Notes nonrenewable energy

Nonrenewable EnergyNonrenewable Energy Chapters 15Chapters 15

Living in the EnvironmentLiving in the Environment, 11, 11thth Edition, Miller Edition, Miller

Advanced Placement Environmental ScienceLa Canada High School

Dr. E

1. Energy Resources1. Energy Resources

2. Oil

3. Natural Gas

4. Coal

5. Nuclear Energy

www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

http://www.bio.miami.edu/beck/esc101/Chapter14&15.ppt

Energy SourcesEnergy SourcesModern society requires large quantities of energy that are generated from the earth’s natural resources.

Primary Energy Resources: The fossil fuels(oil, gas, and coal), nuclear energy, falling water, geothermal, and solar energy.

Secondary Energy Resources: Those sources which are derived from primary resources such as electricity, fuels from coal, (synthetic natural gas and synthetic gasoline), as well as alcohol fuels.

www.lander.edu/rlayland/Chem%20103/chap_12.ppt

http://www.lander.edu/rlayland/Chem%20103/chap_12.ppt

TO MAKE ELECTRICITY

Heat is needed to-

Boil the water to-

Make the steam to-

Turn the turbine to-

Generate the electrical energy

WE CALL ELECTRICITY!

ThermodynamicsThermodynamics

The laws of thermodynamics tell us two things about converting heat energy from steam to work:

1)1) The conversion of heat to work cannot be 100 % efficient because a portion of the heat is wasted.

2)2) The efficiency of converting heat to work increases as the heat temperature increases.



Energy Units and UseEnergy Units and Use

Btu (British thermal unit) - amount of energy required to raise the temperature of 1 lb of water by 1 ºF.

cal (calorie) - the amount of energy required to raise the temperature of 1 g of water by 1 ºC. Commonly, kilocalorie (kcal) is used.

1 Btu = 252 cal = 0.252 kcal

1 Btu = 1055 J (joule) = 1.055 kJ

1 cal = 4.184 Jwww.lander.edu/rlayland/Chem%20103/chap_12.ppt


Two other units that are often seen are the Two other units that are often seen are the horsepower and the watt. These are not units of horsepower and the watt. These are not units of energy, but are units of power.energy, but are units of power.

1 watt (W) = 3.412 Btu / hour1 watt (W) = 3.412 Btu / hour

1 horsepower (hp) = 746 W1 horsepower (hp) = 746 W

Watt-hour - Another unit of energy used only to Watt-hour - Another unit of energy used only to describe electrical energy. Usually we use describe electrical energy. Usually we use kilowatt-hour (kW-h) since it is larger.kilowatt-hour (kW-h) since it is larger.

Energy Units and UseEnergy Units and Use



Evaluating Energy ResourcesEvaluating Energy Resources

U.S. has 4.6% of world population; uses 24% of the world’s energy;

84% from nonrenewable fossil fuels (oil, coal, & natural gas);

7% from nuclear power;

9% from renewable sources (hydropower, geothermal, solar, biomass).

Changes in U.S. Energy UseChanges in U.S. Energy Use



Energy resources removed from the earth’s crust include: oil, natural gas, coal, and uranium



Fossil FuelsFossil Fuels

Fossil fuels originated from the decay of living organisms millions of years ago, and account for about 80% of the energy generated in the U.S.

The fossil fuels used in energy generation are:Natural gas, which is 70 - 80% methane (CH4)

Liquid hydrocarbons obtained from the distillation of petroleum

Coal - a solid mixture of large molecules with a H/C ratio of about 1



Problems with Fossil FuelsProblems with Fossil FuelsFossil fuels are nonrenewable resources

At projected consumption rates, natural gas and petroleum will be depleted before the end of the 21st century

Impurities in fossil fuels are a major source of pollution

Burning fossil fuels produce large amounts of CO2, which contributes to global warming



Petroleum products

Refined components of crude oil are used to manufacture many of the material goods we use every day.

