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Unit 11: 

Unit 11 Chapters 15,16,and 22 By: Jean Young Maria Reyes

Nonrenewable Energy Resources: 

Nonrenewable Energy Resources Evaluating Energy Resources Oil Natural Gas Coal Nuclear Energy


Evaluating Energy Resources Some 99% of the energy we used to heat the earth and our buildings comes directly from the sun. The remaining 1%, the portion we generate to supplement the solar input, is commercial energy sold in the marketplace. The most important supplemental source of energy for developing countries is potentially renewable biomass. Fuelwood--main source of energy for heating and cooking for roughly half of the world’s population


Types (continued) The United States is the worlds largest user of energy. With only 4.6% if the population, it uses 24% of the worlds energy, 93% from nonrenewable fossil fuels (85%) and nuclear energy (8%). India, with 17% of the world’s people, uses only about 3% of the world’s commercial energy.

How Should We Evaluate Energy Resources?: 

How Should We Evaluate Energy Resources? Our current dependence on nonrenewable fossil fuels is the primary cause of air and water pollution, land distribution, and projected global warming. Affordable oil, the most widely used energy resource in developed countries, will probably be depleted within 40-80 years and must be replaced by other energy resources. Choices include: more energy from the sun, wind, flowing water, biomass, heat stored in the earth’s interior, and hydrogen gas by making the transition to a renewable energy or solar age.

Evaluation (Continued): 

Evaluation (Continued) Others say we should burn more coal and synthetic liquid and gaseous fuels made from coal. Some feel that natural gas is the answer. Others think the answer is nuclear power.

What is Net Energy? The Only Energy That Really Counts: 

What is Net Energy? The Only Energy That Really Counts Each time we use energy to perform a task, some of it is always wasted and is degraded to low-quality energy. Net energy--the total useful energy resource over its lifetime minus the amount of energy used (1st law of energy), automatically wasted (2nd law of energy), and unnecessarily wasted in finding, processing, concentrating, and transporting it to users.

Net energy (continued): 

Net energy (continued) Net energy ratio: ratio of energy produced to the useful energy used to produce it. The higher the ratio, the greater the net energy yield, and when the energy is less than 1, there is a net energy loss.



What is crude oil, and how is it extracted and processed?: 

What is crude oil, and how is it extracted and processed? Petrolium(crude oil)--fossil fuel produced by the decomposition of deeply buried dead organic matter from plants and animals under high temperatures and pressures over millions of years. Consists mostly of hydrocarbons, with small amounts of sulfur, oxygen, and nitrogen impurities. Primary oil recovery--drilling a well and pumping out the oil that flows by gravity into the bottom of the well. Secondary oil recovery--after the flowing oil has been removed, water can be injected into nearby wells to force some of the remaining heavy oil to the surface.

Crude Oil (Continued): 

Crude Oil (Continued) Enhanced (tertiary) oil recovery--steam or CO2 gas is used to force some of the heavy oil into the well cavity for pumping to the surface. Refinery--where oil is heated and distilled in gigantic columns to separate it into liquids components with different boiling points. petrochemicals--some of the products of oil distillation that are used as raw materials in industrial organic chemicals, pesticides, plastics, synthetic fibers, paints, medicines, and many other products.

Who has the world’s oil supplies?: 

Who has the world’s oil supplies? Reserves--identified deposits from which oil can be extracted profitably at current prices with current technology. The 13 countries that make up OPEC have 67% of the world’s reserves. The U.S. has 2.3% of the world’s oil reserves but uses 30% of the oil extracted each year, 65% of it for transportation.

How long will oil supplies last?: 

How long will oil supplies last? The reserves are considered economically depleted when 80% of the supply has been used; the remaining 20% is considered too expensive to extract. The reserves might be depleted in 35-84 years, depending on how rapidly it is used. Projections could be flawed because they: Rely on distorted estimates of reserves Assume that production will remain constant Assume falsely that new technologies will allow tertiary recovery of 40-60% of the oil in existing wells instead of the usual 30%.

