Energy and Waste Chapters 15, 16, and 22 Living in the

Nonrenewable Energy
Advanced Placement Environmental Science
Special Credits to Dr. Mark Ewoldsen, La Canada High School
1. Energy Resources
2. Oil
3. Natural Gas
4. Coal
5. Nuclear Energy
Energy Sources
Modern society requires large quantities of energy
that are generated from the earth’s natural
Primary Energy Resources: The fossil fuels(oil, gas,
and coal), nuclear energy, falling water, geothermal, and
solar energy.
Secondary Energy Resources: Those sources which
are derived from primary resources such as electricity,
fuels from coal, (synthetic natural gas and synthetic
gasoline), as well as alcohol fuels.
The laws of thermodynamics tell us two
things about converting heat energy from
steam to work:
1) The conversion of heat to work cannot be 100
% efficient because a portion of the heat is
2) The efficiency of converting heat to work
increases as the heat temperature increases.
Energy Units and Use
Btu (British thermal unit) - amount of energy
required to raise the temperature of 1 lb of
water by 1 ºF.
cal (calorie) - the amount of energy required to
raise the temperature of 1 g of water by 1 ºC.
Commonly, kilocalorie (kcal) is used.
1 Btu = 252 cal = 0.252 kcal
1 Btu = 1055 J (joule) = 1.055 kJ
1 cal = 4.184 J
Energy Units and Use
Two other units that are often seen are the horsepower
and the watt. These are not units of energy, but are
units of power.
1 watt (W) = 3.412 Btu / hour
1 horsepower (hp) = 746 W
Watt-hour - Another unit of energy used only to describe
electrical energy. Usually we use kilowatt-hour (kW-h)
since it is larger.
quad (Q) - used for describing very large quantities of
energy. 1 Q = 1015 Btu
Evaluating Energy Resources
U.S. has 4.6% of world population; uses
24% of the world’s energy;
84% from nonrenewable fossil fuels (oil, coal,
& natural gas);
7% from nuclear power;
9% from renewable sources (hydropower,
geothermal, solar, biomass).
Changes in U.S. Energy Use
Energy resources removed from the
earth’s crust include: oil, natural gas,
coal, and uranium
Fossil Fuels
Fossil fuels originated from the decay of living
organisms millions of years ago, and account for
about 80% of the energy generated in the U.S.
The fossil fuels used in energy generation are:
Natural gas, which is 70 - 80% methane (CH4)
Liquid hydrocarbons obtained from the distillation of
Coal - a solid mixture of large molecules with a H/C
ratio of about 1
Problems with Fossil Fuels
Fossil fuels are nonrenewable resources
At projected consumption rates, natural gas and
petroleum will be depleted before the end of
the 21st century
Impurities in fossil fuels are a major source
of pollution
Burning fossil fuels produce large amounts
of CO2, which contributes to global
1. Energy Resources
2. Oil
3. Natural Gas
4. Coal
5. Nuclear Energy
Deposits of crude oil often are trapped within the
earth's crust and can be extracted by drilling a
Fossil fuel, produced by the decomposition of
deeply buried organic matter from plants &
Crude oil: complex liquid mixture of
hydrocarbons, with small amounts of S, O, N
How Oil Drilling Works by Craig C. Freudenrich, Ph.D.
Sources of Oil
•Organization of Petroleum Exporting Countries
(OPEC) -- 13 countries have 67% world
• Algeria, Ecuador, Gabon, Indonesia, Iran,
Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi
Arabia, United Arab Emirates, & Venezuela
•Other important producers:
Alaska, Siberia, & Mexico.
Oil in U.S.
•2.3% of world
•uses nearly 30%
of world
•65% for
dependence on
Low oil prices have stimulated economic growth, they
have discouraged / prevented improvements in energy
efficiency and alternative technologies favoring
renewable resources.
• Burning any fossil fuel releases carbon dioxide into the
atmosphere and thus promotes global warming.
• Comparison of CO2 emitted by fossil fuels and nuclear
Crude oil is transported to a refinery
where distillation produces
How Oil Refining Works
by Craig C.
Freudenrich, Ph.D.
1. Energy Resources
2. Oil
3. Natural Gas
4. Coal
5. Nuclear Energy
Natural Gas - Fossil Fuel
• Mixture
•50–90% Methane (CH4)
•Ethane (C2H6)
•Propane (C3H8)
•Butane (C4H10)
•Hydrogen sulfide (H2S)
Sources of Natural Gas
•Russia & Kazakhstan - almost 40% of
world's supply.