1. Energy Resources

2. Oil2. Oil3. Natural Gas

4. Coal

5. Nuclear Energy



OilOilDeposits of crude oil often are trapped within the earth's crust and can be extracted by drilling a well

Fossil fuel, produced by the decomposition of deeply buried organic matter from plants & animals

Crude oil: complex liquid mixture of hydrocarbons, with small amounts of S, O, N impurities

Sources of OilSources of Oil•Organization of Petroleum Exporting Countries (OPEC) -- 13 countries have 67% world reserves:

• Algeria, Ecuador, Gabon, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, United Arab Emirates, & Venezuela

•Other important producers: Alaska, Siberia, & Mexico.



Oil in U.S.Oil in U.S.•2.3% of world reserves

•uses nearly 30% of world reserves

•65% for transportation

•increasing dependence on imports.



Low oil prices have stimulated economic growth, they have discouraged / prevented improvements in energy efficiency and alternative technologies favoring renewable resources.






• Burning any fossil fuel releases carbon dioxide into the atmosphere and thus promotes global warming.

• Comparison of CO2 emitted by fossil fuels and nuclear power.





Refining crude oilCrude oil from the ground is a messy mix of hundreds of hydrocarbons.

It is put through a refining process to segregate different components.

• Small-chain hydrocarbons boil at cooler temperatures in a distillation column, isolating lighter weight oils (e.g., butane).

• Long-chain hydrocarbons boil at hot temperatures, isolating heavier oils (e.g., lubricating oils).

1. Energy Resources

2. Oil

3. Natural Gas3. Natural Gas4. Coal

5. Nuclear Energy



Natural Gas - Fossil FuelNatural Gas - Fossil Fuel

• Mixture •50–90% Methane (CH4)

•Ethane (C2H6)

•Propane (C3H8)

•Butane (C4H10)

•Hydrogen sulfide (H2S)www.bio.miami.edu/beck/esc101/Chapter14&15.ppt


Sources of Natural GasSources of Natural Gas•Russia & Kazakhstan - almost 40% of world's supply.

•Iran (15%), Qatar (5%), Saudi Arabia (4%), Algeria (4%), United States (3%), Nigeria (3%), Venezuela (3%);

•90–95% of natural gas in U.S. domestic (~411,000 km = 255,000 miles of pipeline).





Natural GasNatural GasExperts predict increased use of natural gas during this century

Natural GasNatural GasWhen a natural gas field is tapped, propane and butane are liquefied and removed as liquefied petroleum gas (LPG)

The rest of the gas (mostly methane) is dried, cleaned, and pumped into pressurized pipelines for distribution

Liquefied natural gas (LNG) can be shipped in refrigerated tanker ships

http://www.kochhydrocarbon.com/

1. Energy Resources

2. Oil

3. Natural Gas

4. Coal4. Coal5. Nuclear Energy



Coal

Coal: compressed under high pressure to form dense carbon structures

First used 3,000 years ago

Powered the industrial revolution in England, then in other countries

Today is surpassed by oil, but is still the most abundant fossil fuel

Provides 1/4 of the world’s commercial energy consumption

How coal is formedSeveral types of coal exist, depending on the amount of heat and pressure that overlying sediments have exerted.

Ranks of CoalRanks of CoalLignite: A brownish-black coal of low quality (i.e., low heat content per unit) with high inherent moisture and volatile matter. Energy content is lower 4000 BTU/lb. Subbituminous: Black lignite, is dull black and generally contains 20 to 30 percent moisture Energy content is 8,300 BTU/lb. Bituminous: most common coal is dense and black (often with well-defined bands of bright and dull material). Its moisture content usually is less than 20 percent. Energy content about 10,500 Btu / lb.Anthracite :A hard, black lustrous coal, often referred to as hard coal, containing a high percentage of fixed carbon and a low percentage of volatile matter. Energy content of about 14,000 Btu/lb.

www.uvawise.edu/philosophy/Hist%20295/ Powerpoint%5CCoal.ppt

http://www.uvawise.edu/philosophy/Hist%20295/%20Powerpoint%5CCoal.ppt

http://www.fi.edu/guide/dukerich/%20coal.html

http://www.scsc.k12.ar.us/.../Members/%20Reynolds/Default.htm

PEATPEAT

LIGNITELIGNITE

garnero101.asu.edu/glg101/Lectures/L37.pptgarnero101.asu.edu/glg101/Lectures/L37.ppt

