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CHAPTER 17: NONRENEWABLE ENERGY
What Is Energy? The ability to do work or cause a change
Kinetic energy: Due to motion
Potential energy: Due to an object’s position or shape
Different fuels for different uses
•Would coal be a good transportation fuel?•Would oil be good to use on your stovetop to heat up some pasta?Each fuel has
its best use•Electricity•Transportation fuel•Heating•Cooking•Running machines
Fuels for different purposes
Five main purposes for fuels Cooking Transportation Manufacturing Heating/cooling ElectricitySome fuels better for some purposes Why is coal not used to fly planes?
How Do We Evaluate Which Fuel To Use?
How should we decide what fuel to use for energy?Political, Economic, Energy Companies, Societal Debate
Evaluating Energy Choices1. Costs2. Environmental
Impacts3. Availability in near
future and long term4. Governmental
Incentives5. National and Global
Security6. Terrorism
Energy Sources
Renewable: Nearly always available or replaceable in a relatively short time; includes sunlight, wind, flowing water, heat from Earth
Nonrenewable: Cannot be replaced in a reasonable time; includes fossil fuels and nuclear energy
Evaluating Energy Resources
Non-renewable energy: 84% of world commercial
energy (78% from fossil fuels, 6% nuclear)
Oil, coal, natural gas, nuclear
Non-renewable energy: 84% of world commercial
energy (78% from fossil fuels, 6% nuclear)
Oil, coal, natural gas, nuclear
Evaluating Energy Resources
Renewable Energy Sources:
16% of world’s commercial energy resources.
10% biomass, 5% hydro, and 1% combo of geothermal, wind and solar.
Commercial Energy Use By Source 2002
Global Energy Consumption
U.S. Energy Consumption
History of U.S. Consumption
What are fossil fuels?
Fossil fuels are the remains of ancient organisms changed into solid (coal), liquid (oil) or gas (natural gas) Why called fossil
fuels? Most energy today
is from these 3
What are fossil fuels?
Why are fossil fuels nonrenewable?
TRAPPED CHEMICAL POTENTIAL ENERGY FROM ANCIENT PHOTOSYNTHESIS
What are fossil fuels? How is using fossil fuels like using
energy from “ancient” solar energy? Your life powered by sun that arrived
on Earth millions of years ago?
Electricity – Power on Demand
Coal formation
Section COAL
History of Old King Coal
After firewood, coal was the major source of energy.
End of 1800s coal is the worlds dominant fuel.
Steam Engines Heating Cooking Industry
History of Old King Coal
By 1920s, coal provided 80% of US energy.
Powered the industrial revolution
Caused a great deal of air pollution.
What is coal?
Coal is a solid fuel formed in several stages from remains of buried plants and animals.
Consists mostly of carbon and trace amounts of sulfur, mercury and radioactive materials.
What is coal?
Anthracite is the most desirable form of coal (98% carbon)
Takes longer to form
More expensive.
Coal Formation and Types
How is coal extracted? Surface Mining: Area Strip Mining Contour Strip Mining Mountaintop Removal
Underground Mining
Large environmental impact from different mining techniques.
Coal Mining
How is coal used?
Coal provides 51% of current U.S. electricity. (62% worldwide)
Used to make ¾ of worlds steel.
A typical 1,000 Megawatt power plant uses 8,000 tons of coal every day…1 mile long train worth of coal every day.
How is coal used?
91% of coal in U.S. is used for power production.
Not useful for transportation energy needs.
Where in the world is coal found?
U.S. has 1/4th of the world proven reserves. (16% Russia, 12% China)
U.S. and China are 2 largest users.
U.S. is able to export about 4% a year.
Where is the coal?
How long will coal last?
According to USGS…
U.S. reserves could last 300 years at current rate of consumption…or 64 years if consumption grows by 4% a year.
World’s most abundant fossil fuel.
U.S. Energy Projections
Coal Advantages
Most abundant fossil fuel.
