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Energy and the Environment HNRT 228 – A Recap Spring 2013 Prof. Geller 1

Concepts For Understanding Energy z. Work z. Potential Energy z. Kinetic Energy z. Conservation of Energy z. Types/Sources of Energy 2

Work is Force times distance z. Definition of work y“work is equal to the force that is exerted times the distance over which it is exerted” ywork in Joules = xforce in Newtons * distance in meters y. W = f * d 3

Question for Thought z. A spring clamp exerts a force on a stack of papers it is holding together. Is the spring clamp doing work on the papers? y. A y. B Yes No z. If the spring clamp does not cause the paper to move, it is not acting through a distance and no work is done. 4

Power - Work per unit time z. Power defined y“power is the amount of work done divided by the time it takes to do that work” ypower in Watts = work in Joules / time in seconds y. P = W / t 5

Question for Thought z. A k. Whr is y. A y. B y. C y. D a unit of work a unit of energy a unit of power More than one of the above is true. z A k. Whr is a unit of work, and since energy is the ability to do work, it is also a unit of energy. In terms of units, a watt is a joule per second, and an hour, as a second, is a unit of time. The time units cancel, leaving a unit of a joule, which can be used to measure either work or energy. 6

Kinetic Energy z. Definition y“Kinetic energy equals the mass of the moving object times the square of that object’s speed, times the constant 1/2. ” ykinetic energy in Joules = 0. 5 * mass in kilograms * speed in meters per second y. K. E. = 0. 5 * m * v 2 7

Question for Thought z. Does a person standing motionless in the aisle of a moving bus have kinetic energy? y. A y. B Yes No z Relative to the bus, the person has no kinetic energy because the person is at rest relative to the bus. Relative to the ground, however, the person does have kinetic energy because the person is moving with the same speed as the bus. 8

Potential Energy z. Definition y“gravitational potential energy of any object equals its weight times its height above the ground” ygravitational potential energy in Joules = mass in kilograms * acceleration due to gravity * height in meters y. P. E. = m * g * h 9

Question for Thought z. What happens to the kinetic energy of a falling book when the book hits the floor? y. A y. B y. C The kinetic energy is destroyed. The kinetic energy is converted to heat only. The kinetic energy is converted to heat and sound. 10

Mass as Energy z. Definition y“every object at rest contains potential energy equivalent to the product of its mass times the speed of light squared” yenergy in joules = mass in kilograms * speed of light in meters per second y. E = m * c 2 11

History of Energy Use z. Early civilizations used human muscle power as their primary energy source. y. Energy provided by burning wood enabled people to cook food, heat living areas, and develop primitive metallurgy. x. Dense, rapidly growing settlements outstripped wood production, thus new fuel sources had to be utilized. • 1890, coal replaced wood - primary energy source 12

Fossil Fuels z Carboniferous period, (286 -362 Mya) y large deposits of plants, animals, and microorganisms. y Led to the formation of fossil fuel deposits. 13

Industrial Revolution - 1875 z. Industrial Revolution - Machines replaced human and animal labor in the manufacture and transportation of goods. y. Steam engines converting heat energy into forward motion was central to this transformation. x. Countries or regions without large coal deposits were consequently left behind. 14

Industrial Revolution z. Prior to the Industrial Revolution, goods were manufactured on a small scale in private homes – master craftsman y. Expanding factories = larger labor pools, move to city • 200 years, energy consumption increased 8 X – Increased levels of air pollution. 15

i. Clicker Question z. Fossil fuels are derived from biological material produced y. A y. B y. C y. D y. E at the time of the industrial revolution about 300 million years ago about 1 billion years ago at the turn of the previous century 16

Changes in Energy Sources to 2000 17

i. Clicker Question z. At the turn of this century (2000) most energy was derived from y. A y. B y. C y. D y. E Coal Wood Natural Gas Oil Nuclear Power 18

Role of The Automobile z Growth of automobile industry led to roadway construction y Better roads - Higher speeds x. Higher speeds - Bigger faster cars = Bigger faster cars Better roads z Convenience of two-car families y Job growth in automobile-related industries y Major role in development of industrialized nations. z Cars altered people’s lifestyle y Greater Distance Travel x. Sprawling Cities • Suburbs x. Vacations 19