What are the pros and cons of conventional oil? Pros Cons: 

What are the pros and cons of conventional oil? Pros Cons Oil is still cheap; when adjusting for inflation it costs about the same as it did in 1975. It is easily transported within and between countries and, when extracted from easily accessible deposits, it has a high net energy yield. Oil can cause pollution and environmental degradation throughout its life cycle of extraction, processing, transporting, and use. The oil-drilling process causes land disturbance, which can accelerate erosion. It produces waste materials (soil, rock, and drilling muds removed from the hole), and can pollute soil and water if some of the oil is spilled. Leakage of drilling muds can contaminate nearby surface and groundwater. Burning fuel oil and gasoline releases heat-trapping carbon dioxides which could alter global climate, and other air pollutants such as sulfur dioxide and nitrogen oxides that harm people, crops, trees, fish, and other species.

What are the pros and cons of using heavy oil produced from oil shale?: 

What are the pros and cons of using heavy oil produced from oil shale? Oil Shale--fine grained rock that contains a solid, waxy mixture of hydrocarbon compounds called kerogen. After being removed by surface mining, the shale is heated above ground in a retort to vaporize the kerogen. Shale oil--heavy, slow forming, dark brown material formed by condensing the kerogen vapor.

Problems with shale oil: 

Problems with shale oil It has a lower net energy yield than does conventional oil because it takes the energy from almost half a barrel of conventional oil to extract, process, and upgrade one barrel of shale oil. Processing the oil requires large amounts of water, which is scarce in the semiarid locales where the richest deposits are located. Surface mining of shale oil tears up the land, leaving mountains of shale rock (which expands when heated). Salts, cancer causing substances, and toxic metal compounds can be leached from the processed shale rock into water supplies. Some of these problems can be reduced by extracting shale oil underground, but this method is too expensive and produces more sulfur dioxide air pollution than does surface processing.

Natural gas : 

Natural gas Natural gas--mixture of 50-90%by volume of methane, smaller amounts of of heavier hydrocarbons, and highly toxic hydrogen sulfide. Conventional natural gas--lies above most reservoirs of crude oil. Unconventional--coal beds, Devonian shale rock, deep underground deposits of tight sands and deep zones that contain natural gas dissolved in hot water. Liquefied petroleum gas (LPG)--propane and butane gasses that are liquefied when a natural gas field is tapped. Liquefied natural gas--natural gas that is converted at very low temperatures of -184°C (-300°F)

Natural Gas (continued): 

Natural Gas (continued) Combined-cycle natural gas systems--can produce electricity much more efficiently and cheaply than burning coal or oil or using nuclear power. Cogeneration--burning natural gas to produce high-temperature heat and electricity, further improving the efficiency of this fuel.


Coal Coal--solid, rocklike fossil fuel that forms in several stages as the buried remains of ancient swamp plants that died during the Carboniferous period were subjected to intense pressure and heat over many millions of years. Three types: Lignite-brown coal, bituminous coal-soft coal, and anthracite-hard coal. Surface mining-bulldozers and huge earth moving machines remove soil and rock. Overburden-the soil and rock that is removed. Area strip mining-used on fairly flat terrain. Contour strip mining-used on hilly or mountainous terrain. Open pit mining-a form of surface mining where thick beds of coal fairly near the surface are removed by digging a deep pit to remove the coal.

Coal (continued): 

Coal (continued) Electrostatic precipitators-used in smokestacks to remove the particulate matter when removing air pollutants. Scrubbers-remove most of the sulfur dioxide, formed when oxygen gas combines with sulfur impurities in the burning coal. Identified world reserves of coal should last at least 220 years at current usage rates, but only 65 years if the usage rates increase 2% per year. Unidentified coal reserves are projected to last about 900 years at the current consumption rate, but only 149 years if the usage rate increases 2% per year. Coal has a high net energy yield.

Coal (continued): 

Coal (continued) Fluidized-bed combustion-new way that has been developed to burn coal more cleanly and efficiently. Environmental costs-were 5.7 cents per kW/hr, 5 cents for nuclear, 2.7 cents for oil, 1 cent for natural gas, under .7 cents for biomass, less than .4 cents for solar cells, and under .1 cent for wind and geothermal Synthetic natural gas-solid coal can be converted into this by coal gasification, into hydrogen gas or into a liquid fuel such as methanol or synthetic gasoline by coal liquefaction. These are called synfuels, and they can be transported by pipeline, and they produce much less air pollution than solid coal. They can be burned to produce high-temperature heat and electricity, to heat houses and water, and propel vehicles.

