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Chapter 16
Nonrenewable Energy Resources
Energy resourcesEnergy resources
99% of energy used to heat the earth and all the buildings comes from the sun
The sun also creates renewable energy resources – wind, flowing water, biomass
99% of energy used to heat the earth and all the buildings comes from the sun
The sun also creates renewable energy resources – wind, flowing water, biomass
The restThe rest
The last 1% comes from fuel resources
Fossil fuels make up the vast majority
Petroleum, coal, and natural gas
A small portion also comes from nuclear sources
The last 1% comes from fuel resources
Fossil fuels make up the vast majority
Petroleum, coal, and natural gas
A small portion also comes from nuclear sources
Is it getting hot in here?Is it getting hot in here?
Which energy source has the highest net energy ratio for space heating?Passive solar, yes, just letting in sunlight
to warm a room is the most efficient
Which energy source has the highest net energy ratio for high-temperature industrial uses?
coal
Which energy source has the highest net energy ratio for space heating?Passive solar, yes, just letting in sunlight
to warm a room is the most efficient
Which energy source has the highest net energy ratio for high-temperature industrial uses?
coal
Beep, BeepBeep, Beep
The highest net energy ratio for transportationNatural gas
Unfortunately, current NG cars have limited driving ranges and limited fueling sites.
The highest net energy ratio for transportationNatural gas
Unfortunately, current NG cars have limited driving ranges and limited fueling sites.
Mined coal
Pipeline
Pump
Oil well
Gas well
Oil storage
CoalOil and Natural Gas Geothermal Energy
Hot waterstorage
Contourstrip mining
PipelineDrillingtower
Magma
Hot rock
Natural gasOil
Impervious rock
Water Water
Oil drillingplatformon legs
Floating oil drillingplatform
Valves
Undergroundcoal mine
Water is heatedand brought upas dry steam or
wet steam
Waterpenetratesdownthroughtherock
Area stripmining
Geothermalpower plant
Coal seam
Fig. 14.11, p. 332
What is this stuff?What is this stuff?
Petroleum is a gooey liquid consisting of primarily hydrocarbons
Also called crude oil (or just oil)Oil is widely used because it is cheap,
easily transported and has a high net energy yield
Through distillation we produce many products - asphalt, heating oil, diesel, gasoline, grease, wax, natural gas
Petroleum is a gooey liquid consisting of primarily hydrocarbons
Also called crude oil (or just oil)Oil is widely used because it is cheap,
easily transported and has a high net energy yield
Through distillation we produce many products - asphalt, heating oil, diesel, gasoline, grease, wax, natural gas
Shifts in energy usage worldwide
Shifts in energy usage worldwide
During the 20th century
Coal use dropped from 55 to 22%Oil increased from 2 to 30%Natural gas rose from 1 to 23%Nuclear rose from 0 to 6%Renewable (wood and water )
dropped from 42 to 19%
During the 20th century
Coal use dropped from 55 to 22%Oil increased from 2 to 30%Natural gas rose from 1 to 23%Nuclear rose from 0 to 6%Renewable (wood and water )
dropped from 42 to 19%
Way to go USWay to go US
The U.S. is the world’s largest energy consumer
We use 25% of the world’s energy (even though we only have 4.5% of the total population)
India with 17% of the population only uses 3% of the world’s commercial energy
91% of the U.S.’s energy in nonrenewable
The U.S. is the world’s largest energy consumer
We use 25% of the world’s energy (even though we only have 4.5% of the total population)
India with 17% of the population only uses 3% of the world’s commercial energy
91% of the U.S.’s energy in nonrenewable
EnergyEnergy
Net energy refers to the amount of useful energy minus the energy needed to find, extract, process, concentrate, and transport to the users
Nuclear energy has a low net energy ratio because it is expensive to extract and process uranium, convert it into a fuel, build and operate the plant, and dismantle and deal with radioactive plants and waste
Net energy refers to the amount of useful energy minus the energy needed to find, extract, process, concentrate, and transport to the users
Nuclear energy has a low net energy ratio because it is expensive to extract and process uranium, convert it into a fuel, build and operate the plant, and dismantle and deal with radioactive plants and waste
Oil, Oil everywhere and not a drop to drink
Oil, Oil everywhere and not a drop to drink
Extracted as crude oil or petroleum, a thick liquid consisting of hydrocarbons, and some sulfur, oxygen and nitrogen impurities
Produced from decayed plant and animal material over millions of years
Extracted as crude oil or petroleum, a thick liquid consisting of hydrocarbons, and some sulfur, oxygen and nitrogen impurities
Produced from decayed plant and animal material over millions of years
Oil continuedOil continued
Normally crude oil is not found in underground pools, but is spread out in the pores and cracks within rock deep beneath the ground
Primary recovery – drill a hole and pump out the light weight crude that fills the hole
Normally crude oil is not found in underground pools, but is spread out in the pores and cracks within rock deep beneath the ground
Primary recovery – drill a hole and pump out the light weight crude that fills the hole
Oil continuedOil continued
Secondary recovery – pumping water into the well to force oil out of the pores
The oil and water mixture is separated after pumping
Only about 35% of the oil is removed by primary and secondary recovery
Secondary recovery – pumping water into the well to force oil out of the pores
The oil and water mixture is separated after pumping
Only about 35% of the oil is removed by primary and secondary recovery
Oil continuedOil continued
Tertiary recovery – either a heated gas or a liquid detergent is pumped into the well to help remove more oil
Tertiary is expensive
Tertiary recovery – either a heated gas or a liquid detergent is pumped into the well to help remove more oil
Tertiary is expensive
Oil continuedOil continued
At the refinery oil is converted into petrochemicals and used as a resource to create industrial organic chemicals, pesticides, plastics, synthetic fibers, paints, medicines and more.