Lots of energy Relatively
inexpensive. U.S. has plenty of
it for a while. Power Plants
relatively cheap to build.
Coal Disadvantages
High environmental impact (air, water, land, acid rain)
Global Warming, high CO2 emissions
Toxic Mercury and radioactivity
Dangerous to mine
Oil Rules!!! What is crude oil?
Petroleum, or crude oil is a thick, gooey liquid consisting of many combustible hydrocarbons.
Formed over millions of year from decaying organic materials buried under the seafloor and subjected to extreme temperatures and pressure.
Oil Rules!!! What is crude oil?
Crude oil and natural gas often found together in deep deposits in pores and cracks.
Found using sophisticated equipment. Usually only 30-35% is extractable Higher prices mean more can be extracted.
Oil Rules!!! Transportation
How crude oil is transported:
Pipelines Trucks Oil Tankers
Refining crude oil. Based upon their boiling points, components are removed in giant distillation column.
In US refining accounts for 8% of our energy consumption
1 barrel is 42 gallons
Oil, Who Has It?Eleven OPEC
countries contain 78% of world’s proven oil reserves
Oil is the world’s largest business.
Saudi Arabia 25%Canada 15%Iraq 11%, UAE 9.3%
Oil, Who Has It?
U.S.: Uses 26% Produces 2.9% Import 60% (36%
in 1973)2003 $99 billion import
bill. 2/3 for transportation
North American Energy Resources
Fig. 17-9 p. 357
Offshore oil accounts for 1/4th of U.S. Oil Production. 9 of 10 barrels come from the Gulf.
US Oil Supply and Consumption.
Oil, What Is Left?
Most energy expert believe there are about 1,050 billion barrels left.
Peak Production This Decade
Rising Demand, Dwindling Supply = Higher Prices
Oil, What Is Left?
Ways of extending oil supplies:
Increase CAFÉ Find new reserves Taxing Conservation Increased use of
other sources.
Advantages of Oil
We are used to it Have a system to
distribute and use it set up
High energy level Used in many
products Relatively low cost
Disadvantage of Oil
Running Out (Nonrenewable)
U.S. has little Dependent of
foreign sources POLLUTION Global Warming International
Politics
What is natural gas?Mainly methane CH4
Also Ethane C2H6
Propane C3H8
Butane C4H10
Formed like oil from buried animals and plants millions of years ago.
Where is it found?
Deposits usually found above oil deposits.
In past was seen as unwanted waste and burnt off.
Who has natural gas?
Russia (31%) and Iran (15%) have almost ½ of world’s reserves.
Reserves could last 62-125 years worldwide.
Geologist expect to find more.
U.S. Natural Gas
U.S. supplies should last 55-80 years depending upon demand.
Supplies have been declining for years.
Canada???
How is it used?
53% of heat in U.S. homes
16% of electricity and growing quickly
Hot water heaters Can be used in
vehicles
Advantages of Gas
Cleaner burning than coal or oil.
Emits far fewer CO2 per energy units
More efficient energy producer and plants are cheaper to build
Disadvantages of Natural Gas
Nonrenewable Highly Flammable Air pollution Global Warming Can be a
challenge to transport
Consequences of Fossil Fuel Usage
Carbon Dioxide Emissions Per Unit of Energy
Pollution, Climate Change, and Public Health
• Burning fossil fuels releases carbon dioxide, which contributes to global climate change.
• When coal and oil burn, sulfur dioxide and nitrogen oxides are released, which contribute to smog and acid deposition.
• Oil spills, equipment ruptures, and oil in runoff pollute waterways, oceans, and coastal areas.
• Coal-fired power plants release mercury, which harms human health. Crude oil contains trace amounts of lead and arsenic.
Damage Caused by Extracting Fuels
• Mining:
• Humans risk lives and respiratory health.
• Ecosystems are damaged by habitat destruction, extensive erosion, acid drainage, and heavy metal contamination downslope of mines.
• Oil and gas extraction:
• Roads and structures built to support drilling break up habitats and harm ecosystems.
