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Engineering 10. Chp.6 Future Challenges. Bruce Mayer, PE Licensed Electrical & Mechanical Engineer [email protected]. FIRST and SECOND Laws of THERMODYNAMICS. Class Question: Can Anyone Describe Either of the FIRST or SECOND Laws of ThermoDynamics ?. Laws of ThermoDyamics. - PowerPoint PPT Presentation
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[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt1
Bruce Mayer, PE Engineering-10: Intro to Engineering
Bruce Mayer, PELicensed Electrical & Mechanical Engineer
Engineering 10
Chp.6 Chp.6 FutureFuture
ChallengesChallenges
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt2
Bruce Mayer, PE Engineering-10: Intro to Engineering
FIRST and SECOND Laws ofFIRST and SECOND Laws ofTHERMODYNAMICS THERMODYNAMICS Class Question:
Can Anyone Describe Either of the Can Anyone Describe Either of the FIRST or SECOND Laws of FIRST or SECOND Laws of
ThermoDynamics? ThermoDynamics?
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt3
Bruce Mayer, PE Engineering-10: Intro to Engineering
Laws of ThermoDyamicsLaws of ThermoDyamics
In the Instructor’s Opinion The SECOND Law is the GREATEST of all the “Laws of Physics”
The ThermoDyamic Laws • Describe the Relationships & Connections
Between Work↔Heat↔Energy
• Describe and Quantify Reversibility and IRReversibilty
• Explains What’s “The Best we can Do”
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt4
Bruce Mayer, PE Engineering-10: Intro to Engineering
The “Laws” The “Laws” What are they? What are they?
First Law First Law of Thermodynamics• Energy can neither be CREATED nor
DESTROYED– But Energy Can be Moved, or Changed to
Other forms
Second Law Second Law of Thermodynamics• NATURALLY OCCURRING processes are
Directional– Natural process can go ONE WAY,
but NOT the OTHER
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt5
Bruce Mayer, PE Engineering-10: Intro to Engineering
ReversibilityReversibility
Reversibility is the ability to run a process back and forth (backwards and forwards) infinitely withOUT Losses
Money analogy: Currency Conversion• NO service fee (reversible):
$100 113000₩, and one hour later at the same place, 113000₩ $100
• WITH service fees (IRreversible: $100 68€, and one hour later at the same place, 68€ $90 (5% fee both ways)
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt6
Bruce Mayer, PE Engineering-10: Intro to Engineering
Reversibility and EnergyReversibility and Energy
Electric Current
Motor Generator
Voltage
Turbine Pump
Fluid Flow
Pressure
If IRreversibilities were ELIMINATED, these systems would run FOREVER.• These Systems would then be
Perpetual Motion Machines
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt7
Bruce Mayer, PE Engineering-10: Intro to Engineering
Example: Popping at BallonExample: Popping at Ballon
Not reversible unless energy is expended
X
A “reversible process” can go in either direction, but these processes are rare
Generally, the irreversibility shows up as waste heat
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt8
Bruce Mayer, PE Engineering-10: Intro to Engineering
Sources of IrreversibilitiesSources of Irreversibilities
Friction (force drops) Voltage drops Pressure drops Temperature drops Concentration drops Magnetic Hysteresis
(H Drops)
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt9
Bruce Mayer, PE Engineering-10: Intro to Engineering
First Law of ThermoDynamicsFirst Law of ThermoDynamics
One form of work may be converted into Another,
Or, work may be converted to heat, Or, heat may be converted to work, But, ALWAYS
FINAL energy = INITIAL energy
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt10
Bruce Mayer, PE Engineering-10: Intro to Engineering
10
22ndnd Law of Thermodynamics Law of Thermodynamics
We intuitively know that heat flows from higher to lower temperatures and NOT the other direction.• i.e., heat flows “DownHill”; just like water
WHY don’t see we Water flow UpHill, or Heat move Cold→Hot on Occasion?
Water and Heat Flow ONE-WAY Because These processes heat are inherently IRreversible.
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt11
Bruce Mayer, PE Engineering-10: Intro to Engineering
Heat↔Work ConverstionsHeat↔Work Converstions
Heat transfer is inherently irreversible. • This places LIMITS on the amount of work
that can be produced from heat.