OPEC – organization of petroleum exporting countries control 67% of the worlds oil and maintain control over pricing
At the refinery oil is converted into petrochemicals and used as a resource to create industrial organic chemicals, pesticides, plastics, synthetic fibers, paints, medicines and more.
OPEC – organization of petroleum exporting countries control 67% of the worlds oil and maintain control over pricing
Ticket to RideTicket to Ride
Most oil in the US is used for transportationGasolineDieselLubricant oil and greaseSome as LNG
Most oil in the US is used for transportationGasolineDieselLubricant oil and greaseSome as LNG
Diesel oil
Asphalt
Greaseand wax
Naphtha
Heating oil
Aviation fuel
Gasoline
Gases
FurnaceFig. 14.16, p. 337
Heatedcrude oil
Low land use
Easily transportedwithin and between countries
High netenergy yield
Low cost (withhuge subsidies)
Ample supply for42–93 years
Advantages
Moderate waterpollution
Releases CO2 when burned
Air pollutionwhen burned
Artificially low price encourageswaste and discourages search for alternatives
Need to findsubstitute within50 years
Disadvantages
Fig. 14.21, p. 340
Oil continuedOil continued Oil shale is a fine grained sedimentary rock containing
solid combustible organic material (waxy hydrocarbons) called kerogen
Shale oil is made from heating oil shale
Tar sand contains bitumen (a high sulfur heavy oil) another combustible organic material
Both are more expensive than crude recovery because it requires more energy, land disruption, and are more difficult to extract, produce roughly the same oil but with lower net energy yield
Oil shale is a fine grained sedimentary rock containing solid combustible organic material (waxy hydrocarbons) called kerogen
Shale oil is made from heating oil shale
Tar sand contains bitumen (a high sulfur heavy oil) another combustible organic material
Both are more expensive than crude recovery because it requires more energy, land disruption, and are more difficult to extract, produce roughly the same oil but with lower net energy yield
Oh, CanadaOh, Canada
There is a lot of shale oil and tar sands in North America, particularly in Canada.
As the price of crude oil goes up, the value of this heavy oil also goes up and becomes economically profitable to extract.
Unfortunately, almost all vegetation above the reserves must be removed to obtain these resources, so the environmental cost is very high
There is a lot of shale oil and tar sands in North America, particularly in Canada.
As the price of crude oil goes up, the value of this heavy oil also goes up and becomes economically profitable to extract.
Unfortunately, almost all vegetation above the reserves must be removed to obtain these resources, so the environmental cost is very high
Domestic OilDomestic Oil
US extraction of oil has decreased since 1985, thus increasing our reliance on other countries
Switching to alternative fuels sources helps maintain our economic independence
US extraction of oil has decreased since 1985, thus increasing our reliance on other countries
Switching to alternative fuels sources helps maintain our economic independence
Advantages Disadvantages
Moderate existingsupplies
Large potentialsupplies
High costs
Low net energyyield
Large amount ofwater needed toprocess
Severe land disruption fromsurface mining
Water pollution from mining residues
Air pollution when burned
CO2 emissionswhen burned
Fig. 14.25, p. 342
Natural GasNatural Gas
Mostly CH4 methane with some ethane, propane and butane and small amounts of hydrogen sulfide (toxic)
LPG (liquefied petroleum gas) the propane and butane are removed from natural gas and stored under pressure
Mostly CH4 methane with some ethane, propane and butane and small amounts of hydrogen sulfide (toxic)
LPG (liquefied petroleum gas) the propane and butane are removed from natural gas and stored under pressure
How long will it last?How long will it last?