BITUMINOUSBITUMINOUS

ANTHRACITEANTHRACITE

garnero101.asu.edu/glg101/Lectures/L37.pptgarnero101.asu.edu/glg101/Lectures/L37.ppt

Main Coal DepositsMain Coal Deposits

BituminousBituminous

AnthraciteAnthracite

SubbituminousSubbituminous

LigniteLignite



Advantages and DisadvantagesAdvantages and Disadvantages

Pros•Most abundant fossil fuel•Major U.S. reserves•300 yrs. at current consumption rates•High net energy yield

Cons•Dirtiest fuel, highest carbon dioxide•Major environmental degradation•Major threat to health © Brooks/Cole Publishing Company / ITP


Mountaintop RemovalMachinery removes the tops of mountains to expose coal.

The resulting waste rock and dirt are dumped into the streams and valleys below.

Figure 15-14Figure 15-14

Environmental impactsMountaintop removal is every bit as drastic as it sounds.

This type of coal mining causes massive erosion, runoff, and habitat destruction.

garnero101.asu.edu/glg101/Lectures/L37.ppt

Sulfur in CoalSulfur in CoalWhen coal is burned, sulfur is released primarily as sulfur dioxide (SO2 - serious pollutant)

Coal Cleaning - Methods of removing sulfur from coal include cleaning, solvent refining, gasification, and liquefaction Scrubbers are used to trap SO2 when coal is burned

Two chief forms of sulfur is inorganic (FeS2 or CaSO4) and organic (Sulfur bound to Carbon)


Acid Mine Acid Mine DrainageDrainage

The impact of mine drainage on a

lake after receiving effluent

from an abandoned

tailings impoundment for

over 50 years

Relatively fresh tailings in an Relatively fresh tailings in an impoundment. impoundment.

The same tailings impoundment The same tailings impoundment after 7 years of sulfide after 7 years of sulfide

oxidation. The white spots in oxidation. The white spots in Figures A and B are gulls. Figures A and B are gulls.

http://www.earth.uwaterloo.ca/services/whaton/s06_amd.html

Mine effluent discharging from the bottom of a waste rock pile

Shoreline of a pond receiving AMD showing

massive accumulation of iron hydroxides

on the pond bottom

Environmental impacts

Compounds and particulate matter resulting from combustion of coal, oil, and gas:

Cause air pollution (from power plants, vehicle exhaust, etc.)

Drive climate change (from carbon dioxide emissions)

Throw the carbon cycle out of balance(transferring carbon stored underground to atmospheric carbon dioxide)

Environmental impacts

Water pollution also results from fossil fuel use:

Acid deposition (from sulfur pollutants emitted in power plant combustion)

Runoff from non-point sources (cars, homes)

Oil spills (not just large spills from tankers; mostly small spills from nonpoint sources)

Environmental impactsCoal mining has impacts:

• Habitat destruction from strip mining

• Erosion from strip mining

• Chemical runoff from strip mining through acid drainage

• Human health risks for workers from subsurface mining

Political, social, and economic impacts

The degree of dependence that our modern economies have on fossil fuels is risky.

This puts all our eggs in one basket.

Nations that supply oil can call the shots.

Nations that need oil are dependent on suppliers.

1. Energy Resources

2. Oil

3. Natural Gas

4. Coal

5. Nuclear Energy5. Nuclear Energy



Nuclear energy

Nuclear energy = energy that holds together protons and neutrons within the nucleus of an atom

We harness this energy by converting it to thermal energy, which can then be used to generate electricity.

Each conversion process involves transforming isotopes of one element into isotopes of other elements by the addition or loss of neutrons.

Nuclear energy: FissionNuclear fission = energy is released by splitting apart uranium nuclei by bombarding them with neutrons

This is the process used in nuclear reactors and weapons.

Nuclear energyComes from the radioactive element uraniumThe nuclear fuel cycle enriches forms of uranium to make it into usable fuel.Electricity is generated by controlling fission in nuclear reactors.

Nuclear reactorIn a reactor, fission boils steam to turn a turbine and generate electricity

Controlled Nuclear Fission ReactionControlled Nuclear Fission Reaction

cstl-cst.semo.edu/bornstein/BS105/ Energy%20Use%20-%203.ppt

Nuclear energy

Uranium is used for nuclear power because it is radioactive.

