humans
• uranium, arsenic, lead, cadmium, mercury, rubidium,
thallium, and zinc are absorbed by plants
• 900 million tons of coal are burned every year in the U.S.
• Coal burning is the largest single source of acid rain in many
areas
• Effects= human health costs, injury to plants and animals, and
damage to buildings and property.
I loveee me some petroleum!
• Oil: petroleum is derived from organic molecules created by living
organisms millions of years ago and buried in sediments with high
pressures and temperatures that formed them into energy-rich
compounds.
• An oil pool is individual droplets or a thin layer of liquid permeating spaces
in a porous sandstone or limestone.
Someone grab me a glass o’
petroleum
• Energy companies claim directional drilling
would effect less land.
• Methods for squeezing more oil from a
resevoir are called secondary recovery
techniques.
Oil resources have some A.D.D.
•
•
•
•
Oil resources are only concentrated in few places.
Total amount = 4 trillion barrels
Largest Supply of proven-in-place oil is in Saudi Arabia
Believed that resevoirs are around and under the capsain sea and may
hold 200 billion barrels.
• Importing oil leads to environmental damage
– 1.5 Million barrels of oil spill per year
Largest untapped oil field in the U.S. thought to be in Arctic National
Wildlife refuge
Oil Shales and Tar Sands have
sooooooooooooooooo much petroleum
• Esitmates of total oil supply excludes shale oil and tar sands
• Liquid petroleum can be extracted from sands with hot water, chemicals,
or other stripping processes.
– Environmental Effects
• Typical plant creates 15 mil cubic meters of toxic sludge and
consumes/ contaminates billion of liters of water per year.
• Oil shales are located in western U.S.
• Heated, liquified and extracted from stone
• Could yield several trillion barrels of oil
– Expensive, uses vast quantities of water, potential for air and water
pollution, produces large amounts of waste
Natural GAS! …awkward
• World’s largest commercial fuel after oil and coal.
• Mostly methane, propane, and hydrocarbons
• Most rapid growing energy source
– Convienent, cheap, clean
– Less CO2 Emmissions
– Help reduce global warming
• Shipped easily and economically through buried pipelines
• Gas is liquified and transported
• Difficult to ship and store gas between continents
– Finding sites to unload ships is difficult due to possibility of explosion
– Can ruin coastal ecology
Most of the World’s Known
Natural Gas is in a Few Countries
• Middle East = 2/3 of all proven natural gas reserves
• Former Soviet Union = 31% of known natural gas
reserves (mostly in Siberia and the Central Asian
republics) + 40% of all production.
• The total ultimately recoverable natural gas resources are
estimated to be 10,000 trillion feet3.
• Current gas reserves represent roughly a 60-year supply
at present usage rates.
• Proven reserves in North America are 4.6% of the world
total (10 year supply).
Most of the World’s Known Natural
Gas is in a Few Countries, Continued.
• In 2005, George Bush ordered the Bureau of Land
Management to expedite oil and gas leasing in the name of
national security.
• Proponents of increased drilling claim that too much land is
“off-limits” for energy production.
• Only 12% of federal gas and oil resources are under
protected areas.
• The Interior Department has removed protection from de
facto wilderness areas.
• Some communities in western states are passing ordinances
that restrict the density of wells and the dumping of drilling
wastes.
There May be Vast Unconventional
Gas Sources
• There may be extensive unconventional sources of gas in
unexpected places. Example: hydrate deposits in arctic
permafrost and beneath deep ocean sediments.
• 50 oceanic deposits + 12 land deposits
• 10,000 gigatons (1013 tons) of carbon
• Difficult to extract, store, and ship.
• Melting of these deposits = a catastrophic spiral of global
warming
• Japan plans exploratory extraction in the next few years
• Methane can also be produced by digesting garbage or manure
• Some U.S cities collect methane from landfills and sewage
sludge digestion
Nuclear Power
• Eisenhower’s “atoms for peace” speech.
• American utilities ordered 140 new reactors for
power plants.
• Predictions of 1,500 reactors in the US alone.
• In 1970, IAEA predicted a worldwide nuclear power
generation of at least 4.5 million megawatts by the
year 2000.