Natural gas should last about 125 years worldwide
About 75 years in the US
Overall about 200-300 years with rising prices, better technology, and more discoveries
Natural gas should last about 125 years worldwide
About 75 years in the US
Overall about 200-300 years with rising prices, better technology, and more discoveries
Advantages Disadvantages
Good fuel forfuel cells andgas turbines
Low land use
Easily transportedby pipeline
Moderate environ-mental impact
Lower CO2 emissions thanother fossil fuels
Less air pollutionthan otherfossil fuels
Low cost (withhuge subsidies)
High net energyyield
Ample supplies(125 years)
Sometimes burned off andwasted at wellsbecause of lowprice
Shipped acrossocean as highlyexplosive LNG
Methane(a greenhouse gas) can leakfrom pipelines
Releases CO2
when burned
Fig. 14.26, p. 342
The future of power plantsThe future of power plants
There is currently being developed a combined cycle natural gas electric power plant with 60% efficiency
This is much better than 32-40% efficiency of others (coal, oil, nuke)
What other reasons make it better?
There is currently being developed a combined cycle natural gas electric power plant with 60% efficiency
This is much better than 32-40% efficiency of others (coal, oil, nuke)
What other reasons make it better?
CoalCoal
Solid fuel of combustible carbon, most formed 285-360 million years ago
Peat – 1st, low heat contentLignite – 2nd, low heat and low sulfurBituminous Coal – 3rd, high heat and
abundant supply, high sulfurAnthracite – 4th, high heat, low sulfur,
limited supply
Solid fuel of combustible carbon, most formed 285-360 million years ago
Peat – 1st, low heat contentLignite – 2nd, low heat and low sulfurBituminous Coal – 3rd, high heat and
abundant supply, high sulfurAnthracite – 4th, high heat, low sulfur,
limited supply
Increasing moisture content
Increasing heat and carbon content
Peat(not a coal)
Lignite(brown coal)
Bituminous Coal(soft coal)
Anthracite(hard coal)
Heat
Pressure Pressure Pressure
Heat Heat
Partially decayedplant matter in swampsand bogs; low heatcontent
Low heat content;low sulfur content;limited supplies inmost areas
Extensively usedas a fuel becauseof its high heat contentand large supplies;normally has ahigh sulfur content
Highly desirable fuelbecause of its highheat content andlow sulfur content;supplies are limitedin most areas
Fig. 14.27, p. 344
Coal for energyCoal for energy
Coal provides about 22% of the commercial energy in the world
It is used to create 62% of the worlds electricity
75% of the worlds steelChina is the largest user followed by
USUS creates 52% of energy with coal
Coal provides about 22% of the commercial energy in the world
It is used to create 62% of the worlds electricity
75% of the worlds steelChina is the largest user followed by
USUS creates 52% of energy with coal
Advantages Disadvantages
Low cost (with huge subsidies)
High net energyyield
Ample supplies(225–900 years)
Releases radioactive particles and mercury into air
High CO2 emissionswhen burned
Severe threat tohuman health
High land use (including mining)
Severe land disturbance, air pollution, andwater pollution
Very high environmentalimpact
Fig. 14.28, p. 344
The cost of coalThe cost of coal
Land disturbance Air pollution (especially sulfur dioxide) Co2 emissions Water pollution
Electricity production (coal) is the second largest producer of toxic emissions
The most deadly emission is mercury
Land disturbance Air pollution (especially sulfur dioxide) Co2 emissions Water pollution
Electricity production (coal) is the second largest producer of toxic emissions
The most deadly emission is mercury
Wonderful coalWonderful coal
60,000 babies annually are born with brain damage due to mercury exposure, typically from pregnant mothers eating mercury in fish
Coal also releases more radioactive particles into the atmosphere than nuclear power plants
Also, acid rain and methane release
60,000 babies annually are born with brain damage due to mercury exposure, typically from pregnant mothers eating mercury in fish
Coal also releases more radioactive particles into the atmosphere than nuclear power plants
Also, acid rain and methane release
Coal in the USCoal in the US
Air pollutants kill thousands (estimates are from 60,000 – 200,000)
Cause at least 50,000 cases of respiratory disease
Cost several billion dollars in property damage
Air pollutants kill thousands (estimates are from 60,000 – 200,000)
Cause at least 50,000 cases of respiratory disease
Cost several billion dollars in property damage
The good newsThe good news
