Japan Nuclear Crisis 2011

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K J SOMAIYA INSTITUTE OF ENGG & IT

Japan Crisis

Tsunami to Nuclear Disaster

EVS Group No.

8/1/2011

Japan, one of the most developed countries has faced the wraith of nature. This report covers the

unfortunate events that happened on 11th March 2011 and its aftermath. Also it contains the series

of event that lead to a nuclear crisis. Future of Nuclear Energy and the need of alternatives to

nuclear energy are also detailed in this report.





Japan Crisis: Timeline of the Disaster,

From Tsunami to Nuclear Crisis

Friday March 11

At 0546 GMT (1446 in Japan) a massive earthquake, 8.9 on the Richter scale, unleashes ahuge tsunami which crashes through Japan's eastern coastline, sweeping buildings, boats, carsand people miles inland.

In Tokyo - hundreds of miles from the quake - large buildings shake violently and workersscramble into the streets for safety.

More than 50 aftershocks follow - seven at least 6.3 on the Richter scale, the size of the quakewhich struck New Zealand on February 22.

Sendai airport, north of Tokyo, is inundated with cars, trucks and buses and thick mud cover

its runways.

A large fire erupts at the Cosmo oil refinery in Ichihara city near Tokyo and burns out of control, with 100ft flames whipping into the sky.

Saturday March 12

Japan's government launches a massive rescue mission mobilising thousands of troops, 300 planes and 40 ships amid fears more than a thousand people have died.

US military vessels and aircraft carriers are sent, along with relief teams from Australia, NewZealand and South Korea.

Japan requests help from the UK.

There is an explosion at the Fukushima Dai-ichi nuclear plant.

Operators at the plant's Unit 1 detect eight times the normal radiation levels outside and 1,000times normal inside Unit 1's control room.

A team of UK search and rescue specialists and medics flies out.

Japan's government spokesman says the explosion that tore through the nuclear plant did notaffect the reactor.

The death toll rises to at least 1,300 dead but thousands more are missing - including 10,000from the coastal town of Minamisanriku.

More than 215,000 people are living in 1,350 temporary shelters in five prefectures, or states,the national police agency says.



More than one million households have no water. Four million buildings are without power.

Sunday March 13

Japan's nuclear safety agency says the cooling system of a third nuclear reactor at Fukushimahas failed - experts constantly monitor levels of radioactivity in the quarantined area.

The British embassy in Tokyo has a "long list" of people who are unaccounted for.

Around 170,000 people have been evacuated from a 12-mile radius around the Fukushimanumber one nuclear plant.

A government spokesman says the blast destroyed a building which housed a nuclear reactor, but the reactor escaped unscathed.

The Japanese government doubles the number of troops pressed into rescue and recoveryoperations to about 100,000.

Save The Children launches an appeal to raise £1 million for Japan's youngsters.

The Foreign Office receives more than 3,200 calls from concerned friends and relatives.

Prime minister Naoto Kan appeals to Japanese citizens to unite in overcoming what he says isthe country's worst crisis since the Second World War.

Nuclear plant operators try to keep temperatures down in a series of reactors.

Chief cabinet secretary Yukio Edano warns a hydrogen explosion could occur at Unit 3 of theFukushima Dai-ichi nuclear complex - the latest reactor to face a possible meltdown.

Mr Edano says the radiation released into the environment so far is so small it does not poseany health threats.

Japan's nuclear agency says up to 160 people were taken to hospital after possibly beingexposed to radiation while waiting to be evacuated.

It emerges around 17,000 British nationals were believed to be in Japan at the time of thequake.

Seismologists say the quake - one of the largest recorded - was actually 9.0 rather 8.9 on theRichter scale.

Monday March 14

A second hydrogen explosion is reported, this time at the unit 3 reactor at the Fukushima plant. Six people are injured.



The British Embassy in Tokyo is bolstered with extra staff flown in from across Asia,London and the Americas to help search hospitals for survivors in the worst-hit areas.

Japanese stocks nosedive as the huge cost of the disaster fuels fears about the country's

economy.

The Bank of Japan moves to stabilise markets by injecting a record 15 trillion yen (£114.4 billion) into money markets.

Fears of a major slowdown in the world's third-largest economy spark a huge slump inJapanese shares, with Tokyo's Nikkei 225 index closing more than 6% lower and some of the

world's biggest firms, such as Toshiba, Toyota and Honda, sustaining heavy share pricelosses.

