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Rethinking Nuclear Power1. Introduction
• Energy units, uses, sources• Social benefits, demand
growth, conservation, developing world
• Periodic table, nuclear fission, nuclear power plants
Bob Hargraves, Hanover NH
The US has an energy crisis.
• Energy costs are high and rising.• Carbon emissions are high and rising.• We rely on oil from unstable countries.• Trade deficit grows 10¢/minute/car.• Farming fuel raises food prices.• Wind and hydro sites are limited.• Can nuclear power help?
$ $ $ $ $ $ $ $ $ $
US energy is 80% fossil sourced.
http://www.eia.doe.gov/bookshelf/brochures/aeo/aeobrochure2007.pdf
Electricity is 71% fossil sourced.
http://www.eia.doe.gov/cneaf/electricity/epa/epa_sum.html
US DOE projects energy growth.
http://www.eia.doe.gov/oiaf/aeo/execsummary.html
US DOE projects CO2 growth.
http://www.eia.doe.gov/oiaf/aeo/execsummary.html
Rethinking Nuclear Power1. Introduction
• Energy units, uses, sources
Energy and power unitsConverting between unitsWorld energy demandEnergy sources
Bob Hargraves, Hanover NH
My electric energy costs $0.136 per kilowatt-hour.
Bob Hargraves National Grid bill
•Delivery Service—The service(s) rendered by the local utility that provides the electric service to your home or business.•Customer Charge—The cost of providing customer-related services such as metering, meter reading and billing. These fixed costs are unaffected by the actual amount of electricity you use. •Distribution Charge—The cost of delivering electricity from the beginning of the Company’s distribution system to your home or business. •Transmission Charge—The cost of delivering electricity from the generation company to the beginning of the Company's distribution system. •Stranded Cost Charge—The cost associated with recovering the financial commitments made by National Grid to supply power to consumers in a regulated environment. •System Benefits Charge—The cost of providing energy efficiency programs, low income programs, and other system benefits as required by the Public Utilities Commission. •Consumption Tax—A tax imposed by New Hampshire law.
These costs are added to the cost of generating electricity.
Prefixes denote triple powers of ten.One is of these or US Englishexawatt 1,000 petawatts 1018 watts quintillionpetawatt 1,000 terawatts 1015 watts quadrillionterawatt 1,000 gigawatts 1012 watts trilliongigawatt 1,000 megawatts 109 watts billionmegawatt 1,000 kilowatts 106watts millionkilowatt 1,000 watts 103 watts thousandwatt 1,000 milliwatts 100 wattmilliwatt 1,000 microwatts 10-3 watts thousandthmicrowatt 1,000 nanowatts 10-6 watts milllionthnanowatt 1,000 picowatts 10-9 watts billionthpicowatt 1,000 femtowatts 10-12 watts trillionth
BTU is a British Thermal Unit
One BTU is theenergy required to raise the temperature ofone pound of waterone degree Fahrenheit.
…approximately the energy of burning a wooden match.
Energy equivalentsOne = this many of these unitsBTU (British Thermal Unit) 0.252 kilo caloriesJoule 1 watt secondCalorie 1 kilo calorieBTU 1.415 HP secondBTU 1,055 JouleKWH (kilo watt hour) 3,419 BTUQuad quadrillion BTUQuad 33.5 Giga watt yearsEJ 0.948 QuadeV (electron volt) 1.60 x 10-19 JouleKilo watt 1.341 HP
Energy and power sourcesOne provides of these unitsBBL (42 gal) petroleum 6,000,000 BTUTherm (100 f3) natural gas 100,000 BTUTon coal 20,000,000 BTUPound wood 6,500 BTUTypical large power plant 1 gigawattC cell (alkaline) 10 watt hoursTon TNT 1 gigacalorieTon ice melted 288,000 BTU absorbed100 quad 1 US economy one yr1 gram uranium (4.5% U235) 515 KWH electric pwr
Energy examples range over 87 orders of magnitude.
Item Energy (J) Item Energy (J)
Creation of Universe 1068 Atlantic jetliner crossing 1012
Supernova explosion 1044 Burning cord of wood 1010
Yearly solar emissions 1034 Human daily diet 107
D-D fusion of oceans 1031 AA alkaline battery 103
Earth’s fossil fuels 1023 Lifting an apple 1 m 101
Yearly US sunshine 1023 Cricket chirp 10-3
US energy consumption 1020 Fission uranium nucleus 10-11
Fission 1 T of uranium 1017 Chem reaction per atom 10-18
1 GW power station yr 1016 Photon of light 10-19
How many watts of heat does a person on a 2000 Calorie per day diet produce?
