Non Renewable Energy Chapter 12 5/14/2018 2:00 AM Non Renewable Energy Chapter 12 © 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries. The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

Nonrenewable Energy Nonrenewable energy resources- fossil fuels (coal, oil, natural gas) and nuclear fuels.

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

Overall Fuel Efficiency of U.S. Automobiles

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 energy.

Electricity Generation

Energy Efficiency Most coal burning power plants are about 35% efficient.

Cogeneration Cogeneration- using a fuel to generate electricity and to produce heat. Example- 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

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 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

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 to 95 percent methane and 5 to 20 percent ethane, propane, and butane. Advantages Disadvantages 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. Oil Shale-The term oil shale generally refers to any sedimentary rock that contains solid bituminous materials (called kerogen) that are released as petroleum-like liquids when the rock is heated in the chemical process of pyrolysis. Oil shale was formed millions of years ago by deposition of silt and organic debris on lake beds and sea bottoms. 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. “Fracking”- is a well stimulation technique in which rock is fractured by a pressurized liquid. The process involves the high-pressure injection of 'fracking fluid' (primarily water, containing sand or other proppants suspended with the aid of thickening agents) into a wellbore to create cracks in the deep-rock formations through which natural gas, petroleum, and brine will flow more freely.

Hydro- Fracturing

Tar Sands of Canada

The Hubbert Curve Hubbert curve- a graph that shows the point at which world oil production would reach a maximum and the point at which we would run out of oil.

The Future of Fossil Fuel Use If current global use continues, we will run out of conventional oil in less than 55 years, according to a new BP estimate. Coal supplies will last for at least 200 years, and probably much longer.

Nuclear Energy Fission- a nuclear reaction in which a neutron strikes a relatively large atomic nucleus, which then splits into two or more parts.

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.

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

Radioactive 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. 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 Energy and the Environment Nuclear fuel cycle includes: Mining and processing of uranium to controlled fission Reprocessing of spent fuel Decommissioning of power plants Disposal of radioactive waste Throughout the cycle radiation can enter and affect the environment

Nuclear Power Plant Accidents US Nuclear Regulatory Commission Sets performance goal for a single reactor at 0.01% (1 in 10,000 chance of core meltdown) If there were 1,500 plants a melt down would be expected every seven years Unacceptable risk Two well-known accidents Three-Mile Island Occurred March 28, 1979 near Harrisburg, PA Malfunction of a valve resulted in partial core meltdown Intense radiation released to interior of containment structure Small amount of radiation released into environment Chernobyl Occurred April 26, 1986 in Cherbobyl, Soviet Union Worst accident in history of nuclear power generation Failure in cooling waters Reactor overheated melting the uranium fuel Explosions removed top of building Fires produced a cloud of radioactive particles

Radioactive Waste Management By-products are expected when electricity is produced at nuclear reactors Three general categories Mine tailings 20 million metric tons of abandoned tailings will continue to emit radiation for 100,000 years Low-level waste Transuranic waste High-level waste

Yucca Mountain Nuclear Waste Depository Nuclear Waste Policy Act of 1982 Initiated high-level waste disposal program Department of Energy investigated several sites To be disposed of underground in deep geologic waste repository Yucca Mountain only site being evaluated Use of site begins in 2010? Extensive scientific evaluations of Yucca Mountain carried out Remain controversial Concerned that natural processes might allows radiation to escape Major question as to how accurate long-term predictions are

The Future of Nuclear Energy Advocates argue that nuclear power is good for the environment It does not produce potential global warming through release of carbon dioxide It does not cause acid rain If breeder reactors are developed the amount of fuel will be greatly increased However, can it really ever be “safe”

Fusion Nuclear fusion- the reaction that powers the Sun and other stars. This occurs when lighter nuclei are forced together to produce heavier nuclei and heat is released. Fusion is a promising, unlimited source of energy in the future, but so far scientists have had difficulty containing the heat that is produced.