Growth in the Use of Natural Gas z. Initially, natural gas was burned as a waste product at oil wells. y Before 1940, accounted for less than 10% of energy consumption in United States. x. By 1970, accounted for about 30% of energy needs. x. In 2003 accounted for 25% of U. S. consumption. y. Primarily used for home heating and industrial purposes. 20

How is Energy Used? z. Industrialized nations use energy for: y. Residential / Commercial uses y. Industrial uses y. Transportation z. Less developed countries use most energy for residential purposes. y. Cooking and Heating z. Developing countries use much of their energy to develop industry. 21

US use of oil to 2002 22

i. Clicker Question z. Oil use in the U. S. has always risen since 1960. y. A y. B True False 23

How does the US compare to others in overall energy use through 2002? 24

Gasoline Taxes and Fuel Cost 25

i. Clicker Question z. Which of the following countries has the lowest gas taxes? y. A y. B y. C y. D y. E France Germany Spain Japan USA 26

The Importance of OPEC z. Oil Producing and Exporting Countries y. Twelve members y. Control over 78% of world’s estimated oil reserves. • 1, 000 billion barrels 27

Overview of Energy Production/Consumption 28

i. Clicker Question z. The United States imports more energy than it produces? y. A y. B True False 29

Energy Flow from Source to Use (USA 2008) Note Changes from 2003, page 17 of textbook 30

TYPES OF ENERGY and their Transformation Mechanical, Electromagnetic, Electrical, Chemical and Thermal 31

i. Clicker Time! Electrical energy is transported to your house through power lines. When you plug an electric fan to a power outlet, electrical energy is transformed into what type of energy? A B C D E Mechanical Electromagnetic Electrical Chemical Thermal 32

Energy come from Energy Resources, that are converted into energy that we can easily use. Electricity is the main form of energy that we use and can power or charge what we need energy for. 33

To generate electricity… 1. 2. 3. 4. 5. 6. You need an energy source, e. g. coal This is burnt to produce heat or steam The heat or steam then drives a turbine The turbine then can drive a generator The generator then produces electricity The electricity is then transported in cables to where it is needed 34

Energy Resources can be divided into 2 categories: 1. Non-Renewable Resources For example – coal, oil, gas, uranium or lignite Once used these resources CANNOT be used again 2. Renewable Resources For example – wind, water or solar These resources can be used over and over again 35

Non-Renewable Resources: COAL What is it? z Formed underground from decaying plant material How much left in the world? z About 200 years Advantages? z Plenty left z Mining is getting more efficient Disadvantages? z Pollution: CO 2 emissions (linked to global warming), SO 2 (linked to acid rain) z Heavy & bulky to transport 36

Non-Renewable Resources: OIL What is it? z Formed underground from decaying animal and plant material How much left in the world? z Estimates vary, but average about 40 years Advantages? z Quite easy to transport z Efficient in producing energy z Less pollution than coal Disadvantages? z Not much left z Pollution: air and danger of water pollution through spills 37

Non-Renewable Resources: NATURAL GAS What is it? z Formed underground from decaying animal and plant material How much left in the world? z Estimates vary from 60 -100 years Advantages? z Clean, least polluting of all non-renewables z Easy to transport Disadvantages? z Some air pollution z Danger of explosions 38

Non-Renewable Resources: NUCLEAR What is it? z Uses uranium, naturally found in some rocks How much left in the world? z Not known Advantages? z Not much waste and few CO 2 emissions released, as well as, few other greenhouse gases Disadvantages? z High cost to build and close down power stations. z Waste is radioactive. Problem with getting rid of waste safely 39

Why is the term, FOSSIL FUEL used for coal, oil, gas and lignite? A Because they all contain fossils. B Because they were once food sources for things that are now fossils. C Because they are derived from living matter of a previous geological age. D Because of their energy per unit of mass. E Because Prof. Geller said so. 40