Environmental campaigners call for a rethink of plans for new nuclear power stations in theUK.

Prime Minister David Cameron tells the Commons there are "severe concerns" for Britons

still missing four days after the devastating earthquake and tsunami.

Tuesday March 15

Dangerous levels of radiation leak from the Fukushima plant after a third explosion, believedto be in the number 2 reactor, and a fire, rock the complex.

In a televised statement after the blast, prime minister Kan urges those within 19 miles of thearea to stay indoors.



Japans Nuclear Reactors, Risk Assessment &

Accident Theory

It is somewhat obvious conclusion from the situation in Japan is that their risk assessment of

their nuclear reactors was deeply flawed. Risk is commonly defined as the probability of anaccident occurring times the expected loss. Another way to think about risk is as

probability times exposure.

In Japan, exposure is lessened because Japan is a developed country with resources torespond to a crisis. But exposure is heightened because of the dangers of widespreadradiation contamination, the duration of such contamination, and the proximity of the reactorsto population centres. Nuclear accidents are low-probability events, but exposure can becatastrophically high due to the dangers of a Chernobyl-like poisoning of the environment.And so even minimal probability events must be taken seriously.

This brings us to the probability of cooling system failure, the second element of the risk equation. David Lochbaum, a nuclear engineer with Union of Concerned Scientists, had thisto say about the probability of what we are now seeing in Japan:



The real situation they found themselves in is not really planned for. Those

plants are designed to be highly resistant to damage by earthquakes, and as

immune as possible to tsunami. The problem was the one -two punch. We

design against these sorts of things in isolation, and the combination is a

little beyond what they would have anticipated.

If Mr. Lochbaum is correct, this suggests a serious oversight on the part of risk planners for these nuclear plants. The combination of a tsunami and earthquake is hardlyan unforeseen possibility; that is why we have a tsunami warning system in the Pacific. But Iwould also argue that the ³cause´ of the reactor failures in Japan owe more to a failure indesigning independent safety systems than with any failure to imagine an earthquake-tsunamicombination.

Theories of accidents in large-scale systems typically argue that complex, tightly coupledsystems will produce interactions that can defeat safety devices. Furthermore, safety goalscan be compromised through a combination of bounded rationality and group interests, such

as profit pressures. In other words, small errors can propagate into large errors (tightcoupling) and errors can interact in unexpected ways (interactive complexity). Safety systemsmeant to decrease the probability of a serious accident can have the opposite effect if thesystems are interdependent. But creating truly independent or redundant safety systems haveeconomic resources.

The failure of cooling systems at three separate reactors at Fukushima may become a model

example for accident theory. THE below description highlights the interdependent nature of the system meant to protect the Fukushima plant from accidental meltdown:

The central problem arises from a series of failures that began after the tsunami. It easilyovercame the sea walls surrounding the Fukushima plant. It swamped the diesel generators,

which were placed in a low-lying area, apparently because of misplaced confidence that thesea walls would protect them. At 3:41 p.m. Friday, roughly an hour after the quake and justaround the time the region would have been struck by the giant waves, the generators shutdown. According to Tokyo Electric Power Company, the plant switched to an emergencycooling system that operates on batteries, but these were soon depleted.

There were multiple systems to power the cooling system: powerline, diesel generators and battery power. The tsunami/earthquake combination, however, took out both the

generators and the powerline. The generators depended on the sea walls. The batteries areshort-term; they depend on getting the powerlines or diesel back online quickly.

After the failure of the battery system, Tokyo Electric installed a mobile generator. Still,

³controlled containment venting´ was necessary, which suggests that the battery-controlledcooling mode was not designed for long-term use. This controlled venting failed, with aresulting explosion. (The NY Times suggests that the venting may have in fact set off theexplosion, which if true, illustrates the the complexity of this system.)

In another example of the complexity of this system, the high pressure inside the overheatedreactors was preventing efforts to inject cooling seawater into the reactor. A faulty valve had



stopped working, preventing the vents from releasing the radioactive steam. In turn, theincreased pressure prevented workers from injecting seawater into the reactor.

The Japanese nuclear crisis has taught us that these supposed redundant systems of failure for

the reactor are not necessarily redundant nor independent. And these types of nuclear reactors are complex, tightly coupled systems prone to the interactive, cascading failures

commonly described by accident theory.