=?
Express conversion factors as 1.
1 Calorie = 1 kilocalorie
1 BTU = 0.252 kilocalories
1 kilowatt-hour = 3419 BTU
1 day = 24 hours
hour
day
BTU
urkilowattho
ekilocalori
BTU
Calorie
ekilocalori
241
34191
252.01
1
Multiply by 1: Calories to kilocalories.
Calorie
caloriekilo
day
Calorie 12000
…and cross off like units in numerator and denominator, just as in algebra.
Multiply by 1: kilocalories to BTU.
caloriekilo
BTUcaloriekilo
day
Calorie
caloriekilo
day
Calorie
252.
12000
12000
Multiply by 1: BTU to kilo watt hours.
BTU
hourwattkiloBTU
day
caloriekilo
BTUcaloriekilo
day
Calorie
caloriekilo
day
Calorie
3419252.
12000
252.
12000
12000
Multiply by 1: hours to days.
hour
dayhourwattkilo
day
BTU
hourwattkiloBTU
day
caloriekilo
BTUcaloriekilo
day
Calorie
caloriekilo
day
Calorie
243419252.
112000
3419252.
12000
252.
12000
12000
Multiply by 1: kilowatts to watts.
watt
kilowatt
wattkilowatt
hour
dayhourwattkilo
day
BTU
hourwattkiloBTU
day
caloriekilo
BTUcaloriekilo
day
Calorie
caloriekilo
day
Calorie
97
1000
24
1
3419252.
112000
243419252.
112000
3419252.
12000
252.
12000
12000
Hot? Spaulding Auditorium audience would melt a ton of ice an hour.
hourAuditorium
iceton
BTU
iceton
watthour
BTU
Auditorium
person
person
watt
04.1
2880001000
341990097
How many Exxon-Valdez tanker loads would meet all US energy needs for one year?
• Hints:– Exxon-Valdez carries 1.48 million BBL oil– 1 BBL oil = 6 million BTU– US economy consumes 100 quads a year
You can multiply anything by 1!
bbl
zLoadExxonValdeBTU
bbl
quadBTU
61048.11
61061
15101
Multiply 100 quads by 1 x 1 x 1!
bbl
zLoadExxonValde
btu
bblquadbtuquad
61048.16106
1510100
Cross off like units.
bbl
zLoadExxonValde
btu
bblquadbtuquad
bbl
zLoadExxonValde
btu
bblquadbtuquad
61048.16106
1510100
61048.16106
1510100
Do the arithmetic…
zLoadExxonValde
zLoadExxonValde
zLoadExxonValde
zLoadExxonValde
bbl
zLoadExxonValde
btu
bblquadbtuquad
200,11
112.10
88.8110
48.16110
61048.16106
1510100
5
5
66152
Energy conversion efficiencies vary.Energy conversion Typical Efficiency Coal to electricity 33 %Electric power distribution 93Electric motor or generator 80-95Pumped hydro storage 70-85Lead acid storage battery 70-85Lithium hydride storage battery 65Gasoline engine 20-25Diesel engine 39Electricity to hydrogen by electrolysis 50Hydrogen to electricity by fuel cell 28
How many truckloads of wood fuel would meet NH monthly electric use?
How many truckloads of wood fuel would meet NH monthly electric use?
• We need to know…– How much electric power used– How much heat needed to make the power– How much heat comes from burning wood– How much wood on a truck
Get energy data from http://eia.doe.gov.
NH used 926 gigawatt hours in Sept 2007.
http://www.eia.doe.gov/cneaf/electricity/epm/table5_4_b.html
http://Wikipedia.org is an encyclopedia.
Burning wood releases 6,500 BTU/lb.
A log truck can carry 64,000 lbs.