Renewable Resources: WIND What is it? It the movement of air from high to low pressure How much left? Lots Advantages? No pollution Disadvantages? Winds change all the time, not predictable 41

Renewable Resources: SOLAR What is it? Energy from the sun How much left? Lots Advantages? No pollution, can be used in remote areas Disadvantages? Can be expensive, needs sunlight At night it doesn’t work 42

Renewable Resources: BIO-ENERGY What is it? Biomass and Biogas – z fermented animal or plant waste z vegetation from sustainable sources How much left? Lots Advantages? Good availability Disadvantages? Can be expensive to set up 43

Renewable Resources: HYDRO What is it? Movement of water drives a turbine How much left? Lots Advantages? No CO 2 emissions, can control flooding and provide a good water supply to an area Disadvantages? Large areas maybe flooded. Visual and water pollution 44

Renewable Resources: GEOTHERMAL What is it? Heat from the ground – often used to heat water How much left? Lots Advantages? No CO 2 emissions Disadvantages? Expensive and can only be used in certain parts of the world 45

Renewable Resources: WATER & TIDAL What is it? Movement of sea drives turbines How much left? Lots Advantages? Can produce a lot of electricity, no CO 2 emissions Disadvantages? Not many suitable sites 46

Energy Transfer lec E l ica tr Thermal Electrical Chemical Ele Sound (mechanical) Mechanical ct ric al Light (Electromagnetic) 47

Oil Exploration and Extraction z Oil is a fossil fuel y formed from the remains of plants and animals x died in ancient seas around 300 million years ago z Biota such as plankton fall to the bottom of the sea and decay y form sedimentary layers y little or no oxygen present x microorganisms break down the remains into carbon-rich compounds y organic material mixes with the sediments to form fine-grained shale, or source rock y sedimentary rocks layer generate heat and pressure x distilled organic material forms crude oil and natural gas y oil flows from the source rock and accumulates in thicker, more porous limestone or sandstone known as reservoir rock. z When the Earth’s crust moves, the oil and natural gas is trapped in reservoir rocks, which are between layers of impermeable rock (cap rock– usually granite or marble) http: //www. energyquest. ca. gov/story/chapter 08. html 48

i. Clicker Question z. Oxygen is required in the formation of oil in the sedimentary layers y. A y. B True False 49

The Search for Oil z Oil companies usually contract out the search for oil to exploration geophysicists z Exploration geophysicists utilize surface features surface rock reservoir rock entrapment satellite images gravity meters magnetometers hydrocarbon sniffers sometimes called electronic noses y seismometers [most common technique used] y y y y http: //science. howstuffworks. com/oil-drilling 2. htm x shock waves developed x reflections interpreted z Oil exploration methods are still only about 10 percent successful in producing useful well http: //science. howstuffworks. com/oil-drilling 1. htm 50

i. Clicker Question z. What is the name of a scientist who explores for oil? y. A y. B y. C oil geologist exploration geophysicist petroleum physicist 51

Setting Up the Rig Once the land is ready, several holes are dug to make way for the rig and main hole. A rectangular pit, called a cellar, is dug around the location of the actual drilling hole. The cellar provides a workspace around the hole. The crew then drills a main hole. The following diagram shows how a rig is set. http: //science. howstuffworks. com/oil-drilling 2. htm 52

Crude oil to Refineries z Oil fields and offshore oil rigs generally have hundreds of wells with flow lines that carry crude oil to the lease tanks. The crude oil flows from the wells to the unseen lease tanks via the flow lines, where it is accumulated, sampled and measured prior to further transportation via other connecting pipelines. Oil pipelines are considered to be a closed system since the chemicals theoretically don’t touch the environment, however leaks in the system do occur. Also, oil tankers bring oil to refineries and as was the case in the Exxon Valdez disaster, the environment suffers Photo Courtesy http: //response. restoration. noaa. gov/photos/exxon. html tremendously from oil production. 53