Radioisotopes emit subatomic particles and high-energy radiation as they decay.

Each radioisotope decays at a rate determined by that isotope’s half-life, the amount of time it takes for one-half of the atoms to give off radiation and decay.

The time needed for one-half of the nuclei in a radioisotope to decay and emit their radiation to form a different isotope

Half-time emitted Uranium 235 710 million yrs alpha, gammaPlutonium 239 24.000 yrs alpha, gamma

During operation, nuclear power plants produce radioactive wastes, including some that remain dangerous for tens of thousands of years

Half-LifeHalf-Life



Diagram of Radioactive Decay

cstl-cst.semo.edu/bornstein/BS105/ Energy%20Use%20-%203.ppt

• Genetic damages: from mutations that alter genes

• Genetic defects can become apparent in the next generation

• Somatic damages: to tissue, such as burns, miscarriages & cancers

Effects of RadiationEffects of Radiation



1. Low-level radiation (Gives of low amount of radiation)• Sources: nuclear power plants, hospitals &

universities• 1940 – 1970 most was dumped into the ocean• Today deposit into landfills

2. High-level radiation (Gives of large amount of radiation)• Fuel rods from nuclear power plants• Half-time of Plutonium 239 is 24000 years• No agreement about a safe method of storage

Radioactive WasteRadioactive Waste



Nuclear waste disposal

Nuclear waste must be disposed where it will not escape.


Nuclear waste is stored at 125 sites in 39 states.

Radioactive WasteRadioactive Waste1. Bury it deep underground.

• Problems: i.e. earthquake, groundwater…2. Shoot it into space or into the sun.

• Problems: costs, accident would affect large area.3. Bury it under the Antarctic ice sheet.

• Problems: long-term stability of ice is not known, global warming

4. Most likely plan for the US• Bury it into Yucca Mountain in desert of Nevada • Cost of over $ 50 billion• 160 miles from Las Vegas• Transportation across the country via train & truck




At Yucca Mountain, all nuclear waste in the U.S. would be buried in a network of tunnels deep underground.

Yucca Mountain

www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt

Nuclear troubles

Although nuclear power is clean, lacking the pollutants of fossil fuels, it has drawbacks:

• Its waste is dangerously radioactive.• Consequences of accidents can be catastrophic.

439 nuclear plants remain operating today in the world.



Three Mile IslandThree Mile Island•March 29, 1979, a reactor near Harrisburg, PA lost coolant water because of mechanical and human errors and suffered a partial meltdown

•50,000 people evacuated & another 50,000 fled area

•Unknown amounts of radioactive materials released

•Partial cleanup & damages cost $1.2 billion

•Released radiation increased cancer rates.



Nuclear accidents

The Three Mile Island accident caused a partial meltdown.

ChernobylChernobyl• April 26, 1986, reactor explosion (Ukraine) flung radioactive debris into atmosphere

• Health ministry reported 3,576 deaths

• Green Peace estimates 32,000 deaths

• About 400,000 people were forced to leave their homes

• ~160,000 sq km (62,00 sq mi) contaminated

• > Half million people exposed to dangerous levels of radioactivity

• Cost of incident > $358 billionwww.bio.miami.edu/beck/esc101/Chapter14&15.ppt


Nuclear accidents

The 1986 Chernobyl explosion caused the world’s most severe nuclear power plant accident.

Nuclear accidents

Fallout from Chernobyl was deposited across Europe.

Human Health Hazards

Radioactivity is dangerous to humans because the particles emitted damage DNA sequences and ultimately interrupt cell processes.

Radiation poisoning

Damage to gametes

Cancers

Tissue damage

Nuclear EnergyNuclear EnergyNuclear plants must be decommissioned after 15-40 yearsNew reactor designs are still proposedExperimental breeder nuclear fission reactors have proven too costly to build and operateAttempts to produce electricity by nuclear fusion have been unsuccessful

Phasing Out Nuclear PowerPhasing Out Nuclear Power•Multi-billion-$$ construction costs

•High operation costs

•Frequent malfunctions

•False assurances and cover–ups

•Overproduction of energy in some areas

•Poor management

•Lack of public acceptancewww.bio.miami.edu/beck/esc101/Chapter14&15.ppt