Multiply power used by 1x1x1x1.
truckloadtruckloadtruckload
lbwood
truckload
BTU
lbwood
KWHthermal
BTU
cKWHelectri
KWHthermal
cKWHelectri
800,22100228.640006500
1034193926
64000
6500
3419
33.0
10926
66
6
NH electric power used in September 2007
Efficiency of conversion heat to electricity
Equivalence of BTU and KWH
Heat of combustion of wood
Pounds of wood on truck
Multiply power used by 1x1x1x1.
truckloadtruckloadtruckload
lbwood
truckload
BTU
lbwood
KWHthermal
BTU
cKWHelectri
KWHthermal
cKWHelectri
800,22100228.640006500
1034193926
64000
6500
3419
33.0
10926
66
6
NH electric power used in September 2007
Efficiency of conversion heat to electricity
Equivalence of BTU and KWH
Heat of combustion of wood
Pounds of wood on truck
Multiply power used by 1x1x1x1.
truckloadtruckloadtruckload
lbwood
truckload
BTU
lbwood
KWHthermal
BTU
cKWHelectri
KWHthermal
cKWHelectri
800,22100228.640006500
1034193926
64000
6500
3419
33.0
10926
66
6
NH electric power used in September 2007
Efficiency of conversion heat to electricity
Equivalence of BTU and KWH
Heat of combustion of wood
Pounds of wood on truck
Multiply power used by 1x1x1x1.
truckloadtruckloadtruckload
lbwood
truckload
BTU
lbwood
KWHthermal
BTU
cKWHelectri
KWHthermal
cKWHelectri
800,22100228.640006500
1034193926
64000
6500
3419
33.0
10926
66
6
NH electric power used in September 2007
Efficiency of conversion heat to electricity
Equivalence of BTU and KWH
Heat of combustion of wood
Pounds of wood on truck
Multiply power used by 1x1x1x1.
truckloadtruckloadtruckload
lbwood
truckload
BTU
lbwood
KWHthermal
BTU
cKWHelectri
KWHthermal
cKWHelectri
800,22100228.640006500
1034193926
64000
6500
3419
33.0
10926
66
6
NH electric power used in September 2007
Efficiency of conversion heat to electricity
Equivalence of BTU and KWH
Heat of combustion of wood
Pounds of wood on truck
…about 22,800 truckloads a month!
Homework: You can now do energy problems yourself!
• A compact fluorescent light bulb using 23 watts gives the same light as a 100 watt incandescent bulb.
• There are 106 million US households.• Assume 5 100 watt bulbs are replaced by 23 watt ones
in each household.• Assume they are all on from 5 pm to 11 pm.
Homework: You can now do energy problems yourself!
• A compact fluorescent light bulb using 23 watts gives the same light as a 100 watt incandescent bulb.
• There are 106 million US households.• Assume 5 100 watt bulbs are replaced by 23 watt ones in each
household.• Assume they are all on from 5 pm to 11 pm.
• What % of annual US electric power would be saved?• How many tons of coal a year might not be burned?• What's that percentage of US coal consumption?
How much forest harvesting acreage would replace Vermont Yankee?
• Vermont Yankee generates 600 MW.
• Assume annual sustainable harvesting of 1/2 cord per acre.
• 1 cord = 1.2 tons.• Green Mountain
National Forest is 400,000 acres.
http://bioenergy.ornl.gov/papers/misc/energy_conv.html http://www.fs.fed.us/ne/fia/states/vt/vthilite97.pdf
• Vermont has 4,629 thousand acres of forest.
Rethinking Nuclear Power1. Introduction
• Social benefits, demand growth, conservation, developing world
Bob Hargraves, Hanover NH
http://en.wikipedia.org/wiki/World_energy_resources_and_consumption
Oil is the largest world energy source.
The US consumed 99 quads in 2008.
Coal 24Nuclear 8Imports 32
Residential 22Commerc & Ind 50Transportation 28
http://www.eia.doe.gov/emeu/aer/diagram1.html
Lawrence Livermore flows account for losses.
https://publicaffairs.llnl.gov/news/energy/energy.html
Petrol supplies 4X the energy of US nuclear.
https://http://www.eia.doe.gov/aer/pecss_diagram.html
The world consumed 472 quads in 2006.
http://www.eia.doe.gov/oiaf/ieo/world.html
The non-OECD nations demand more energy.
http://www.eia.doe.gov/oiaf/ieo/graphic_data_highlights.html
Income is dependent on energy.
https://www.cia.gov/library/publications/the-world-factbook/rankorder/2042rank.html
GDPpercapita
Annual kWh per capita
Nations with populations over 10 million.
North Korea’s poverty ($1,800 GDP per person) is illustrated by its electric power.
http://www.globalsecurity.org/military/world/dprk/dprk-dark.htm
Japan
China
South Korea
Growth of energy and coal use will be strong in non-OECD* nations.