Fluidized bed combustion is reducing the amount of pollution
Hot air is blown under a mix of crushed limestone and coal while it is burnt
This removes most sulfur dioxide, reduces Nox and burns the coal more efficiently and cheaply
Fluidized bed combustion is reducing the amount of pollution
Hot air is blown under a mix of crushed limestone and coal while it is burnt
This removes most sulfur dioxide, reduces Nox and burns the coal more efficiently and cheaply
Calcium sulfateand ash
Air
Air nozzles
Water
Fluidized bed
Steam
Flue gases
Coal Limestone
Fig. 14.29, p. 345
Coal gasificationCoal gasification
Solid coal can be converted into synthetic natural gas (SNG)
It can also be made into synfuels (liquids) through coal liquefaction
Neither is expected to play a major role in our future energy needs
Solid coal can be converted into synthetic natural gas (SNG)
It can also be made into synfuels (liquids) through coal liquefaction
Neither is expected to play a major role in our future energy needs
Raw coal
Pulverizer
Air oroxygen
Steam
Pulverized coalSlag removal
Recycle unreactedcarbon (char)
Raw gases CleanMethane gas
Recoversulfur
Methane(natural gas)
2CCoal
+ O2 2CO
CO + 3H2 CH4 + H2O
Remove dust,tar, water, sulfur
Fig. 14.30, p. 345
Advantages Disadvantages
Large potentialsupply
Vehicle fuel
Low to moderatenet energy yield
Higher cost thancoal
High environmentalimpact
Increased surfacemining of coal
High water use
Higher CO2 emissions than coal
Fig. 14.31, p. 346
Nuclear EnergyNuclear Energy
Uranium 235 and plutonium 239 are split (nucleus) to release energy
The reaction rate is controlledThe energy heats water and turns it
to steamSteam spins turbines connected to
generators which create electricity
Uranium 235 and plutonium 239 are split (nucleus) to release energy
The reaction rate is controlledThe energy heats water and turns it
to steamSteam spins turbines connected to
generators which create electricity
LWR light water reactorsLWR light water reactors
All US reactors are of this type, so know it
All US reactors are of this type, so know it
Periodic removal
and storage ofradioactive wastes
and spent fuel assemblies
Periodic removaland storage of
radioactive liquid wastes
Pump
Steam
Small amounts of Radioactive gases
Water
Black
Turbine Generator
Waste heat Electrical power
Hot water output
Condenser
Cool water input
Pump
Pump Wasteheat
Useful energy25 to 30%
WasteheatWater source
(river, lake, ocean)
Heatexchanger
Containment shell
Uranium fuel input(reactor core)
Emergency coreCooling system
Controlrods
Moderator
Pressurevessel
Shielding
Coolantpassage
Fig. 14.32, p. 346
CoolantCoolant
Hot coolantHot coolant
Nuclear is out of favor (unless you ask Bush)Nuclear is out of favor (unless you ask Bush)
The US has not ordered a new nuclear facility since 1978, and 120 ordered since 1973 were cancelled
Most countries are phasing out nuclear plants or are not continuing to expand their programs, except China who is trying to move away from dependence on coal
The US has not ordered a new nuclear facility since 1978, and 120 ordered since 1973 were cancelled
Most countries are phasing out nuclear plants or are not continuing to expand their programs, except China who is trying to move away from dependence on coal
Why is nuclear not meeting expectations?
Why is nuclear not meeting expectations?
Multi-billion dollar cost of construction Strict govt. safety regulations High operating costs More malfunctions than expected Poor management Public concern after Chernobyl, and Three Mile
Island Investor concern about economic feasibility
Multi-billion dollar cost of construction Strict govt. safety regulations High operating costs More malfunctions than expected Poor management Public concern after Chernobyl, and Three Mile
Island Investor concern about economic feasibility
Low risk of accidents because of multiplesafety systems(except in 35 poorly designed and run reactors in former SovietUnion and Eastern Europe)
Moderate land use
Moderate landdisruption andwater pollution(without accidents)
Emits 1/6 asmuch CO2 as coal
Lowenvironmentalimpact (withoutaccidents)
Large fuelsupply
Spreads knowledge and technology for building nuclear weapons
No acceptable solution for long-term storage of radioactive wastes and decommissioning worn-out plants
Catastrophic accidents can happen (Chernobyl)
High environmental impact (with major accidents)
Low net energy yield
High cost (even with large subsidies)
Advantages Disadvantages
Fig. 14.35, p. 349
Coal
Ample supply
High net energyyield
Very high airpollution
High CO2emissions
65,000 to 200,000deaths per yearin U.S.