•Iran (15%), Qatar (5%), Saudi Arabia
(4%), Algeria (4%), United States (3%),
Nigeria (3%), Venezuela (3%);
•90–95% of natural gas in U.S. domestic
(~411,000 km = 255,000 miles of
billion cubic metres
Natural Gas
Experts predict increased use of natural gas
during this century
Natural Gas
When a natural gas field is tapped, propane and
butane are liquefied and removed as liquefied
petroleum gas (LPG)
The rest of the gas (mostly methane) is dried,
cleaned, and pumped into pressurized pipelines for
Liquefied natural gas (LNG) can be shipped in
refrigerated tanker ships
1. Energy Resources
2. Oil
3. Natural Gas
4. Coal
5. Nuclear Energy
Coal: Supply and Demand
Coal exists in many forms therefore a
chemical formula cannot be written for it.
Coalification: After plants died they
underwent chemical decay to form a product
known as peat
Over many years, thick peat layers formed.
Peat is converted to coal by geological events
such as land subsidence which subject the peat
to great pressures and temperatures.
Ranks of Coal
Lignite: A brownish-black coal of low quality (i.e.,
low heat content per unit) with high inherent
moisture and volatile matter. Energy content is
lower 4000 BTU/lb.
Subbituminous: Black lignite, is dull black and
generally contains 20 to 30 percent moisture
Energy content is 8,300 BTU/lb.
Bituminous: most common coal is dense and black
(often with well-defined bands of bright and dull
material). Its moisture content usually is less than
20 percent. Energy content about 10,500 Btu / lb.
Anthracite :A hard, black lustrous coal, often
referred to as hard coal, containing a high
percentage of fixed carbon and a low percentage of
volatile matter. Energy content of about 14,000
Btu/lb. Powerpoint%5CCoal.ppt
Main Coal Deposits-US
Advantages and Disadvantages
•Most abundant fossil fuel
•Major U.S. reserves
•300 yrs. at current consumption rates
•High net energy yield
•Dirtiest fuel, highest carbon dioxide
•Major environmental degradation
•Major threat to health
© Brooks/Cole Publishing Company / ITP
Coal gasification  Synthetic
natural gas (SNG)
Coal liquefaction  Liquid fuels
High environmental impact (Nox &
Sulfur in Coal
When coal is burned, sulfur is released
primarily as sulfur dioxide (SO2 - serious
Coal Cleaning - Methods of removing sulfur
from coal include cleaning, solvent refining,
gasification, and liquefaction Scrubbers are
used to trap SO2 when coal is burned
Two chief forms of sulfur is inorganic (FeS2
or CaSO4) and organic (Sulfur bound to C)
Acid Mine
The impact of mine
drainage on a
lake after
receiving effluent
from an
impoundment for
over 50 years
Relatively fresh tailings in an
The same tailings impoundment
after 7 years of sulfide
oxidation. The white spots in
Figures A and B are gulls.
Mine effluent
discharging from
the bottom of a
waste rock pile
Shoreline of a
pond receiving
AMD showing
accumulation of
iron hydroxides
on the pond
Groundwater flow through a tailings
impoundment and discharging into
lakes or streams.
1. Energy Resources
2. Oil
3. Natural Gas
4. Coal
5. Nuclear Energy
Nuclear Energy
In a conventional nuclear power
a controlled nuclear fission chain
heats water
produce high-pressure steam
that turns turbines
generates electricity.