Non-OECD energy use World coal use
http://www.eia.doe.gov/oiaf/ieo/world.html
* OECD are 30 leading democratic economies.
Coal consumption will increase strongly in non-OECD nations.
http://www.eia.doe.gov/oiaf/ieo/excel/figure_5data.xls
Growing 1 kg of cow meat takes 1,000 days of feeding.
1000 days
50 days
1 kg
1 kg
1 kg
400 days
Growing meat is energy intensive.
http://www.nytimes.com/2008/01/27/weekinreview/27bittman.html
Raising 1 kg [2.2 lb] beef uses the same energy as a 100 watt bulb for 20 days.
World livestock production causes more GHG emissions than transportation.
Natural grazing would save 2/3 of the energy – the energy used for raising and transporting animal feed.
Growing pigs uses 40% of the beef energy, and chickens 5%.
US people eat 8 oz meat per day, 2x the recommended diet.
Per capita US consumption is 3x the rest of the world.
Reducing meat consumption 20% has the same effect as changing all cars from Camrays to Priuses.
http://en.wikipedia.org/wiki/Feed_conversion_rate
In sieges Orvietto residents ate pigeons.lay egg 10 dayshatch chick 18 dayseat pigeon 28 days
The US is reducing energy consumption.
http://www.eia.doe.gov/emeu/aer/pdf/pages/sec1_12.pdf
Consumption drops as prices rise.
http://www.eia.doe.gov/emeu/aer/pdf/pages/sec1_12.pdf
US energy efficiency is improving > 1%/year.
http://www.eia.doe.gov/emeu/aer/pdf/pages/sec1_12.pdf
US energy efficiency is improving > 1%/year.
http://www.pewclimate.org/global-warming-basics/facts_and_figures/fig18.cfm
US energy use per $GDP is mid-scale.
http://www.eia.doe.gov/emeu/international/energyconsumption.html
United States
Japan
World total
Europe
http://en.wikipedia.org/wiki/Energy_intensity
US energy use per $GDP is mid-scale.
http://http://www.eia.doe.gov/oiaf/environment/emissions/carbon/index.html
US CO2 emissions are dropping.
http://http://www.eia.doe.gov/oiaf/environment/emissions/carbon/index.html
Three causes are GDP, energy intensity, carbon intensity reductions.
Rethinking Nuclear Power1. Introduction
• Periodic table, nuclear fission, nuclear power plants
Bob Hargraves, Hanover NH
Periodic table of the elements at ptable.com.
http://www.privatehand.com/flash/elements.html
Hover over element for properties.
Click Isotope tab, then element to get isotopes, then hover for characteristics.
The Sun fuses hydrogen into helium, releasing energy.
p
p p
p
The high temperature of the sun can force 4 repulsively charged protons together…
http://umbra.nascom.nasa.gov/images/eit_19990209_0122_304.gif
The Sun fuses hydrogen into helium, releasing energy.
p
p p
p
The high temperature of the sun can force 4 repulsively charged protons together…
p
http://umbra.nascom.nasa.gov/images/eit_19990209_0122_304.gif
n
p n
e+
e+
…fusing them into helium: 2 protons and 2 neutrons.
The mass loss is the energy freed.Element Unit atomic weight Total atomic weightH (x4) 1.00794 4.03176He 4.002602 4.002602
-------------Mass loss 0.029158
• Each atomic unit is 931 MeV of energy. [E = mc2]• The He is stable. It is bound by the 931
x .0029158 = 27 MeV energy that was lost.• Per nucleon this is 27 / 4 = 6.8 MeV “binding
energy”
The Crab nebula was a supernova in 1054.
• A supernova is the collapse of a star.
• Within a few seconds, matter in the white dwarf undergoes nuclear fusion.
• Uranium and other heavy elements are created.
• Matter is ejected into space at 3% of light speed.
• The earth coalesced from such matter over 4 billion years ago.
http://en.wikipedia.org/wiki/Supernova
The binding energy of uranium is less than that of more stable elements.
http://en.wikipedia.org/wiki/Binding_energy
Uranium
Iron
A neutron can fission uranium into krypton and barium.
http://en.wikipedia.org/wiki/Nuclear_fission
Ejected neutrons can create a chain reaction.
Uranium fissioning into krypton and barium releases energy.
http://en.wikipedia.org/wiki/Nuclear_fission
Element Nucleons Nucleon binding energy
Element binding energy
92U235235 x 7.6 MeV 1786 MeV
Uranium fissioning into krypton and barium releases energy.