Heat can be converted to work using heat engines; e.g.,• Jet engines (planes),
• Steam engines (electrical PowerPlants),
• Internal combustion engines (automobiles)
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt12
Bruce Mayer, PE Engineering-10: Intro to Engineering
Heat into Work (Power Plant)Heat into Work (Power Plant)
A heat engine takes in an amount of heat, Qhot, and produces work, W, and waste heat Qcold Qhot = W + Qcold
Nicolas Sadi Carnot (kar nō) derived the LIMITS of converting heat into work
High-temperatureSource, Thot
Low-temperatureSink, Tcold
HeatEngine
W
Qhot Qcold(e.g. flame) (e.g. cooling pond)
• W = Mechanical Work • Q = Heat
coldhot QWQ
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt13
Bruce Mayer, PE Engineering-10: Intro to Engineering
Carnot Equation: EfficiencyCarnot Equation: Efficiency
Given the heat ENGINE on the previous slide, the maximum work that can be produced is governed by:
hot
cold
hot
max
T
T
Q
W1
• where the temperatures are absolute (e.g. Kelvins)
Thus, as Thot Tcold, Wmax 0
This ratio is also called the Thermal Efficiency, η
N.L.S
. Carn
ot
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt14
Bruce Mayer, PE Engineering-10: Intro to Engineering
Example: PowerPlantExample: PowerPlant
A PowerPlant Boiler Runs at about 1000 °F
The “Heat Sink” is the cold Pacific Ocean at 52 °F
What is ηmax ?
1000 °F = 1460 °R
52 °F =
512 °R
%9.641460
51211max
hot
cold
T
T
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt15
Bruce Mayer, PE Engineering-10: Intro to Engineering
Moving Energy Cold→HotMoving Energy Cold→Hot
Not USING Heat, Just Moving it Around
Moving Heat UPhill requires WORK The CoEfficient of Performance, CoP,
informs about the effectiveness of AirConditioners and HeatPumps
High-temperatureSource, Thot
Low-temperatureSink, Tcold
HeatEngine
W
Qhot Qcold(e.g. OutSide Air) (e.g. InSide AC)
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt16
Bruce Mayer, PE Engineering-10: Intro to Engineering
Carnot Equation: CoPCarnot Equation: CoP
Given the heat PUMP on the previous slide, the Minimum Work needed to move heat UpHill is governed by: 1
1
coldhotmin
cold
TTW
Q
• where the temperatures are absolute (e.g. Kelvins)
Thus, as Thot Tcold, Wmin 0
This ratio is also called the CoEfficient of Performance, CoP
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt17
Bruce Mayer, PE Engineering-10: Intro to Engineering
Example: Air ConditionerExample: Air Conditioner
It’s REALLY Hot Outside, 105 °F
A “Cold Blooded” person Keeps the house at 65 °F
What is CoPmax?
105 °F = 565 °R
52 °F = 525 °R
1.131525565
1
1
1max
coldhot TTCoP
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt18
Bruce Mayer, PE Engineering-10: Intro to Engineering
Nicolas Léonard Sadi CarnotNicolas Léonard Sadi Carnot
Founder of the Science of ThermoDynamics
BORN: Paris, France,June 1 1796
DIED: Paris, France,August 24 1832)
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt19
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy & HumansEnergy & Humans
James Watt and His Predecessors (e.g., Savery & Newcomen) FREED Human Kind From Muscle Power
The Heat Engine Was One of the Great Advances in Human History• Enabled the “Industrial Age”
The Generation & Application of Energy Multiplies The Capabilities of EVERY Person
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt20
Bruce Mayer, PE Engineering-10: Intro to Engineering
Watt’s EngineWatt’s EngineWatt, James (1736-1819)
Scottish inventor and mechanical engineer, renowned for his improvements of the steam engine. Watt was born on January 19, 1736, in Greenock, Scotland. He worked as a mathematical-instrument maker from the age of 19 and soon became interested in improving the steam engines, invented by the English engineers Thomas Savery and Thomas Newcomen, which were used at the time to pump water from mines.
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt21
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy SourcesEnergy Sources
Let’s LIST Real And Potential Energy Sources OTHER Than Fossil Fuels
1. ?
2. ?
3. ?
4. ?
5. ?
6. ?