Nuclear Energy: 

Nuclear Energy Began developing nuclear power plants for three reasons: The Atomic Energy Commission promised the companies that nuclear power would produce electricity at a much lower cost than coal and other alternatives. The government paid about a quarter of building the first group of commercial reactors After U.S. insurance companies refused to cover more than a small part of the possible damages from a nuclear power-plant accident Congress passed the Price-Anderson act which protects the nuclear industry and utilities from significant liability to the general public in case of accidents.

Nuclear Fission Reactor: 

Nuclear Fission Reactor Light water reactor-produce about 85% of the world’s nuclear-generated electricity. Has several key parts: Core, control rods, moderator, and a coolant.


Reactors After about 15-40 years of operation, a nuclear reactor becomes dangerously contaminated with radioactive materials and many of its parts are worn out. Then the plant must be decommissioned by: Dismantling it and storing its large volume of highly radioactive materials in high-level nuclear waste storage facilities. Putting up a physical barrier and setting by full time security of 30-100 years until the plant is dismantled. Enclosing the entire plant in a tomb that must last for several thousand years.

Low-level radioactive waste: 

Low-level radioactive waste Low-level radioactive wastes- give off small amounts of ionizing radiation and must be stored safely for 100-500 years before decaying to levels that don’t pose an unacceptable risk to public health and safety. Bureaucratic semantic solution- solve the problem of low-level radioactive waste by officially redefining it as essentially non-radioactive.

High-level radioactive waste: 

High-level radioactive waste High-level radioactive waste-give off large amounts of ionizing radiation for a short time and small amounts for a long time. Proposed methods of disposal: Bury it deep underground Shoot it into space or into the sun Bury it under the Antarctic ice sheet or the Greenland ice cap Dump it into descending seduction zones in the deep ocean Bury it in thick deposits of mud on the deep ocean floor in areas that tests show have been geologically stable for 65 million years Change it into harmless or less harmful isotopes.

Nuclear reactors and the spread of nuclear weapons: 

Nuclear reactors and the spread of nuclear weapons We already live in a world with enough nuclear weapons to kill everyone on the earth 40 times over--20 times if current nuclear arms reduction agreements are carried out.

Can we afford nuclear power?: 

Can we afford nuclear power? Extremely high-cost: the major reason utility officials, investors, and most governments are shying away from nuclear power. Some analysts argue that we should continue some low-level government funding of research and development and pilot plant testing of new reactor designs to keep open the option open. There may be an urgent need to sharply reduce the fossil-fuel greenhouse gas or because improved energy efficiency and renewable energy options may fail to keep up with demands for electricity.

Energy efficient and renewable energy resources: 

Energy efficient and renewable energy resources The importance of improving energy efficiency Ways to improve energy efficiency Direct use of solar energy for heat and electricity Producing electricity from moving water and from heat stored in water Producing electricity from wind Producing energy from biomass The solar-hydrogen revolution Geothermal energy Solutions: A sustainable energy strategy

Energy efficiency : 

Energy efficiency 84% of all commercial energy used in the United States is wasted. People in the United States unnecessarily waste as much energy as two-thirds of the worlds population consumes. Energy efficiency--percentage of total energy input that does useful work in an energy conversion system. Life-cycle cost--initial cost plus lifetime operating costs (for machines)

Reducing energy waste: 

Reducing energy waste Reducing energy waste: Makes nonrenewable fossil fuels last longer Gives us more time to phase in renewable energy resources Decreases dependence on oil imports Lessens the need for military intervention in the oil-rich but politically unstable Middle East Reduces local and global environmental damage Is the cheapest and quickest way to slow projected global warming Saves more money, provides more jobs, improves productivity, and promotes more economic growth per unit of energy than other alternatives Improves competitiveness in the international marketplace.

Saving energy in industry: 

Saving energy in industry Cogeneration--the production of two useful forms of energy from the same fuel source. 8 years of cogeneration could produce more energy than all U.S. nuclear power plants, and much more cheaply. About 60-70% of the electricity used in U.S.industry drives electric motors, most of which are run at full speed with their output throttled to match their task.