Element Nucleons Nucleon binding energy
Element binding energy
92U235235 x 7.6 MeV 1786 MeV
56Ba141141 x 8.3 1170
36Kr9292 x 8.5 +782
Uranium fissioning into krypton and barium releases energy.
http://en.wikipedia.org/wiki/Nuclear_fission
Element Nucleons Nucleon binding energy
Element binding energy
92U235235 x 7.6 MeV 1786 MeV
56Ba141141 x 8.3 1170
36Kr9292 x 8.5 +782
total after 1952less before -1786
= energy released 166 MeV166 MeV for one atom. How much for more?
Avogadro's Number is 6.02 x 1023.
6.02 x 1023 is the number of atoms in
1 gram of 1H1 hydrogen, or 235 grams of 92U235 uranium.
What is the potential energy of 235 grams of Uranium235?
• 166 MeV x 6.02 x 1023 [Avogadro’s number]
What is the potential energy of 235 grams of Uranium235?
• 166 MeV x 6.02 x 1023
GWH
GWH
WattHour
GWH
Sec
Hour
Joule
SecWatt
eV
Joule
MeV
eV
4.4
103600
6.102.6166
103600
106.110
919623
9
196
What is the potential energy of 235 grams of Uranium235?
• 166 MeV x 6.02 x 1023
GWH
GWH
WattHour
GWH
Sec
Hour
Joule
SecWatt
eV
Joule
MeV
eV
4.4
103600
6.102.6166
103600
106.110
919623
9
196
What is the potential energy of 235 grams of Uranium235?
• 166 MeV x 6.02 x 1023
GWH
GWH
WattHour
GWH
Sec
Hour
Joule
SecWatt
eV
Joule
MeV
eV
4.4
103600
6.102.6166
103600
106.110
919623
9
196
What is the potential energy of 235 grams of Uranium235?
• 166 MeV x 6.02 x 1023
GWH
GWH
WattHour
GWH
Sec
Hour
Joule
SecWatt
eV
Joule
MeV
eV
4.4
103600
6.102.6166
103600
106.110
919623
9
196
What is the potential energy of 235 grams of Uranium235?
• 166 MeV x 6.02 x 1023
GWH
GWH
WattHour
GWH
Sec
Hour
Joule
SecWatt
eV
Joule
MeV
eV
4.4
103600
6.102.6166
103600
106.110
919623
9
196
What is the potential energy of 235 grams of Uranium235?
• 166 MeV x 6.02 x 1023
GWH
GWH
WattHour
GWH
Sec
Hour
Joule
SecWatt
eV
Joule
MeV
eV
4.4
103600
6.102.6166
103600
106.110
919623
9
196
The potential energy of 235 grams of Uranium-235 is 4.4 gigawatt hours.
• The potential energy of 235 grams of U235 is 166 MeV times 6.02 x 1023 [Avogadro number]
GWH
GWH
WattHour
GWH
Sec
Hour
Joule
SecWatt
eV
Joule
MeV
eV
MeV
4.4
103600
6.102.6166
103600
106.110
1002.6166
919623
9
196
23
• This could run a big 1GW electric power plant for 4.4 hours! [excepting efficiencies]
Uranium fuel is typically enriched from 0.7% U235 to 3.5% U235.
Uranium Ore 0.7%
Fuel pellet (3.5%)
http://www.nrc.gov/reading-rm/basic-ref/teachers/01.pdf
Fuel is enriched to 3.5% U-235.
http://www.world-nuclear.org/how/enrichment.html
UF6, uranium hexafluoride gas, is a vehicle for both U-235 and U-238.
Evacuated tubes contain rotors1-2 m long and 15-20 cm wide.
Spinning at 60,000 rpm creates centrifugal force of one million Gs.
The slightly heavier U-238 increases in concentration near the outside.
The lighter U-235 concentrates inside.
Slightly U-235 enriched UF6 is passed to the next stage centrifuge.
(An older, more costly UF6 diffusion cascade process is being phased out.)
F6U-238
F6U-235
A pressurized water nuclear reactor has three water circuits.
http://www.nrc.gov/reading-rm/basic-ref/students/animated-pwr.html
A boiling water nuclear reactor like Vermont Yankee has two water circuits.
http://www.nrc.gov/reading-rm/basic-ref/students/animated-pwr.html
Rethinking Nuclear Power1. Introduction
• End
Bob Hargraves, Hanover NH