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Chapter 17
Nonrenewable Energy
Section 1: Energy Resources and Fossil
Fuels
• Fuels are used for 5 main purposes:
1. Transportation (# 1 use of crude oil)
2. Electricity (coal & nuclear power)
3. Heating and Cooling
(oil, natural gas, electricity)
4. Cooking (natural gas or electricity)
5. Manufacturing (coal)
The sustainability of a fuel for a
particular use depends on:
•
•
•
•
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The energy content of the fuel
Cost
Availability
Safety
By-products of using the fuel (waste)
*Most of the energy we use comes from fossil
fuels
Fossil Fuels:
• The remains of ancient organisms that have
turned into coal, crude oil, and natural gas
Two main problems with using fossil fuels:
• Supply is very limited
• Obtaining them and using them causes
environmental problems (pollution)
Electricity
The energy from fossil fuels (coal) is often
converted into electric energy
Two disadvantages:
1. It is difficult to store
2. Other energy sources must be
used to generate electricity
How A Coal Burning Power Plant
Works (fig. 3 page 468)
How a coal-fired power plant works
1. Burning fossil fuels release energy in the
form of heat, which is used to boil water and
produce high-pressure steam
2. Steam is directed against blades of a turbine,
which is set in motion
3. Turbine is connected to electric generator,
which is set in motion, generating electricity
4. Steam from turbine is directed to condenser
where it cools and becomes liquid water to
be cycled again
Energy Use
• People in developed countries use more
energy than people in developing countries
Energy Use in the U.S.
• Industrial Use
38%
• Transportation
27%
• Commercial
16%
• Residential
19%
Coal
• Coal forms from the remains of plants that
lived in swamps hundreds of millions of years
ago
– Layers of sediment compress the remains
– Heat & pressure within the Earth’s crust cause the
coal to form
• Coal is the world’s most abundant fossil fuel,
also the dirtiest
• More than ½ of the electricity in the U.S. is
generated by coal
Coal Mining – Two Types
1. Surface Mining:
a. Layers of rock & soil are removed to get coal that
is near the surface
b. This method is VERY destructive to the
environment
2. Sub-Surface Mining:
a.These are mines that are dug deep (50 meters or
more) into Earth’s surface
b.This type of mining is better for the environment,
but more dangerous to the miners
i. 3 Major Dangers
1. Mine collapsing
2. Black lung disease
3. Explosions of methane / natural gas
• Advantages of Coal:
1.It’s cheap!
2.Very abundant
3.Needs little refining after being mined
• Disadvantages of Coal:
1.Emits air pollutants (sulfur dioxide & mercury)
2.Causes acid precipitation
Petroleum / Crude Oil:
Formation of petroleum
 Comes from the decay of tiny marine
organisms that became buried on the bottom
of the ocean floor
 The heat from the Earth’s crust caused them
to become oil after millions of years
Locating and Drilling for Oil
 Most of the world’s oil is found in the Middle
East (Saudi Arabia)
 Once an oil reserve is located an oil well is
drilled
 The oil is brought to the surface by pumps and
then refined at a refinery
Refining Oil
 Heating the oil causes the petroleum to
separate from the various compounds – this
process is known as fractional distillation
o Volatile compounds have different boiling points
 Low boiling point – gasoline & jet fuel
o The compounds are collected at the various
evaporation & condensation points
o These compounds are used to make various
petroleum based products
Products from Crude Oil:
1.Gasoline – diesel
2.Motor Oil
3.Petroleum Jelly (Vaseline)
4.Gum
5.Plastics
6.Nylon Dacron
7.Kerosene
Environmental Effects of Using Oil:
 Air pollution
Sulfur dioxide, carbon dioxide, VOC’s
 Causes acid precipitation
 Causes water pollution
 Run off from streets
 Spills from oil tankers
 Spills from off-shore oil wells
Natural Gas / Methane:
 Formation
o Forms above oil reserves
o Forms in the same manner as oil




Transported through pipelines
Provides about 20% of the world’s energy
Cleanest burning fossil fuel
World’s least abundant fossil fuel
Section 2: Nuclear Energy
Nuclear Power:
 Energy stored in the nucleus of an atom
 Nuclear power plants release this energy and use
it to make steam
 The fuel in nuclear power plants is Uranium – 235
(U235)
 The nuclei of the uranium atom is bombarded
with neutrons causing it to split into two parts –
known as nuclear fission
 This splitting releases a large amount of
energy and neutrons
o The neutrons cause more nuclei to split causing a
chain reaction
 In a nuclear bomb this reaction is uncontrolled
 In a nuclear power plant this reaction is
closely controlled
• (see Fig 15 on p. 477)
How a typical nuclear power plant works
1. Energy released by the nuclear reaction heats
water in the pressurized first circuit to a very
high temperature
2. The superheated water is pumped to a heat
exchanger, which transfers the heat of the first
circuit to the second circuit. Water in the second
circuit flashes into high-pressure steam
3. Steam is directed against a turbine, setting it in
motion. The turbine sets the generator in
motion, generating electricity
4. A third circuit cools the steam from the turbine
and the waste heat is released from the cooling
tower in the form of steam
Advantages of Nuclear Energy:
1.Produces a large amount of energy and the
fuel is compact
2.Does not produce air pollution or greenhouse
gases
3.Nuclear power plants release less radioactivity
into the environment than a coal burning
plant
Disadvantages of Nuclear Energy:
1.Building and maintaining a nuclear power
plant is very expensive
2.Storage of radioactive waste (spent fuel) is
very difficult and expensive
a.Must be stored in an area that is geologically
stable for tens of thousands of years.
b.Yucca Mountain in So. Nevada (Mojave Desert
outside Las Vegas) is being studied for such
storage
3. There are a lot of safety concerns that
any accident could be very dangerous
a.Three-Mile Island (Harrisburg, PA) – the site
of the most serious nuclear accident in the
US in 1979.
b.Caused by human error & faulty equipment
c.Very little radiation escaped into the
environment
• The Future of Nuclear Power:
• Nuclear Fusion:
The combining of the nuclei of light weight
atoms creating one heavy atom and generating
a huge amount of energy
Fusion Advantage:
1. It does NOT create radioactive waste
Fusion Disadvantage:
1. In order for fusion to occur, the nuclei must be heated
to extremely high temperatures (1 million degrees
Celsius)
2. The nuclei must be maintained at very high
concentrations
3. Nuclei must be properly contained
**Achieving all three conditions simultaneously is
extremely difficult