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The Fukushima reactor situation Richard Wilson Mallinckrodt Professor of Physics (emeritus) Harvard University May 21st 2011. Cambridge March 2001. PUBLIC PERCEPTION DOMINATES NUCLEAR CONSTRUCTION COSTS.
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The Fukushima reactor situation Richard Wilson Mallinckrodt Professor of Physics (emeritus) Harvard University May 21st 2011 Cambridge March 2001
LARGE ACCIDENTS1948 DEFENSE IN DEPTH (multiple barriers)1976 formal analysis of events1979 TMI1986 Chernobyl 2011 Fukushima
UNDERSTANDING HISTORY“He who does not understand history is condemned to repeat it”What have we learned? And what will we learn from Fukushima? North Cambridge March 20th
Chronic Doeses and Long Term EffectsIf someone gets a dose just less than 200 Rems over a period of years then he or she has a 10%-20% addition to his cancer rate. This of course is about what one gets from cigarette smoking. NO INDIVIDUAL can be identified from the Chernobyl area who we know got his cancer from radiation. For low doses we calculate probabilisticallyWe should do this also for chemicals, air pollution etc.but do not always do so
Effect of accidental doses. What we knowRadiation dose of 300 Rems (3Sv) or more within a week leads to ACUTE RADIATION SICKNESS the body fails within weeks.At Chernobyl about 200 plant workers and firemen got this much and officially 31 died. (Perhaps another 30 in the army)No one in the general public got acute radiation sickness.This happened at no other nuclear power accident
The reactor statusAll operating reactors shut down when the eatrthquake came (Friday afternoon 11th March)No offsite power: but battery operated emergency systems and emergency diesels worked for 1 hour (maybe more) till Tsnami floode themThen water boiled away till after an hour or two the fuel was uncovered and heated upAt 1900 degrees Fahrenheit zirconium oxidizes leaving hydrogen behindBut a fundamental rule was forgotten
DECAY HEATKnown very well to a percent or two. roughly is enoughFULL POWER 500 Mw (electrical))1500 Mw (thermalOn shut down 8% of full power 120 Mw thermal drops to 1% after a day 10 Mw Thermaland 0.1% after a yearIf not removed or the fuel will melt and evaporateFUNDAMENTAL RULEAlways keep the fuel cool
WHY DID THEY DELAY PUTTING IN SEA WATER?IF THEY HAD PUT IN SEA WATER AT ONCE WE NEVER WOULD HAVE HEARD THE NAME!Salt water corrodes and the plant will never operate againSaturday morning was the last time to stop disasterAlso Why not do the same for the spent fuel pool?Monday morning was the last time
On Saturday 12th March the operators had no outside helpAll helicopters doing more important workno one to immediately reconnect electricityBy Thursday March 17thelectricity reonnected helicopters available.Water started cooling eveythingMy prediction (made first on March 12th):Few, maybe no one will get Acute Radiation Sickness. With no large cesium releases the number of CALCULATED cancers will be close to zero
THE MEDIA PANICKED ON WEDNESDAY. I DID NOT(1) The staff at the Fukushima power plant seem to have got over the initial shock and seem to be behaving well and even heroically(2) The decay heat that must be removed has gone down from 8% of full power to less than 1% although it is now dropping more slowly(3) The hydrogen explosions have been outside the reactor containments and have not stopped cooling the core(4) More helicopters are now available from a multitude of international sources to do what is necessary(5) Although it is hard to get precise information from the power plants (I do not have the telephone number of the control room as I had at TMI) the Japanese are hiding nothing and are asking for help.(6) There is a reliable report that electricity has been available since Thursday at the plant site(7) The pessimistic report of NRC Chairman Jazco to a US Senate committee on Wednesday was contradicted by the Japanese because he had his facts wrong.