Nuclear Energy, Continued
• Rapidly increasing construction costs, declining
demand for electric power, and safety fears have
made nuclear energy much less attractive.
• Wind energy, solar energy, hydropower
• After 1973 only 13 orders were placedeventually cancelled
• Expensive wild goose chase.
How Do Nuclear Reactors
Work?
• U235, a natural occurring radioactive isotope of
uranium.
• Mining and processing uranium to create nuclear
fuel is even more dirty and dangerous than coal
mining.
• Uranium mine workers have died from lung cancer
caused by high radon and dust levels.
• Mountains of radioactive tailings and debris have
been left around fuel preparation plants.
How Do Nuclear Reactors Work 2
• U235 concentration reaches about 3% >
the uranium is formed into cylindrical
• Each 8.5 g pellet is equivalent to a ton
of coal or four barrels of crude oil.
• The pellets are stacked in hollow metal
rods approximately four meters long.
• About 100 of these rods are bundled
together to make a fuel assembly.
• Thousands of fuel assemblies are
bundled together in the reactor core.
• Radioactive uranium atoms are
unstable
How Do Nuclear Reactors Work 3
• The neutrons released by one
atom will trigger the fission of
another uranium etc.
• Thus a self-sustaining chain
reaction is set in motion
• The chain reaction is
moderated (slowed) in a
power plant by a neuronabsorbing cooling solution
that circulates between the
fuel roads.
How Do Nuclear Reactors Work 4
• Control rods of neuron-absorbing
material are inserted into spaces
between fuel assemblies to shut down
the fission reaction
• A coolant is circulated between the fuel
rods to remove excess heat.
• The greatest danger = a cooling system
failure > meltdown
There are Many Different Reactor
Designs
• 70% of the nuclear plants in the US and in the world
are pressurized water reactors (PWR).
• A typical nuclear power plant has 40,000 valves.
• Under normal operating conditions, a PWR releases
very little radioactivity
and is probably less
dangerous for nearby
residents than a
coal-fired power plant.
There are Many Different Reactor
Designs 2
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•
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Boiler Water Reactor
Canadian Deuterium Reactor
MAGNOX Design
RBMK
Issues with
These Designs
Windscale Plutonium Reactor in England
Chernobyl in Ukraine
David-Besse plant
First Energy has been cited for numerous
maintenance errors, health and safety problems,
and pollution violations.
• 9/11 has people scared.
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•
•
Some Alternate Reactor
Designs May Be Safer
• Gas-Cooled Reactor (HTGCR) sometimes called a
“pebble-bed reactor”
• If the reactor core is kept small, it cannot generate
enough heat to melt the ceramic coating
• Fuel pellets are loaded into the reactor from the top,
shuffle through the core as the uranium is consumed,
and emerge from the bottom as spent fuel.
• Since the reactors are small, they can be added to a
system a few at a time, avoiding the costs, construction
time, and along-range commitment of large reactors.
Some Alternate Reactor
Designs May Be Safer,
Continued
• The Process-Inherent Ultimate Safety (PIUS) reactor
design
• If the primary coolant pressure is lost, however, the
surrounding water floods the core, and the boron
poisons the fission reaction.
• The Canadian “slow-poke” is a small-scale version of the
PIUS design
• Promoters claim that a runaway reaction is impossible in
this design and that it makes an attractive and costefficient alternative to fossil fuels.
• Neither of these alternative reactor designs eliminates
other problems, such as waste disposal.
SOME LAWLS
DR UNFRIED COVER YOUR EYES THIS ONE IS
INAPPROPRIATE!!!
The wind mill goes up to the solar panel and says “it must suck
to sit in the hot sun all day” and the solar panel replies ”its
better than having my work be one long blow job".
Breeder Reactors Could Extend
the Life of our Nuclear Fuel
• High-density, high-pressure, breeder
reactors that produce fuel rather than
consume it.
• Create fissionable plutonium and
thorium isotopes
• The starting material is plutonium
• After about ten years of operation, a
breeder reactor would produce enough
plutonium to start another reactor.
