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Energy Sources
• Geothermal• Solar• Nuclear
– Fission – splitting of heavy atoms to release energy. By-product of radiation with long half-life. This occurs at nuclear power plants.
– Fusion – joining of light atoms to produce energy. This occurs on the sun.
• Fossil fuels (natural gas, coal)• Wind• Hydroelectric
Air Conditioners
• SEER rating for air conditioners– BTU (British thermal unit)– Calorie
• V = I/R
• V = voltage; I = amps; R = resistance
• Energy star rating
Building Insulation
• R-value of insulation
• Building insulation materials– Good- Paper (cellulose)
• Least expensive; settles over time
– Better - Fiberglass • Blown-in or on rolls
– Best - Isocyanine• Expanding foam (sound proofing)
Nitrogen in Tires
• 147 buses run millions of miles per year.
• A ½ % savings in gas cost is a substantial savings.
• Tires wear more evenly and therefore tread life is longer.
• Less cost to replace tires, manufacture new tires and dispose of old tires.
Audit Questions• Findings of informal walk through/observations• No wrap on water heaters (2) -- question on audit• Frequency of cleaning/inspections• forced air boiler heaters –2• fans? -- audit question• how often change filters – audit• do we do low light day?• bathrooms -- no sensor on waters or auto-off• over 2000 amps in kitchen alone• 8 x 8 walk in refrigerator • 44 degrees water fountains• double pane windows• room settings controlled by computer; covered in rooms no tamper
Energy Sources in the United States
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 307
Wood Coal Petroleum / natural gas Hydro and nuclear
1850
100
80
60
40
20
0
Per
cent
9
91
1900
21
71
5 3
1940
10
50
40
1980
20
70
10
1990
26
58
16
Energy Sources in the United States
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 307
Wood Coal Petroleum / natural gas Hydro and nuclear
1850
100
80
60
40
20
0
Per
cent
9
91
1900
21
71
5 3
1940
10
50
40
1980
20
70
10
1990
26
58
16
2005
50
21 26
Energy Conversion
Timberlake, Chemistry 7th Edition, page 202
fanelectrical energy tomechanical energy
light bulbelectrical energy to
light energy tothermal and radiant energy
coffee makerelectrical energy to
thermal energy
pencil sharpenerelectrical energy tomechanical energy
Fission vs. Fusion
Fuse small atoms2H2 He
NO Radioactive
waste
Very HighTemperatures~5,000,000 oC
(SUN)
Split large atoms
U-235
Radioactive waste
(long half-life)
NuclearPowerPlants
Alike Different
Create Large Amounts
of EnergyE = mc2
Transmutationof Elements
Occurs
Change Nucleus
of Atoms
Fusion
Different
Topic Topic
Fission
Nuclear Fission
First stage: 1 fission Second stage: 2 fission Third stage: 4 fission
Tokamak Reactor
• Fusion reactor• 10,000,000 o Celcius• Russian for torroidial
(doughnut shaped) ring
• Magnetic field contains plasma
0 1 2 3 4Number of half-lives
Rad
iois
otop
e re
mai
ning
(%
)
100
50
25
12.5
Half-life of Radiation
Initial amountof radioisotope
t1/2
t1/2
t1/2
After 1 half-life
After 2 half-lives
After 3 half-lives
Reactor Core
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 622
Hot coolant
Control rods ofneutron-absorbingsubstance
Uranium in fuelcylinders
Incoming coolant
Copyright © 2006 Pearson Benjamin Cummings. All rights reserved.