One final note: besides redundancy, another way to prevent failure is the use of an

inherent fail-safe design. Pebble bed reactors are one such example. These reactors

contain spheres of uranium covered by a graphite material with hard shell. As the pebbles

heat up, they expand (the Doppler broadening effect). This expansion lessens the

likelihood of fission events, causing the temperature to naturally fall over time. When

designed properly, these reactors can power down safely without coolant or human

interaction. Germany, China and South Africa have all explored this technology at some

point, but China is the only one of the three with a current development program. The U.S.

DOE has also considered a similar design for its Next Generation Nuclear Plant .

Future of Nuclear Energy:

Nuclear Fusion

Nuclear Fusion is often proposed as the ultimate energy source. Great progress has beenmade in this field in the 50 years since it was first proposed. Construction has started for thenext generation Fusion Test Reactor (the ITER). Its projected start date is 2016. It will be

operated for the 10 years following to learn the about the Physics and Engineering required to build and operate a commercially competitive Power Plant. It is projected to produce 500MegaWatts of energy at full power. Like Nuclear Fission, the size of the resource (Deuteriumand Lithium) consumed in generating this energy is essentially unlimited. However muchresearch and development still needs to be done on the project. The proponents project theCapital Cost of a commercial plant, built in 2050, generating electricity via Nuclear Fusion to

be around $4000 per KW. Essentially the energy created by Nuclear Fusion is clean and

without any harmful by-products.

Alternative to Nuclear Energy

H ydrogen

Hydrogen is a completely clean fuel but it must be made from some other energy source. As afuel, Hydrogen has many benefits. It can be consumed in a Fuel Cell to make electricity veryefficiently and produces only water as emissions. Three kg of Hydrogen is expected to

provide a car a driving range of 400 km. The main difficulty with using hydrogen as a



transportation fuel is the ability to cheaply distribute and store it. However great progress is being made in this field. For example in January 2005, General Motors unveiled a concept

car with 5 kg of Hydrogen storage capacity and which provided a driving range of 500 km.

At present, the cheapest way to make Hydrogen is via chemical reactions on Natural Gas.There is already a substantial world-wide market for hydrogen gas. The main users of

Hydrogen are the Petroleum and Chemical Industries. The Petroleum industry uses Hydrogenin refineries and to upgrade Heavy Oil to Petroleum suitable for refining. This latter need isexpected to substantially increase the demand for Hydrogen as the production of Heavy Oilramps up.

Hydrogen can also be made from water via either electricity driven electrolysis or via hightemperature catalytic chemical reactions. There are extensive research programs to efficiently

produce Hydrogen using Solar, Wind and Nuclear Power.

Conclusions

The supporters of all the energy sources described here have answers to problems ascribed tothem. The fossil Fuel advocates are pursuing carbon sequestration projects. The Biomass,Solar and Wind Power advocates claim that costs will continue to diminish with the aid of government subsidies to ramp up production and to support continued research anddevelopment. The Nuclear Power industry advertise that their 3rd generation reactors will

provide electricity at less than half the cost of the average second generation reactor and be atleast 10 times safer. In addition they believe that there are now safe and reliable means todispose of waste over the long term. Further-more the industry claim that the FourthGeneration reactors will completely burn all the 238U in natural Uranium and/or fully utilizeThorium while generating one tenth to one hundred the waste of present reactors. If

perfected, there is sufficient accessible Uranium and Thorium to enable these reactors to

provide enough energy to power an advanced civilization for everyone living on Earth for well over 1 million years.

Of all the energy sources discussed here, Nuclear Fission Power is the lowest-cost form of non-greenhouse energy production. The second-generation reactors currently operating atWorld's best-practice level consistently produce low-cost electricity with no greenhouse gasemissions at high reliability. The French decision to go all-Nuclear has paid-off

handsomely and Sweden has the almost the lowest priced electricity in Europe.Furthermore, Denmarks' Greenhouse Gas emissions per capita are substantially greater than

both France and Sweden since the Danes use coal power for the majority of their electricityneeds even with their commitment to Wind Power.

In the the longer term advanced reactors, fusion-fission hybrids and accelerator driven systems that

efficiently use the World's abundant Thorium and Uranium reserves have the capability to power a

planet-wide advanced civilization essentially indefinitely. They also have the capability to generate

energy from and dispose of the long-lived transuranic waste.However Nuclear technology will

always require strict safe-guards and independent oversight.

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Japan Nuclear Crisis 2011