The Negawatt Revolution: 

The Negawatt Revolution Demand-side management (negawatt revolution)--reducing the demand for electricity. To reduce demand, utilities give customers cash rebates for buying efficient lights and appliances, free home-energy audits, low-interest loans for home weatherization or industrial retrofits, and lower rates to households or industries meeting certain energy-efficient standards.

Saving energy in transportation: 

Saving energy in transportation The most important way to save energy and money in transportation is to increase the fuel efficiency of motor vehicles. Electric cars--might help reduce dependence on oil, especially for urban commuting and short trips. Elsewhere pollution--air pollution and nuclear wastes produced by using coal and nuclear power to produce the electricity needed to recharge their batteries daily. Ecocars--cars that run on hybrid electric-internal combustion. Another way to save energy is to shift to more energy-efficient ways to move people and freight.

Saving energy in buildings: 

Saving energy in buildings Superinsulated houses--so heavily insulated and so airtight that heat from direct sunlight, appliances, and human bodies warms them, with little or no need for backup heating. Using straw, an annual renewable agricultural residue often burned as a waste product, for the walls reduces the need for wood and thus slows deforestation. Another way to save energy is to use the most energy-efficient ways to heat houses.

Saving energy in buildings (cont.): 

Saving energy in buildings (cont.) The energy efficiency of existing houses can be improved by significantly by adding insulation, plugging leaks, and installing energy-saving windows. We can also use the most energy-efficient ways to heat household water. Setting higher energy-efficiency standards for new buildings would also save energy. Another way to save energy is to buy the most energy-efficient appliances and lights.

Advantages of solar energy: 

Advantages of solar energy About 92% of the known reserves and potentially available energy resources in the United states are renewable energy from the sun, wind, flowing water, biomass, and earth;s internal heat. The other 8% of potentially available domestic energy resources are coal (5%), oil (2.5%), and uranium (.5%).

Solar energy used to heat houses and water: 

Passive solar heating system--captures sunlight directly within a structure and converts it into low-temperature heat for space heating. Can provide at least 70% of a residential buildings heating needs and at least 60% of its cooling needs. Can provide for 60% of a commercial buildings energy needs. Active solar heating system--specially designed collectors absorb solar energy and a fan or a pump supplies part of the buildings space-heating or water heating needs. Solar energy for low-temperature heating of buildings, whether collected actively or passively, is free and the net energy yield is moderate to high. Owners of passive and active heating systems need solar legal rights-laws to protect others from building structures that block their access to sunlight. Solar energy used to heat houses and water

Cooling houses naturally: 

Cooling houses naturally Passive cooling can be provided for by blocking the high summer sun with deciduous trees, window overhangs, or awnings. Windows and fans can be used to take advantage of breezes and keep air moving. Earth tubes--simple plastic plumbing pipes with a diameter of 10-15 cm buried about .6 meters apart and 3-6 meters deep, that pipe cool and partially dehumidified air into an energy-efficient house at a cost of a few dollars per summer.

Solar energy used to generate high-temperature heat and electricity: 

Solar energy used to generate high-temperature heat and electricity Solar thermal systems--collect and transform radiant energy from the sun into high-temperature thermal energy, which can be used directly or converted into electricity. Central receiver system (power tower)--huge arrays of computer controlled mirrors (heliostats) track the sun and focus sunlight on a central heat-collection tower. Solar thermal plant (distributed receiver system)--sunlight is collected and focused on oil-filled pipes running through the middle of curved solar collectors. Parabolic dish collectors--collectors track the sun along two axis and are generally more efficient. Nonimaging optical solar concentrator--the suns rays are allowed to scramble instead of being focused on a particular point.

The PV revolution: 

The PV revolution Photovoltaic cells (solar cells)--a transparent silicon wafer thinner than a sheet of paper. Solar-electric window--incorporates solar cells into a semitransparent glazing that simultaneously generates electricity and provides filtered light for residents during daylight hours.

Producing electricity from moving water: 

Producing electricity from moving water Large-scale hydropower project--a high dam is built across a large river to create a reservoir. Small-scale hydropower project--a low dam with no reservoir is built across a small stream. Pumped hydropower systems--falling water supplies extra power mainly during times of peak electricity demand.