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt22
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fancy Fact & Fancy
Wind Power• Wind Turbines Are VERY Attractive
– Energy Input to Produce is Low
– Incremental Added Capacity
– NO Emissions of Any Kind
• Limitations– Low Energy Density
Must Cover Large Areas to Produce Much EnergyLimited Viable Sites
– Balance of System CostsNeed AC→AC Frequency Converter
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt23
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fancy Fact & Fancy
Split Wood, Not Atoms → BioMass• Burning Garbage or Plant Matter
is Attractive– Simultaneous Solution to Energy
and Solid-Waste Problems
– “Renewable” Resource
– Low Energy Input to Produce
• Limitation: Emission Stream is VERY Unpleasant– Scrubbing Wood-Smoke is MUCH Harder than
Cleaning Gasoline Combustion ByProducts
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt24
Bruce Mayer, PE Engineering-10: Intro to Engineering
Glen Canyon Dam – Page, AZGlen Canyon Dam – Page, AZ Electrical Power Generation
• River: Colorado River
• Plant Type: Conventional
• Powerhouse Type: Above Gnd
• Turbine Type: Francis
• Original Nameplate Capacity: 950,000 kW (950 MWe)
• Installed Capacity:1,304 MWe
• Year of Initial Operation:1964
• Net Generation (FY 2005): 3,208,591,407 kWh
• Rated Head:510 feet
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt25
Bruce Mayer, PE Engineering-10: Intro to Engineering
Glen
Can
yon
Dam
Glen
Can
yon
Dam
Aerial V
iewA
erial View
Generators
Tra
nsm
issi
on
To
wer
s
Transformer
Switch
Yard
Visito
r Cen
ter
Bridge
Lawn
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt26
Bruce Mayer, PE Engineering-10: Intro to Engineering
Glen Canyon Dam – Page, AZGlen Canyon Dam – Page, AZ
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt27
Bruce Mayer, PE Engineering-10: Intro to Engineering
Glen Canyon Dam – Power GenGlen Canyon Dam – Power Gen
150 rpm48
Poles
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt28
Bruce Mayer, PE Engineering-10: Intro to Engineering
Glen Canyon Dam – Power GenGlen Canyon Dam – Power Gen
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt29
Bruce Mayer, PE Engineering-10: Intro to Engineering
Glen Canyon Dam – Power GenGlen Canyon Dam – Power Gen
Set-UP Transformers
13.8kV 230kVor
13.8kV 345kV
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt30
Bruce Mayer, PE Engineering-10: Intro to Engineering
Fran
cis Tu
rbin
e F
rancis T
urb
ine
Gen
erator S
ystemG
enerato
r System
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt31
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fancy Fact & Fancy
Hydroelectric Power • Fancy: Can Provide for Future Growth
• Fact: Almost ALL Viable Hydro Sites Have Been USED– Damming More Rivers is a Political Issue
Ethanol as AutoMobile Fuel• Fancy: Ethanol Can Replace Oil As a
Source for Automobile Fuel
• Fact: Making Ethanol from Corn May Use MORE Energy than It Produces
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt32
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fancy Fact & Fancy
Ethanol Continued• DISTILLATION of Ethanol from Fermented
Corn Requires Large Amounts of Energy– Usually Provided by Burning Fossil Fuels at the
Distillation Site, or at the Electrical Power Plant
Solar PhotoVoltaics Can Supply Future Needs• Photovoltaic Solar-Electric Cells Have
Many Advantages– Remote Siting, Incremental Expansion
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt33
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fancy Fact & Fancy
Solar Cells Continued• BUT Making a Solar Cell Requires
Large Amounts of Energy– Silicon Cells are Made by, in the
Beginning, MELTING SAND
– Production Processes Can be Energy Intensive as Well
• Connecting to the Existing Electric Grid Includes a Great Deal of “Balance of System” Components– DC→AC “Inverters”, Battery Storage, etc.
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt34
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fancy Fact & Fancy
Solar Cells Continued• Solar Radiation has a
Very Low “Energy Density”– Requires LARGE Areas to Collect
Significant Amounts of EnergyCan Crowd-Out Other Uses:
Solar-Farm vs. Tomato-Farm
Hydrogen Fuel Cells• Based on Chemical Reaction
OHOH 2222
Proton Exchange
Membrane (PEM) FC
http://fuelcells.si.edu/
basics.htm
See also http://www.olympusmicro.com/primer/java/fuelcell/
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt35
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fancy Fact & Fancy
Hydrogen Fuel Cells Continued• The Fuel Cell Reaction Looks Very Good
– NO VOCs/HydroCarbon Emissions
– NO NOx emission
– NO Greenhouse Gases (CO2)
• But WHERE Do We Get the HYDROGEN?– There are NO Hydrogen WELLS or MINES
• The Viable Sources of Massive Amounts of Hydrogen themselves Require Large Energy or Carbon Inputs
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt36
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fact & FancyFancy In Apr04 Gov. Arnold Schwarzenegger
has proposed an ambitious network of hydrogen filling stations by 2010
See also http://www.hydrogenhighway.ca.gov/
But How can we MAKE all the Hydrogen needed to Replace Gasoline?
