Nonrenewable Energy Sources Chapter 12 Nonrenewable Energy Sources
What have you done today that required energy? Warm-Up Question What have you done today that required energy?
Measuring Energy Are all energy sources measured in the same way? Gallons of gasoline Cords of wood Cubic feet of natural gas How do we measure the amount of energy if each source has its own unit of measure?
British Thermal Units 1 Btu = amount of energy needed to raise the temperature of 1 lb. of water by 1 degree Fahrenheit 1 wooden kitchen match = 1 Btu 1 ounce of gasoline = 1,000 Btu’s
Btu’s Everyday, the average American uses about 890,000 Btu’s of energy In order to measure very large quantities of energy, we use the “quad”, which represents 1 quadrillion (1,000,000,000,000,000) Btu’s The U.S. uses about 1 quad of energy every 3.7 days
Energy What is the difference between renewable and nonrenewable energy sources? What percent of our energy comes from nonrenewable energy sources? Renewable energy sources?
Nonrenewable Energy Nonrenewable energy resources - fossil fuels (coal, oil, natural gas) and nuclear fuels
Source: Energy Information Agency
Energy Consumption in the U.S.
Energy Use Commercial energy sources - those that are bought and sold, such as coal, oil and natural gas Subsistence energy sources - those gathered by individuals for their own use such as wood, charcoal, and animal waste
Process of Energy Use
Efficiency of U.S. Automobiles How has automobile efficiency changed over the past 30 years?
Efficiency of U.S. Automobiles
AP Practice Problem Which of the following is not a nonrenewable energy resource? Oil Coal Natural gas Wind Nuclear fuels
Electricity Generation The burning fuel from coal transfers energy to water, which becomes steam The kinetic energy contained within the steam is transferred to the blades of a turbine, a large device that resembles a fan As the energy in the steam turns the turbine, the shaft in the center of the turbine turns the generator This mechanical motion generates electricity
Electricity Generation
AP Practice Problem Which of the following is not a nonrenewable energy resource? Oil Coal Natural gas Wind Nuclear fuels
Fuels Used for Electricity Generation in the U.S. Most coal burning power plants are about 35% efficient
Cogeneration Cogeneration - using a fuel to generate electricity and to produce heat Ex: If steam is used for industrial purposes or to heat buildings it is diverted to turn a turbine first This improves the efficiency to as high as 90%
Coal Coal - a solid fuel formed primarily from the remains of trees, ferns, and other plant materials that were preserved 280-360 million years ago Four types of coal ranked from lesser to greater age, exposure to pressure, and energy content These four types are: lignite, sub-bituminous, bituminous, and anthracite The largest coal reserves are in the United States, Russia, China, and India
Coal
Coal Coal is most abundant fossil fuel There are 3 categories of coal: Primarily used for generating electricity There are 3 categories of coal: Lignite – least desirable because of its high moisture content Bituminous – most widely used because it is most abundant and easiest to mine Anthracite – has the highest energy content and is cleanest burning, but is hard to obtain
Coal
Coal Reserves in the U.S. lignite anthracite bituminous
Coal in the World Where in the world is coal found?
Advantages and Disadvantages of Coal Energy-dense Contains impurities Plentiful Release impurities into air when burned Easy to exploit by surface mining Trace metals like mercury, lead, and arsenic are found in coal Technological demands are small Combustion leads to increased levels of sulfur dioxide and other air pollutants into the atmosphere. Economic costs are low Ash is left behind Easy to handle and transport Carbon is released into the atmosphere which contributes to climate change Needs little refining
Petroleum (Oil) Petroleum - a mixture of hydrocarbons, water, and sulfur that occurs in underground deposits Oil and gasoline make this ideal for mobile combustion, such as vehicles Formed from the remains of ocean-dwelling phytoplankton that died 50-150 million years ago Countries with the most petroleum are Saudi Arabia, Russia, the United States, Iran, China, Canada, and Mexico
Petroleum
Oil in the U.S. When was the first U.S. commercial oil well drilled? 1859 Where was it drilled? Titusville, PA
What are the top oil producing states in the U.S.? Texas (21%) Alaska (11%) California (10%) North Dakota (6%) Louisiana (3%)
Issues Related to the Use of Oil Present technology only removes 1/3 of an oil deposit Secondary recovery methods are used to recover more oil, such as forcing water or gas into wells to drive the oil out As oil prices increase, more expensive and aggressive secondary recovery methods will need to be used
Oil Drilling
Oil Derrick - starts the well
Pump - removes oil from ground
Oil Pump
Secondary Recovery Steam can be injected to recover more oil
Petroleum Products What products can be made from petroleum?