• The longterm consequences of accidents can be uncertain or unpredictable Acid drainage from a coal mine
Dependence on Foreign Sources
• Fossil fuels are not evenly distributed over the globe, so some countries must import fuel sources.
• Nations that import fuel may be vulnerable to changes in fuel prices set by suppliers.
• Nations can import less fuel by developing domestic oil sources and renewable energy sources.
Energy Conservation
• Practice of reducing energy use to make fossil fuels last and to prevent environmental damage
• Transportation: Gas-efficient cars and higher gas prices could help conserve energy in the U.S.
• Personal choices: Individuals can save energy by turning off lights, taking public transit, and buying energy-efficient appliances.
How does a nuclear fission reactor work?
Isotopes of uranium and plutonium undergo controlled nuclear fission.
U235 and Pt239
(U contains 92 Protons, how many
neutrons???)
Fission Chain Reaction, splitting the nucleus, releasing heat to produce steam
Nuclear Fusion
• Joining two atomic nuclei to form one nucleus
• Releases much more energy than fission
• Currently impractical because very high temperatures are needed, but scientists continue exploring fusion for our future energy needs
How does a nuclear fission reactor work?
Core Reactor: 35,000 to 70,000 fuel rods
Fuel pellets of 97% non-fissionable U238 and 3% fissionable U235
Control rods of Boron and Cadmium
Coolant: water Containment
vessel
How does a nuclear fission reactor work?
“Spent” fuel rods usually stored onsite in huge pools of water
Must be stored safely for 10,000 to 24,000 years
Multiple safety layers at plants.
How does a nuclear fission reactor work?
The heat produced by the splitting of uranium is used to generate electricity by spinning turbines.
Plants must be in continual operation
Benefits and Costs of Nuclear Power
Benefits Costs
No air pollution Expensive to build and maintain
Requires little uranium fuel and little mining
Catastrophic accidents are possible.
Under normal conditions, nuclear power plants are safer for workers than coal-burning power plants.
Nuclear waste must be stored for thousands of years.
Chernobyl
What is the nuclear fuel cycle?
Fuel Cycle Includes: Mining uranium Processing fuel
“enrichment” Using fuel in
reactor Storing highly
radioactive waste for thousands of years
What is the nuclear fuel cycle?
After 15-60 years reactors become contaminated with radioactive materials and parts become worn out.
Transporting nuclear waste for storage 10,000 years or more
What is the history of nuclear technology?
Following WW II great interest in showing how atomic age could benefit humankind
Tremendous government subsidies and research
Government paid ¼ of cost of building first reactors.
Government paid insurance
What is the history of nuclear technology?
1960s and 70s plans for many U.S. plants
1975 – 53 plants operating (9% of U.S. electricity) another 170 plants planned
1978 last plant to be built was ordered – great unease about plants
What is the history of nuclear technology?
1979 Three-Mile Island, PA
1986 Chernobyl (still a problem today)
2011 Japanese Plant Meltdown after Tsunami
Globally plants continue to be built (441 in operation, 23 being built)
Where is it used today?
U.S.In 2010: 103 in operation 21% of countries
electricity (huge plants)
US Energy Information Agency predicts 27% fewer plants in 2020
Where is it used today?
Globally: 441 plants (32
under construction)
17% of world’s electricity
Growing 2.5% yearly
Leading countries: Lithuania 80% France 78%
Locations of U.S. Nuclear Power Plants
Advantages of Nuclear Power
Large Fuel Supply Little Air Pollution
and CO2 emissions Moderate to low
water and land environmental impact
Low risk of accidents
Disadvantages of Nuclear Power
High cost of building and operating plants
Possibility of catastrophic accidents
No long-term solutions for waste
Spreads knowledge of nuclear weapon technology
Terrorist Attacks
To Think About…
1) If you were in charge, what energy source would you
recommend? 2) What is the future of fossil
fuels?3) What can our government do
to encourage energy conservation?