There are 3 Viable Alternatives
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt37
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fact & FancyFancy1. Use WIND or NUCLEAR Power to
generate Electricity which, in Turn, would be Used to Electrolize WATER
• Electrolosis applies Electrical current to water and splits it into oxygen and hydrogen, which are then separated…
• The Chemical Reaction
222 22 OHOH EnergyElectrical This is an EXTREMELY Energy Intensive Process
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt38
Bruce Mayer, PE Engineering-10: Intro to Engineering
Electric Cars: HElectric Cars: H22 vs ElectroChem vs ElectroChemUlf Bossel, “Does a Hydrogen Economy Make Sense?”, Proceedings
of the IEEE | Vol. 94, No. 10, October 2006, pp 1826-1837
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt39
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fact & FancyFancy2. Steam reforming of natural gas
• If you take methane, the main component of natural gas, and expose it to steam, the final products are primarily carbon dioxide and hydrogen. Chemically
• This is already a Large-Volume Industrial Process, but it produces a LOT of CO2 – a GreenHouse Gas
• Natural Gas Supplies are Limited
2224 42 COHOHCH
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt40
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fact & FancyFancy3. Coal gasification
• hydrogen could be produced at centralized plants, compressed and most likely transported in trucks.
• Coal is mostly carbon, but also contains hydrogen and sulfur. Exposed to water at high temperature and high pressure, it chemically reacts to yield carbon monoxide (CO) and hydrogen.
– But CO is Poisonous to Humans
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt41
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Sources Energy Sources Fact & Fact & FancyFancy3. Coal gasification, cont.
• Oxygen from additional water vapor turns carbon monoxide into carbon dioxide. So the end products are primarily carbon dioxide and hydrogen gas. Chemically
• We have LOTS of Coal, but still need to clean up the CO2 and H2S
SwHzCOyHOxHSCH 2222005080 ..
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt42
Bruce Mayer, PE Engineering-10: Intro to Engineering
48.13%
21.69%
19.54%
6.18%
1.34%
1.33%
1.12%
0.36%
0.28%
0.02%
0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50% 55%
Coal
NaturalGas
Nuclear
Hydro
Wind
Wood & BioMass
Fuel Oil
GeoThermal
Other
Solar
Fraction of Total Electrical Generation
Ele
ctr
ica
l Po
we
r So
urc
eUSA Electricity Production Mix - 2008
USA_Electricity_Mix_0810.xls
Total = 4 125 675GWhe
Source = USA Energy Information Adminsistration * http://www.eia.doe.gov/cneaf /electricity/epa/epates.html
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt43
Bruce Mayer, PE Engineering-10: Intro to Engineering
US
A P
rimary E
nerg
y U
SA
Prim
ary En
ergy
Pro
du
ction
by S
ou
rceP
rod
uctio
n b
y So
urce
http://www.eia.doe.gov/aer/overview.html * 2009
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt44
Bruce Mayer, PE Engineering-10: Intro to Engineering
USA Energy Production Mix - 2008
Coal, 32.36%
Natural Gas, 28.69%
Crude Oil, 14.27%
NGPL, 3.28%
Nuclear, 11.47%
Hydro, 3.33%
Geothermal, 0.49%
Solar/PV, 0.12%
Wind, 0.70%
BioMass, 5.29%
Energy Information Administration / Annual Energy Review 2008
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt45
Bruce Mayer, PE Engineering-10: Intro to Engineering
Energy Energy BackWork Ratio BackWork Ratio
The BIG QUESTION for Any Energy Src • For Every Unit of Energy OUTput, How Much
Energy was INput for the ENTIRE Production Stream?– In Electrical Power Generation, for the Steady-State
Condition, this is called the “BackWork Ratio”
Plant theofOutput Power
Plant Run the Power toBWR
Many Energy Sources Fail This Question• e.g., Many Solar-Electric Systems will NOT
Return the Energy Required to Make Them
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt46
Bruce Mayer, PE Engineering-10: Intro to Engineering
All Done for TodayAll Done for Today
California’sHydrogenHighWay
[email protected] • ENGR-10_Lec-09_Chp6_Population_Energy.ppt47
Bruce Mayer, PE Engineering-10: Intro to Engineering
A Potential Energy ScenarioA Potential Energy Scenario