Environmental Disasters Statistic courtesy of http: //www. itopf. com/stats. html 54

i. Clicker Question z. The process by which components in a chemical mixture are separated according to their different boiling points, is called y. A y. B y. C y. D y. E Distillationism Fractionation Fractioning Fractional distillation Fractional fractionating 55

i. Clicker Question z. Which of the following are not petroleum derived products? y. A y. B y. C y. D y. E gasoline kerosene jet fuel plastics None of the above 56

World Oil Consumption http: //people. hofstra. edu/geotrans/eng/ch 5 en 57

• Oil is trapped in rare geological structures • Most of the oil in the world comes from a few large wells • About one in ten exploratory drillings strike oil 58

Overview of Natural Gas z. Supply of recoverable natural gas available at affordable costs has greatly increased over past 10 years z. Industry’s ability to produce natural gas from shales has gone from almost 0 to > 20% of U. S. needs in just 10 years z. Natural gas demand is at 22 -23 Tcf/year in the U. S. (historic highs). Increased availability of gas will allow demand to continue to grow over next several years 59

U. S. Reserve Base – Trends Before and After Shale Gas Production Significant increase in gas reserves and production from shales starts in 1999 Source: EIA 60

U. S. Natural Gas Production +1. 1%/yr -1. 9%/yr +3. 7%/yr U. S. natural gas production is at its highest level ever in 2008 Source: EIA 61

Offshore Gulf of Mexico in Steep Decline Production is down by almost 50% from 2001 -07 Source: EIA 62

Frac’d (Fracturing) Wells Shale is very hard, and it was virtually impossible to produce gas in commercial quantities from this formation until recent improvements were made in hydraulic fracturing technology and horizontal drilling, and there was an upturn in the natural gas price. 63

Conventional Well vs. Shale Gas Well Production Curves 64

Basins Where Additional Gas Will Be Produced From Shales Marcellus Woodford Barnett Haynesville Estimated Gas In-Place in these Shales is ~ 2000 Tcf 65

Today’s Relative Share of Energy Market by Fuel Biofuels 1% Renewables 8% Coal 23% Nuclear 8% Liquids 37% Gas 23% Source: EIA – Annual Energy Outlook 2009 66

U. S. Energy Demand by Fuel 120 - History Projections les Renewab Quadrillion Btu’s 100 80 - Biofuels Liquids 60 as Natural G 40 - Nuclear 20 0 - 1980 Source: EIA – Annual Energy Outlook 2009 Coal 1995 2005 2015 2030 67

Natural Gas Use by Sector in 2008 29% Electricity Generation 21% Residential Electricity generation from natural gas has grown at rate of 4%/year since 1990 14% Commercial 3% Transportation 33% Industrial Source: EIA – Annual Energy Outlook 2009 Industrial usage of natural gas has fallen at rate of 2%/year since 1998 68

Today’s Relative Share of Electricity Generation by Fuel Other Renewables 3% Hydro 6% Nuclear 20% Coal 49% Natural Gas 21% Source: EIA – Electric Power Monthly, April 2009 Oil 1% 69

Natural Gas Supply thru 2030 History 25 Projections - 20 Unconventional 15 10 Source: EIA – Annual Energy Outlook 2009 2025 - Net Imports 2015 0 Alaska 2005 5 1995 - Conventional 70

History: U. S. Natural Gas – Production & Consumption Source: EIA 71

Supply vs. Demand thru 2015 Available supply: Assume 1. 8% growth / year in production capacity (starting in 2010) and net imports at 3 Tcf/yr vs. 3. 3 -4. 0 Tcf/yr seen since ‘ 01 Demand (dashed curve): Assume 4% growth in use of gas for electricity generation after 1 year, 3% reduction in overall demand for 2009 72

Natural Gas is Cleaner Relative Level of NOx Emissions 120 100 80 60 40 20 0 Natural Gas Diesel Ethanol Blends Low Sulfur Diesel Bio Diesel Relative Level of Particulate Emissions Gasoline 120 100 80 60 40 20 0 Source: South Coast Air Quality Management District 2007 Air Quality Management Plan Summit Panel 73

Natural Gas is a Low Carbon Fuel Natural Gas Oil 28% more Coal 0 50000 43% more 100000 150000 200000 Pounds of Carbon per Billion BTU Source: EIA, Natural Gas: Issues & Trends, 1998 74