Producing electricity from heat stored in water: 

Producing electricity from heat stored in water Ocean thermal energy conversion--the use of the large temperature differences (between the cold, deep waters and sun-warmed surface waters) of tropical oceans. Saline solar ponds--usually located near inland saline seas or lakes in areas with ample sunlight, can produce electricity from heat stored in layers of increasing concentrations of salt. Freshwater solar ponds--a shallow hole is dug and lined with concrete. A number of large plastic bags each with a few cm of water are placed in the hole and covered with fiberglass insulation panels.

Electricity from wind: 

Electricity from wind Wind power is a virtually unlimited source of energy at favorable sites. The global potential of wind power is about five times current world electricity use. With moderate to fairly high net energy yield, these systems emit no heat trapping carbon dioxide or other air pollutants.

Electricity from wind (drawbacks): 

Electricity from wind (drawbacks) It is economical primarily in areas with steady wind. Visual pollution and noise. Large wind farms might interfere with the flight patterns of migratory birds.

Energy from biomass: 

Energy from biomass Biomass--organic matter in plants produced through photosynthesis. Biofuels--converted biomass that has been burned directly as a solid fuel. Biogas--a mixture of methane, carbon dioxide, liquid ethanol, and liquid methanol. Biogas digesters--convert organic plant and animal waste into methane fuel for heating and cooking.

Energy from biomass (cont.): 

Energy from biomass (cont.) Ethanol--made from sugar and grain crops by fermentation and distillation. Gasohol--mixture of gasoline and ethanol which can be burned in conventional gasoline engines. Methanol--made mostly from natural gas but can be made from wood, wood wastes, agricultural wastes, sewer sludge, garbage, and coal. Biomass plantations--one way to produce biomass fuel by planting large numbers of fast growing trees.

Burning agricultural and urban wastes: 

Burning agricultural and urban wastes In agricultural areas, crop residues and animal manure can be collected and converted into biofuels. Bagasse--the residue left after sugarcane harvesting and processing.

Solar-hydrogen revolution: 

Solar-hydrogen revolution Solar-hydrogen revolution--would eliminate the air and water pollution caused by extracting, transporting, and burning fossil fuels. Photovoltaic-photochemical cell--uses sunlight to split hydrogen and oxygen at an efficiency of 12.4%. Fuel cell--hydrogen and oxygen gas combine to produce electrical current. Hydrogen corridor--group of areas where hydrogen powered vehicles are being tested.

Geothermal Energy: 

Geothermal Energy Geothermal Energy--heat contained in underground rocks and fluids. Dry steam--steam with no water droplets. Wet steam--mixture of steam and water droplets. Molten rock--magma Hot dry-rock zones--molten rock that has been penetrated to the earth’s crust heats subsurface rocks to high temperature. Warm-rock reservoir deposits--low-to-moderate temperature which could be used to preheat water and run heat pumps for space heating and air conditioning.

Solutions: A sustainable energy strategy: 

Solutions: A sustainable energy strategy The best short-term, intermediate, and long-term alternatives are a combination of improved energy efficiency and greatly increased use of locally available renewable energy resources. Future energy alternatives will probably have low to moderate net energy yields and moderate to high development costs. Because there is not enough financial capital to develop all energy alternatives, projects must be chosen carefully We cannot and should not depend on a single nonrenewable energy resource such as oil, coal, natural gas,or nuclear power.

Solid and hazardous waste: 

Solid and hazardous waste Wasting resources: The high-waste approach. Producing less waste and pollution: reducing throughput. Recycling Detoxicating, burning, burying, and exporting wastes. Lead, dioxins, and chlorine. Hazardous-waste regulation in the United States.

Solid waste: 

Solid waste Solid waste--any unwanted or discarded material that is not liquid or gas. About 95% of the solid waste in the United States comes from mining, oil and natural gas production, agriculture, and industrial activities used to produce goods and services for consumers. Municipal solid waste--garbage.