• Sufficient uranium currently is
stockpiled in the US to produce
electricity for 100 years
Breeder Reactors Could Extend
the Life of our Nuclear Fuel,
Continued
• Concern about safety
• They produce excess plutonium that can be used for
bomb
• Fear of this material falling into a terrorist’s hands .
• Japan’s Moju breeder
• In 1986, France put into operational full-sized
commercial breeder reactor, the SuperPhenix, near
Lyons. It cost three times the original estimate to build
and produces electricity at twice the cost per kilowatt of
conventional nuclear power.
Radioactive Waste
Management
• Until 1970, the US, Britain, France, and Japan disposed of
radioactive wastes in the ocean.
• The former Soviet Union dumped 2.5 million curies of
radioactive waste into the oceans, more than twice as much
as the combined amounts that 12 other nuclear nations have
reported dumping over the past 45 years.
• Enormous piles of mine wastes and abandoned mill tailings
• 1,000 tons of uranium = 100,000 tons of tailings and 3.5
million liters of liquid waste.
• There are now approximately 200 million tons of radioactive
waste in piles around mines and processing plants in the US.
Radioactive Waste
Management 2
• There are about 100.000 tons of low-level waste and about 15,000
tons of high level wastes in the US
• High level waste consists mainly of spent fuel rods from commercial
nuclear power plants and assorted wastes from nuclear weapons
production
• Stored in deep water-filled pools at the power plants.
• Large metal dry casks placed outside power plants.
• Fierce opposition from local residents
• Most nuclear power plants are built near rivers, lakes, or seacoastsfear of spreading
• Example: Wisconsin’s Point Beach nuclear plant
• High-level repository near Yucca Mountain, Nevada.
• Spent = $1 billion + more costs = $10 billion to $35 billion.
Radioactive Waste
Management 3
• Russia has offered to store nuclear waste from other
countries.
• They expect that storing 20,000 tons of nuclear waste should
pay about $20 billion.
• Monitored retrievable storage
• Safeguarding wastes would be expensive
• Sites = susceptible to wars or terrorist attacks.
• Shipping nuclear waste to a storage site worries many
people.
• The Energy Department has performed crash tests on the
shipping containers and assures us they are safe.
Decommissioning Old Nuclear
Plants is Expensive
• Most plants are designed for a life of 30 yeas.
• Power plants must be taken apart and the
most radioactive pieces have to be stores just
like other waste.
• These pieces have to be cut apart by remotecontrol robots because they are too
dangerous to be worked on directly.
• It generally costs two to then times more to
tear them down as to build them in the first
place.
• Altogether, the 103 reactors now in operation
might cost somewhere between $200 billion
and $1 trillion to decommission.
Changing Fortunes of Nuclear
Power
• Antinuclear groups
• Workers, consumers, utility officials, and others who stand to benefit from
this new technology rally in support of nuclear power.
• About half of all Americans support atomic energy, and about ¼ say they
wouldn’t mind having a nuclear plant within 10 miles of their home.
• The 103 nuclear reactors now operating in 21 states produce about 20% of
all electricity consumed in the US.
• Advocates are promoting nuclear reactors as clean and environmentally
friendly because they don’t emit greenhouse gases.
• Critics point out that huge amounts of fossil fuels are used to mine, process,
and ship fuels as well as to dismantle reactors and store wastes.
Nuclear Fusion
• Alternative to nuclear fission that could have virtually limitless
potential
• Deuterium and tritium
• If temperatures = 100 million degrees Celsius and pressures
= several bullion atmosphere > fusion of deuterium and
tritium
• Magnetic Confinement
• Inertial Confinement
• (+) = production of fewer radioactive wastes, the elimination
of fissionable products that could be made into bombs, and a
fuel supply that is much larger and less hazardous than
uranium.
• (-) = another expensive wild-goose chase and that will never
generate enough energy to pay back the fortune spent on its
U.S Energy Policy
• Vice President Dick Cheney said
that oil, coal and natural gas would
remain the US’s primary energy
source for “years down the road”.
• Cheney offered a supply-oriented
energy philosophy.
• He also strongly supported the
use of nuclear power.
• The committee consisted entirely
of executives and lobbyists from
the energy industry.
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