Production of heat Production of electricity
Nuclear Power Plant
Nuclear Waste Disposal
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 626
Surfacedeposits
Host rockformation
Interbedrock layer
Aquifier
Aquifier
Interbedrock layer
Bedrock
River
Shaft
Repository
Wastepackage
Wasteform
0 1 2 3 4Number of half-lives
Rad
iois
otop
e re
mai
ning
(%
)
100
50
25
12.5
Half-life of Radiation
Initial amountof radioisotope
t1/2
t1/2
t1/2
After 1 half-life
After 2 half-lives
After 3 half-lives
Uranium Radioactive Decay
U-238
206
210
214
218
222
226
230
234
238
Ma
ss
nu
mb
er
81 82 83 84 85 86 87 88 89 90 91 92
Atomic number
Th-230
Th-234
Ra-226
Rn-222
Po-218
Pb-206
Pb-214
Pb-210
Pa-234
Bi-214
Po-214
Bi-210
Po-210
U-234
4.5 x 109 y24 d1.2 m2.5 x 105 y8.0 x 104 y1600 y3.8 d3.0 m27 m160 s5.0 d138 dstable
Nuclear Fusion
Sun
+ +
Fourhydrogen
nuclei(protons)
Two betaparticles
(electrons)
Oneheliumnucleus
He e2 H4 4
2
0
1-
1
1 + Energy
Conservation of Mass…mass is converted into energy
Hydrogen (H2) H = 1.008 amuHelium (He) He = 4.004 amu
FUSIONFUSION
2 H2 1 He + ENERGY
1.008 amux 44.0032 amu = 4.004 amu + 0.028 amu
This relationship was discovered by Albert EinsteinE = mcE = mc22
Energy= (mass) (speed of light)2
Nuclear Fusion
ray Gamma He H H 32
11
21
H2 He He He 11
42
32
32
Nuclear Fusion
Neutrino e H H H 01
21
11
11
(Positron)
Reporter:Reporter: This is “Sam”, your local reporter at Prairieland Elementary School. With the increases in energy costs and the awareness of global warming – this school has hired expert sleuths to find ways to conserve energy.With me are Professor Watt-son and his partner Sherlock Holmes.
Holmes:Holmes: Wattson and I have closely examined this building and have found several possible “energy hogs”.
Watt:Watt: I suspected the big energy hog would be found in the boiler room. This is the room where the water is heated and cooled. Heated to keep the school warm in the winter and cool during warm days. I noticed most of the pipes had proper insulation and the machines were regularly checked and maintained.
HVAC:HVAC: I am doing my best to keep you comfortable – I use four pipe heating and cooling. You could save up to 70% on your heating bills by switching to geothermal. I’m controlled by a computer system. I can be shut down to work in only certain areas of the building where people are at.
Holmes:Holmes: We’ll Wattson, HVAC is NOT our energy hog.
WattWatt: What did you find out about the electrical usage in this building for lighting?
LightingLighting: All lighting is very efficient fluorescent lighting. We could add additional switches to shut off some lights in the school when not in use. We may want to add motion detectors. Also, consider adding skylights in the gymnasium to save lighting with electricity. An added benefit would be we could open the skylights to cool the gym on hot days. Consider using larger windows to allow more natural light into the building.
Holmes:Holmes: I don’t think lighting is our energy hog either.
WattWatt: I noticed a very large portion of the energy bill was for electricity.
Electricity:Electricity: Much of the electrical equipment is energy star rated. We could switch computers from CRT monitors to more energy efficient flat screen monitors. It saves money by having all computers shut off and turned on automatically when school is not in session. Future equipment purchased should have a high energy star rating.
Holmes:Holmes: I don’t think electricity is our energy hog either.
WattWatt: Could we save money using solar energy? Holmes:Holmes: Yes, but we would need to sell that idea to the school board first.
Watt:Watt: Water conservation saves energy.
Water:Water: I don’t have to be chilled to 44oF in the fountains. Consider low flush toilets and sensors on the sinks in the bathrooms. Be sure all dripping faucets are repaired.
Holmes:Holmes: We’ll Wattson, water is NOT our energy hog and is being used very wisely.
WattWatt: Where else could we be losing energy?
WindowsWindows: I don’t hold in the heat as well as walls. I have two panes of glass that trap air and insulate. I could do more if you gave me reflective coating or low-E glass. The shades help some.
Holmes:Holmes: I don’t think windows is our energy hog either.
WattWatt: Do you think we’re losing energy out of the ceiling?
Insulation:Insulation: The water pipes are insulated. The ceiling insulation could be improved by adding isocyene insulation. It saves 30-50% energy over traditional cellulose are slightly better fiberglass insulation.
Holmes:Holmes: I don’t think insulation is our energy hog either.
WattWatt: Why does the school have a double set of doors? Doors:Doors: I stop the energy from leaving the school too quickly.
Reporter:Reporter: Overall, this school is energy efficient. It does many things right. Small improvements can be made in most areas. When new schools are built in this community, the knowledge we’ve learned in our audit can be used to make a better, more energy efficient school.
The public doesn’t understand the benefits of going green to save energy and help the environment.
Holmes - trench coat & microscopeWattson – Lab coatWater – gel in hair to look wet (blue shirt)Window – sunglassesInsulation – wrapped like a mummyLighting – lamp shade on head? / hand crank flashlight