Economics of fuels \$/KWh Source: SDI research + team analysis 75

Distribution of natural gas z Impractical to ship: must route by pipe z 1. 3 million miles of pipe (250, 000 miles of mains) 76

How much do we have left? z Estimated recoverable amount: 871 tcf z 40 years at current rate z Estimates like this do account for future discoveries y present proven reserves provide only 8 years’ worth 77

Recollecting Chemistry k. J per gram z All fossil fuels are essentially hydrocarbons, except coal, which is mostly just carbon z Natural Gas is composed of the lighter hydrocarbons (methane through pentane) z Gasoline is hexane (C 6) through C 12 z Lubricants are C 16 and up 55 48 48 51 50 46 48 48 78

Coal z Coal is a fuel that we have a lot of z Primarily carbon, but some volatiles (CO, CH 4) z Reaction is essentially C + O 2 CO 2 + energy z Energy content varies depending on quality of coal, ranging from 4– 7 Cal/g z Highly undesirable because of large amounts of ash, sulphur dioxide, arsenic, and other pollutants 79

Coal types and composition Natural Graphite Anthracite k. J/g fixed carbon 34 ash 29 Bituminous 35 Bituminous 31 subbituminous 27 Lignite 25 moisture content Peat Wood 21 volatile matter 20 80

Use of Coal z 88% of the coal used in the U. S. makes steam for electricity generation z 7. 7% is used for industry and transportation z 3. 5% used in steel production z 0. 6% used for residential and commercial purposes z 0. 1% used on Halloween for trick-or 81 treaters

Estimated Worldwide Coal Reserves Country Amount (109 tonne) Percentage of Total United States 250* 25 Russia 230† 23 Europe 138 14 China 115 12 Australia 82 8. 3 Africa 55 5. 6 South America 22 2. 2 North America 7. 7 0. 8 *1 st edition Total of book had U. S. at 1500 billion tons. What happened to all that coal? 984 100 † 1 st edition of book had Russian coal at 4300 billion tons. Gross overestimates? 82

U. S. Coal Production History 83

When will coal run out? z We use 109 tonnes of coal per year, so the U. S. supply alone could last as long as 250 (1500) years at current rate z Using variable rate model, more like 75– 100 (400– 600) years y especially relevant if oil, gas are gone z This assumes global warming doesn’t end up banning the use of coal z Environmental concerns over extraction also relevant 84

Shale Oil z Possibly 600– 2000 billion barrels of oil in U. S. shale deposits ycompare to total U. S. oil supply of 230 billion bbl z Economically viable portion may only be 80 billion bbl z 8 times less energy density than coal ylots of waste rock: large-scale disposal problem z Maximum rate of extraction may be only 5% of our current rate of oil consumption ylimited by water availability 85

Tar Sands z Sand impregnated with viscous tar-like sludge z Huge deposit in Alberta, Canada y 300 billion bbl possibly economically recoverable z It takes two tons of sands to create one barrel of oil y energy density similar to that of shale oil z In 2003, 1 million bbl/day produced y grand hopes for 5 Mbbl/day; or 6% of world oil production z 2002 production cost was \$20 per barrel, so economically competitive 86

i. Clicker Question z. Which of the following companies/agencies has Dr. Geller worked for in his life prior to GMU? y. A – General Sciences Corporation y. B – Science Applications Int’l Corporation y. C – Research Data Systems Corporation y. D – Federal Bureau of Investigation y. E – Defense Systems Inc. 87

i. Clicker Question z. Which of the following titles was a title that Dr. Geller held in his life prior to teaching at GMU? y. A – taxi driver y. B – truck driver y. C – priest y. D – program manager y. E – deputy director 88

Some Parting Thoughts z "Energy cannot be created or destroyed, it can only be changed from one form to another. " - Albert Einstein z "I'd put my money on the Sun and solar energy. What a source of power! I hope we don't have to wait until oil and coal run out before we tackle that. " - Thomas Edison z "Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning. " - Albert Einstein 89