High land disruption fromsurface mining
High land use
Low cost (with huge subsidies)
Nuclear
Ample supplyof uranium
Low net energyyield
Low air pollution(mostly from fuelreprocessing)
Low CO2emissions(mostly from fuelreprocessing)
About 6,000deaths per year in U.S.
Much lower landdisruption fromsurface mining
Moderate land use
High cost (with huge subsidies)
Fig. 14.36, p. 349
ChernobylChernobyl
In the former Soviet Union, April 26, 1986 the reactor core went out of control and exploded sending a cloud of radioactive dust into the atmosphere
3,576 – 32,000 people died 400,000 forced to evacuate 62,000 square miles still contaminated More than 500,000 people exposed to high
level radiation Cost the govt. $385 billion
In the former Soviet Union, April 26, 1986 the reactor core went out of control and exploded sending a cloud of radioactive dust into the atmosphere
3,576 – 32,000 people died 400,000 forced to evacuate 62,000 square miles still contaminated More than 500,000 people exposed to high
level radiation Cost the govt. $385 billion
Three Mile IslandThree Mile Island
March 29, 1979 in Harrisburg, Penn.Coolant failed and core meltedRadioactive material escaped into air50,000 people evacuatedLuckily the radiation release was
believed to be too low to cause death or cancer
Cleanup has cost $1.2 billion so far
March 29, 1979 in Harrisburg, Penn.Coolant failed and core meltedRadioactive material escaped into air50,000 people evacuatedLuckily the radiation release was
believed to be too low to cause death or cancer
Cleanup has cost $1.2 billion so far
What do we do with the waste?
What do we do with the waste?
Low level radioactive waste must be stored for 100-500 years until it reaches a safe level (does not give off harmful ionizing radiation)
This was done by sealing the waste in steel drums and dumping it in the ocean
Today some countries (US) stores the waste at govt. run landfills, but no one wants to live anywhere near them
Low level radioactive waste must be stored for 100-500 years until it reaches a safe level (does not give off harmful ionizing radiation)
This was done by sealing the waste in steel drums and dumping it in the ocean
Today some countries (US) stores the waste at govt. run landfills, but no one wants to live anywhere near them
Waste container
Steel wall
Steel wall
Severalsteel drumsholding waste
Lead shielding
2 meters wide2–5 meters high
Fig. 14.38a, p. 351
Clay bottom
Up to 60deep trenchesdug into clay.
As many as 20flatbed trucksdeliver wastecontainers daily.
Barrels are stackedand surroundedwith sand. Coveringis mounded to aidrain runoff.
Fig. 14.38b, p. 351
And the bad stuff?And the bad stuff?
High level radioactive waste must be stored for 10,000 to 240,000 years until it reaches a safe level
Currently most is stored at the reactor site, sealed in drums, in pools of water
High level radioactive waste must be stored for 10,000 to 240,000 years until it reaches a safe level
Currently most is stored at the reactor site, sealed in drums, in pools of water
Proposed methods of disposal
Proposed methods of disposal
Bury deep underground – this is the leading strategy currently
Shoot it into space/Sun Bury it deep in the Antarctic ice sheet Dump it into descending subduction zones Bury in deep mud deposits on ocean floor Convert into less harmful isotopes (currently
we do not have the technology)
Bury deep underground – this is the leading strategy currently
Shoot it into space/Sun Bury it deep in the Antarctic ice sheet Dump it into descending subduction zones Bury in deep mud deposits on ocean floor Convert into less harmful isotopes (currently
we do not have the technology)
Fig.
14.39a, p. 352
Slide 52
Personnel elevator
Air shaft
Nuclear waste shaft
2,500 ft.(760 m)deep
Fig. 14.39b, p. 352
Slide 53
Storage Containers
Fuel rod
Primary canister
Overpack container sealed
Fig. 14.39c, p. 352
Radioactive contaminationRadioactive contamination
The EPA suggests that there are 45,000 sites in the US (20,000 belong to the DOE)
It is expected to cost over $230 billion over the next 75 years
More than 144 highly contaminated weapons construction sites will never be completely cleaned
The EPA suggests that there are 45,000 sites in the US (20,000 belong to the DOE)
It is expected to cost over $230 billion over the next 75 years
More than 144 highly contaminated weapons construction sites will never be completely cleaned