Fatal cancers caused by arsenic in drinking water in Bangladesh 500,000Earthquake in Haiti 200,000Earthquake and Tsunami in Japan 20,000Fatal cancers from Chernobyl in next 60 years (calculated)4,000 in Belarus, Russia and Ukraine20,000 world wideFatal cancers from Natural Background in US6,000 per yearCancer fatalities from Three Mile Island 0cancers from Fukushima 0cancer increase from evacuation (1% or 1,400)
Major disasters500,000 Fatal cancers caused by arsenic in drinking water in Bangladesh from exposures already accumulated200,000 Earthquake in Haiti20,000 Earthquake and Tsunami in JapanFatal cancers from Chernobyl in next 60 years (calculated probabilistically)4,000 in Belarus, Russia and Ukraine20,000 world wide6,000/yr Cancers from Natural Background in US0 Cancer fatalities from Three Mile Island0 to 10 (My prediction) from Fukushima
Take an old reactor of outdated designShake it byan earthquake unknown for 3 centuriesExpose it to a Tsunami of a size not known beforeDiscionnect from outside powerYETthe number of radiation cancers is miniscule.This proves that reactors are safe.BUT THAT IS NOT THE WAY THEPUBLIC PERCEIVE ITSir Francis Graham-Smith, FormerAstronomer RoyalFormer Secretary of the Royal Society
What should we learn from this?Reinforce rule about keeping core coveredDiscourage transferring ALL the core to the spent fuel pool during maintenanceReconsider evacuation rules. Everyone forgot thatdislocation by evacuation has its own long term health effects maybe a 5% increase in background cancersNote that new reactors can use steam from a cooling pool to generate a little electricity
Thank you for your attentionMy notes on Fukushimahttp://physics.harvard.edu/~wilson/Japanese_reactors.html
????????????The early plants were TURNKEY. Construction costs generally have risen since 1970 We had good management and personnel in 1972 - now we don’tMandated retrofits after TMI????????? -North Cambridge MArch 20th
Over-regulation(Towers and Perrin 1995)Prescriptive not PerformanceDresden-II staff 250 (1975) -> 1,300+ (1997)unnecessary safety-grade equipment -North Cambridge MArch 20th
INCREASING FOSSIL FUEL1850 coal will run out in 30 years!1912 UK control of Anglo-Iranian1947 UK electricity rationing 1962 (King Hubbert) - 90% of oil discovered (in the USA)1978 (Vienna) UK Cabinet MinisterN. Sea oil < 1 million bbl/day(all gone in 20 years - today)yet: 1999 N. Sea 4 million bbl/day2011 Cracking underground rocksfor natural gas -North Cambridge MArch 20th
Is excessive regulation inevitable?YES: unless the utility industry fights in the courts as much as the antinukes.Is there hope?Chairman Jackson emphasized that this area is vitalAm I optimistic?NO!There is no proof that people are sensible -North Cambridge MArch 20th
ENVIRONMENTAL FACTORSforair pollutionglobal warming(Meeting Kyoto commitments) we do not need the breeder reactor. -North Cambridge MArch 20th
1998 construction cost$1,690 per MWe(GE reactor in Taiwan)four cents per kWheMUCH higher than $600/MWe -North Cambridge MArch 20th
The LONGER TERMIf promises are met for:safetyproliferation resistance costa fast neutron reactorwill be usefulfor waste disposalefficiencyYEAR 2100 + -North Cambridge MArch 20th
"Fermi's dream!”Benedict’s conclusion (1991)The expensive uranium would increase cost 50%Build a Breeder as soon as Possible! -North Cambridge MArch 20th
"Fermi's dream!”Breeder reactor U 238 -> Pu 239 (100 times as much energy per gram)High efficiency in fuel use Transuranic elements consumedWaste fission productsT1/2 < 30 years -North Cambridge MArch 20th
FAST NEUTRON REACTOR IMPROVEMENTSFuel burn up (metal fuel) was 1%NOW > 20%SAFERCheaperPyroprocessing possible(proliferation resistance)WHY DIDN’T THE COSTS COME DOWN? -North Cambridge MArch 20th
THE THORIUM CYCLE1959Indian Point designed to allow thorium Thorium reserves = 6 xUranium reserves -North Cambridge MArch 20th
The interpretation of theBenedict/OECD numbers has changedBusbar cost is now 5 c/kwhThe difference in costis negligible -North Cambridge MArch 20th
Only uranium 235 fissionable by slow neutronsOnly 3 suppliersJoachimstal, Czechoslovakia Union Minière, CongoEldorado mining Co, CanadaThe "nuclear age" was to be short lived! -North Cambridge MArch 20th
Fissionable elements: A = 4N - 1(Bohr and Wheeler)Plutonium 239 discovered(Seaborg, McMillan, Ramannod and Wahl)Uranium 233 and others discoveredMcMillan and Seaborg - Nobel prize "Fermi's dream!" -North Cambridge MArch 20th
Uranium SuppliesBenedict 1971Price Resource Cost Increase Total Electricity$/lb tons LWRBreeder generatedU3O8 mills/kWhe Gwe x yr LWRBreeder8 (base) 594,0000.00.03,470460,00010 940,0000.10.05,500720,000 15 1,450,000 0.40.08,4801,120,00030 2,240,0001.30.013,1001,720,00050 10,000,0002.50.058,3007,700,000100 25,000,0005.50.0146,00019,200,000 -North Cambridge MArch 20th
Why has the construction cost gone up?-demands by the public? Will public perception change?- Heat exchanger failures?(Auto radiatiors a few% of cost per KW)- increased real safety?(yet analysis is cheap)-increased regulation? -North Cambridge MArch 20th
Problemsincrease in construction cost(general)Public perception:proliferation problemsSafety -North Cambridge MArch 20th
1972 CONSTRUCTION COSTMaine Yankee $180 million$200 per MWeInflation Corr. $600 per MWhOPERATING COSTConnecticut Yankee <0.4 cents/kWhe Yankee Rowe <0.9 cents/kWheBenedict estimate 0.3 cents/kWhInflation corrected: 1 cent/kWhe -North Cambridge MArch 20th
EARLY OPTIMISMaboutLIQUID SODIUM REACTORSSeawolf Submarine worked(sometimes)Sodium not corrosive(except to human skin!)Higher temperature and efficiency -North Cambridge MArch 20th
LWRFUEL USE IMPROVEMENTS(1973) 20,000 MW days/ ton(1999) 40,000 MW days/ ton(fewer fuel outages)This SHOULD bring cost down -North Cambridge MArch 20th
GAS(1973) comes only with oil(1999) gas more plentifulEFFICIENCY(1999) Combined cycle X 2Less greenhouse gases Few particulates -North Cambridge MArch 20th
1984NAS(Energy Engineering Board)proposed acost studyOPPOSED by EPRIWHY? -North Cambridge MArch 20th