Living in a high waste society: 

Living in a high waste society It means people throw away: Enough aluminum to rebuild the country’s entire commercial airline fleet every 3 months. Enough tires each year to encircle the planet almost 3 times. About 18 billion disposable diapers per year, which if linked end-to-end would reach to the moon and back 7 times. About 2 billion disposable razors, 10 million computers, and 8 million TV sets each year. About 2.5 million nonreturnable plastic bottles each hour Some 14 billion catalogs and 38 billion pieces of junk mail.

Hazardous waste: 

Hazardous waste Legally defined as any discarded solid or liquid material that: Contains one or more of 39 toxic, carcinogenic, mutagenic, or teratogenic compounds at levels that exceed established limits. Catches fire easily Is reactive or unstable enough to explode or release toxic fumes

Hazardous waste (cont.): 

Hazardous waste (cont.) Linguistic detoxification--ommissions from the list of hazardous materials. 94% of the country’s hazardous waste is not regulated by hazardous waste laws.

Producing less pollution: 

Producing less pollution Two ways to deal with the solid and hazardous waste: Waste management--views waste production as an unavoidable product of economic growth. Pollution prevention--views most solid and hazardous waste either as potential resources or harmful substances. Low-waste approach should have these goals: Reduce waste and pollution Reuse as many things as possible Recycle and compost as much waste as possible Chemically or biologically treat or incinerate waste that can be reduced, reused, or recycled Bury what is left in state of the art landfills

Reducing waste and pollution: 

Reducing waste and pollution Ways to reduce waste and pollution: Decrease consumption Redesign manufacturing processes and waste fewer resources when used Manufacturing processes can be redesigned to produce less waste and pollution Individuals can use less hazardous cleaning products Green design and life cycle assessment can help develop products that last longer and are easy to repair, reuse, manufacture, compost, or recycle. Eliminate wasteful packaging


Recycling Materials-recovery facilities--machines shred and automatically separate the mixed waste to recover glass, iron, aluminum, and other valuable resources. Recycling programs should not be judged on whether they pay for themselves any more than are conventional garbage disposal systems based on land burial or incineration. The major reasons for recycling are reduced use of virgin resources, reduced throughput of matter and energy resources, and reduced pollution and environmental degradation.

Detoxifying : 

Detoxifying Bioremediation--biological treatment of hazardous waste Phytoremediation--involves using natural or genetically engineered plants to remove contaminants Mass-burn incinerators--burn mixed trash without separating out hazardous materials All incinerators burning hazardous waste release toxic air pollutants

Land disposal: 

Land disposal Sanitary landfill--garbage graveyard in which solid wastes are spread out in thin layer, compacted,and covered daily. Leachate--rainwater contaminated as it percholates through the solid waste Deep-well disposal--liquid hazardous wastes are pumped under pressure through a pipe into dry, porous geologic formations

Lead, dioxins, and chlorine: 

Lead, dioxins, and chlorine Ways to protect children from lead poisoning: Test all children for lead by age 1 Ban incineration of solid and hazardous waste or greatly increasing current pollution control standards for old and new incinerators Phasing out leaded gasoline worldwide over the next decade Testing older housing and buildings for leaded paint and lead dust and removing this hazard Banning all lead solder in plumbing pipes and fixtures and in food cans Removing lead from municipal drinking water systems within 10 years Washing fresh fruits and vegetables and hands thoroughly Testing ceramicware used to serve food for lead glazing Reevaluate the proposed increase in electric cars propelled by lead batteries

Solutions: Achieving a low-waste society: 

Solutions: Achieving a low-waste society Don’t compromise our children’s futures by cutting deals with polluters and regulators Don’t be bulldozed by scientific and risk analysis experts Hold polluters-and elected officials who go along with them-personally accountable because what they are doing is wrong Don’t fall for the argument that protestors against hazardous-waste landfills, incinerators, and injection wells are holding up progress dealing with hazardous wastes

Solutions: Achieving a low-waste society: 

Solutions: Achieving a low-waste society Oppose all hazardous-waste landfills, deep-disposal wells, and incinerators Recognize that there is no such thing as safe disposal of a toxic or hazardous waste Pressure elected officials to pass legislation requiring that unwanted industries and waste facilities be distributed more widely instead of being so concentrated in poor and working class neighborhoods, many populated mostly by minorities Ban all hazardous-waste exports from one country to another


The End

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