Oil Refining http://www.howstuffworks.com/oil-refining2.htm http://www.youtube.com/watch?v=9Py8-Xy9MKo&list=PLi_1unC2AWvDyoaErq3ql9l-0x_zY9hc-
Which countries are in OPEC?
Benefits of Using Oil Oil is more concentrated than coal, burns cleaner, and is easily transported through pipelines Can be used to make many products It causes less environmental damage than coal mining
Drawbacks of Using Oil Oil spills Oil well blowouts Pipelines and transportation routes Air pollution when burned
Price of Oil per Barrel (U.S.)
Source: Energy Information Agency
What we pay for in a gallon of gasoline Source: Energy Information Agency
Advantages and Disadvantages of Petroleum Convenient to transport and use Releases carbon dioxide into atmosphere Relatively energy-dense Possibility of leaks when extracted and transported Cleaner-burning than coal Releases sulfur, mercury, lead, and arsenic into the atmosphere when burned
Natural Gas Natural gas - exists as a component of petroleum in the ground as well as in gaseous deposits separate from petroleum Contains 80-95% methane and 5-20% ethane, propane, and butane
Where in the world is Natural Gas?
Fracking http://www.youtube.com/watch?v=k3n7sPYytQY&list=PLi_1unC2AWvBsaE-EjIbfhiC6tnNx4VDF
Advantages and Disadvantages of Natural Gas Contains fewer impurities and therefore emits almost no sulfur dioxide or particulates When unburned, methane escapes into the atmosphere Emits only 60% as much carbon dioxide as coal Exploration of natural gas has the potential of contaminating groundwater
Other Fossil Fuels Oil sands - slow-flowing, viscous deposits of bitumen mixed with sand, water, and clay Bitumen (tar or pitch) - a degraded type of petroleum that forms when a petroleum migrates close to the surface, where bacteria metabolize some of the light hydrocarbons and others evaporate
Hubbert Curve Hubbert curve - a graph that shows the point at which world oil production would reach a maximum (“peak oil”) and the point at which we would run out of oil
Future Use of Fossil Fuel Use If current global use continues, we will run out of conventional oil in less than 40 years Coal supplies will last for at least 200 years, and probably much longer
Nuclear Energy Nuclear Fission - a nuclear reaction in which a neutron strikes a relatively large atomic nucleus, which then splits into two or more parts
Uranium Fuel Pellets Uranium Ore U-235 is more desirable because it’s easier to split (fission) Enrichment process increases the amount of U-235 Uranium Ore 99.3% of all uranium atoms are the isotope U-238 Remaining 0.7% are U-235
Fission A nuclear power plant converts the energy contained within the nuclei of atoms into electrical energy U-235 absorbs a neutron to become highly unstable U-236 U-236 splits and releases a tremendous amount of heat energy
Nuclear Fission
Nuclear Reactors
Nuclear Reactors Fuel rods - the cylindrical tubes that house the nuclear fuel used in a nuclear power plant Nuclear power plants work by using heat from nuclear fission to heat water This water produces the steam to turn the turbine, which turns a generator Control rods - cylindrical devices that can be inserted between the fuel rods to absorb excess neutrons, thus slowing or stopping the fission reaction
Nuclear Energy in the World Nuclear power plants generate about 22% of the United States’ electricity In comparison: 75% in France 46% in Sweden 43% in Ukraine 39% in South Korea 30% in Germany 30% in Japan
Nuclear Power Plants in the U.S.
Nuclear Power Plant Meltdowns In 1986, the Chernobyl (Ukraine) nuclear reactor exploded 50 tons of radioactive material spewed into the surrounding area, contaminating millions of acres of forest. Forced the evacuation of at least 30,000 people Eventually caused thousands to die from cancer and other illnesses
Nuclear Waste Radioactive waste - once the nuclear fuel can not produce enough heat to be used in a power plant but it continues to emit radioactivity This waste must be stored in special, highly secure locations because of the danger to living organisms
Nuclear Waste High-level radioactive waste - the form used in fuel rods Low-level radioactive waste - the protective clothing, tools, rags, and other items used in routine plant maintenance
Nuclear Fusion Nuclear fusion - occurs when lighter nuclei are forced together to produce heavier nuclei and heat is released Ex: the reaction that powers the Sun and other stars Fusion is a promising, unlimited source of energy in the future, but so far scientists have had difficulty containing the heat that is produced
Advantages and Disadvantages of Nuclear Energy No air pollution is produced Possibility of accidents Countries can limit their need for imported oil Disposal of the radioactive waste