Nuclear Energy
Controlled Fission
Chain Reaction
neutrons split the
nuclei of atoms such
as of Uranium or
release energy (heat)
Controlled Nuclear Fission Reaction Energy%20Use%20-%203.ppt
• Radioactive decay continues until the the original
isotope is changed into a stable isotope that is not
• Radioactivity: Nuclear changes in which unstable
(radioactive) isotopes emit particles & energy
• Types
• Alpha particles consist of 2 protons and 2 neutrons,
and therefore are positively charged
• Beta particles are negatively charged (electrons)
• Gamma rays have no mass or charge, but are a form
of electromagnetic radiation (similar to X-rays)
• Sources of natural radiation
Cosmic rays
Sources Energy%20Use%20-%203.ppt
The time needed for one-half of the nuclei in a
radioisotope to decay and emit their radiation to
form a different isotope
Uranium 235
Plutonium 239
710 million yrs
24.000 yrs
alpha, gamma
alpha, gamma
During operation, nuclear power plants
produce radioactive wastes, including some
that remain dangerous for tens of thousands
Diagram of Radioactive Decay Energy%20Use%20-%203.ppt
Effects of Radiation
• Genetic damages: from mutations
that alter genes
• Genetic defects can become
apparent in the next generation
• Somatic damages: to tissue, such as
burns, miscarriages & cancers EVR3019/Nuclear_Waste.ppt
Radioactive Waste
1. Low-level radiation (Gives of low amount of
• Sources: nuclear power plants, hospitals &
• 1940 – 1970 most was dumped into the ocean
• Today deposit into landfills
2. High-level radiation (Gives of large amount of
• Fuel rods from nuclear power plants
• Half-time of Plutonium 239 is 24000 years
• No agreement about a safe method of storage
Radioactive Waste
1. Bury it deep underground.
• Problems: i.e. earthquake, groundwater…
2. Shoot it into space or into the sun.
• Problems: costs, accident would affect large area.
3. Bury it under the Antarctic ice sheet.
• Problems: long-term stability of ice is not known,
global warming
4. Most likely plan for the US
• Bury it into Yucca Mountain in desert of Nevada
• Cost of over $ 50 billion
• 160 miles from Las Vegas
• Transportation across the country via train & truck
Yucca Mountain EVR3019/Nuclear_Waste.ppt
Plutonium Breeding
is the most plentiful isotope of
Non-fissionable - useless as fuel
Reactors can be designed to convert
238U into a fissionable isotope of
plutonium, 239Pu EVR3019/Nuclear_Waste.ppt
Conversion of 238U to 239Pu
conditions, the
neutrons given
off by fission
reactions can
"breed" more
fuel, from
otherwise nonfissionable
isotopes, than
they consume EVR3019/Nuclear_Waste.ppt
Reprocess Nuclear Fuel
During the operation of a nuclear
reactor the uranium runs out
Accumulating fission products
hinder the proper function of a
nuclear reactor
Fuel needs to be (partly) renewed
every year EVR3019/Nuclear_Waste.ppt
Plutonium in Spent Fuel
Spent nuclear fuel contains many
newly formed plutonium atoms
Miss out on the opportunity to split
Plutonium in nuclear waste can be
separated from fission products and
Cleaned Plutonium can be used in a
different Nuclear Reactor EVR3019/Nuclear_Waste.ppt
Nuclear Energy
Concerns about the safety, cost,
and liability have slowed the
growth of the nuclear power
Accidents at Chernobyl and
Three Mile Island showed that a
partial or complete meltdown is
Nuclear Power Plants in U.S. Energy%20Use%20-%203.ppt
Three Mile Island
• March 29, 1979, a reactor near Harrisburg, PA lost
coolant water because of mechanical and human
errors and suffered a partial meltdown
• 50,000 people evacuated & another 50,000 fled area
• Unknown amounts of radioactive materials released
• Partial cleanup & damages cost $1.2 billion
• Released radiation increased cancer rates.
• April 26, 1986, reactor explosion (Ukraine) flung
radioactive debris into atmosphere
• Health ministry reported 3,576 deaths
• Green Peace estimates32,000 deaths;
• About 400,000 people were forced to leave their
• ~160,000 sq km (62,00 sq mi) contaminated
• > Half million people exposed to dangerous levels of
• Cost of incident > $358 billion
Nuclear Energy
Nuclear plants must be decommissioned after
15-40 years
New reactor designs are still proposed
Experimental breeder nuclear fission reactors
have proven too costly to build and operate
Attempts to produce electricity by nuclear
fusion have been unsuccessful
Use of Nuclear Energy
• U.S. phasing out
• Some countries (France, Japan) investing
• U.S. currently ~7% of energy nuclear
• No new U.S. power plants ordered since 1978
• 40% of 105 commercial nuclear power expected
to be retired by 2015 and all by 2030
• North Korea is getting new plants from the US
• France 78% energy nuclear
Phasing Out Nuclear Power
•Multi-billion-$$ construction costs
•High operation costs
•Frequent malfunctions
•False assurances and cover–ups
•Overproduction of energy in some areas
•Poor management
•Lack of public acceptance
Energy &
Mineral resources
2) Energy