NUCLEAR POWER PLANT -APARNA.P

DONE BYAPARNA.PPRAYAGA.MENON VISMAYA

NUCLEAR POWER PLANT Nuclear power is the use of sustained nuclear fission to

generate heat and electricity. Nuclear power plants provide about 6% of the world's energy and 13–14% of the world's electricity with the U.S., France, and Japan together accounting for about 50% of nuclear generated electricity. In 2007, the IAEA reported there were 439 nuclear power reactors in operation in the world, operating in 31 countries.  Also, more than 150 naval vessels using nuclear propulsion have been built.

There is an ongoing debate about the use of nuclear energy . Proponents, such as the World Nuclear Association and IAEA, contend that nuclear power is a sustainable energy source that reduces carbon emissions. Opponents, such as Greenpeace International and NIRS, believe that nuclear power poses many threats to people and the environment.

Advantages Almost 0 emissions (very low greenhouse gas emissions).  They can be sited almost anywhere unlike oil which is mostly imported. The plants almost never experience problems if not from human error, which almost

never happens anyway because the plant only needs like 10 people to operate it.  A small amount of matter creates a large amount of energy. A lot of energy is generated from a single power plant. Current nuclear waste in the US is over 90% Uranium. If reprocessing were made legal

again in the US we would have enough nuclear material to last hundreds of years. A truckload of Uranium is equivalent in energy to 10,000+ truckloads of coal. (Assuming

the Uranium is fully utilized.) A nuclear aircraft carrier can circle the globe continuously for 30 years on its original fuel

while a diesel fueled carrier has a range of only about 3000 miles before having to refuel.

Modern reactors have two to ten times more efficiency than the old generation reactors currently in use around the US.

New reactor types have been designed to make it physically impossible to melt down. As the core gets hotter the reaction gets slower, hence a run-away reaction leading to a melt-down is not possible.

Theoretical reactors (traveling wave) are proposed to completely eliminate any long-lived nuclear waste created from the process.

Breeder reactors create more usable fuel than they use. Theoretical Thorium reactors have many of the benefits of Uranium reactors while

removing much of the risk for proliferation as it is impossible to get weapons-grade nuclear materials from Thorium. 

Disadvantages

Nuclear plants are more expensive to build and maintain.  Proliferation concerns - breeder reactors yield products that could potentially be stolen and turned into

an atomic weapon.  Waste products are dangerous and need to be carefully stored for long periods of time. The spent fuel is

highly radioactive and has to be carefully stored for many years or decades after use. This adds to the costs. There is presently no adequate safe long-term storage for radioactive and chemical waste produced from early reactors, such as those in Hanford, Washington, some of which will need to be safely sealed and stored for thousands of years. 

Early nuclear research and experimentation has created massive contamination problems that are still uncontained. Recently, for instance, underground contamination emanating from the Hanford Nuclear Reservation in Washington State in the U.S. was discovered and threatens to contaminate the Columbia River (the largest river in North America west of the continental divide). 

A lot of waste from early reactors was stored in containers meant for only a few decades, but is well past expiration and, resultingly, leaks are furthering contamination. 

Nuclear power plants can be dangerous to its surroundings and employees. It would cost a lot to clean in case of spillages.

There exist safety concerns if the plant is not operated correctly or conditions arise that were unforeseen when the plant was developed, as happened at the Fukushima plant in Japan; the core melted down following an earthquake and tsunami the plant was not designed to handle despite the world's strongest earthquake codes.

Many plants, including in the U.S., were designed with the assumption that "rare" events never actually occur, such as strong earthquakes on the east coast (the New Madrid quakes of the 1800s were much stronger than any east coast earthquake codes for nuclear reactors; a repeat of the New Madrid quakes would exceed the designed earthquake resiliency for nuclear reactors over a huge area due to how wide-spread rare but dangerous eastern North American earthquake effects spread), Atlantic tsunami (such as the 1755 Lisbon quake event, which sent significant tsunami that caused damage from Europe to the Caribbean) and strong hurricanes which could affect areas such as New York that are unaccustomed to them (rare, but possibly more likely with global warming)

Mishaps at nuclear plants can render hundreds of square miles of land uninhabitable and unsuitable for any use for years, decades or longer, and kill off entire river systems

Calder Hall nuclear power station in the United Kingdom was the world's first nuclear power station to produce electricity in commercial quantities.

On June 27, 1954, the USSR's Obninsk Nuclear Power Plant became the world's first nuclear power plant to generate electricity for a power grid, and produced around 5 megawatts of electric power

Life cycle

THE NUCLEAR FUEL CYCLE BEGINS WHEN URANIUM IS MINED, ENRICHED, AND MANUFACTURED INTO NUCLEAR FUEL, (1) WHICH IS DELIVERED TO A NUCLEAR POWER PLANT. AFTER USAGE IN THE POWER PLANT, THE SPENT FUEL IS DELIVERED TO A REPROCESSING PLANT (2) OR TO A FINAL REPOSITORY (3) FOR GEOLOGICAL DISPOSITION. IN REPROCESSING 95% OF SPENT FUEL CAN BE RECYCLED TO BE RETURNED TO USAGE IN A POWER PLANT (4).

High-level radioactive waste

The world's nuclear fleet creates about 10,000 metric tons of high-level spent nuclear fuel each year. High-level radioactive waste management concerns management and disposal of highly radioactive materials created during production of nuclear power. The technical issues in accomplishing this are daunting, due to the extremely long periods radioactive wastes remain deadly to living organisms. Of particular concern are two long-lived fission products, Technetium-99 (half-life 220,000 years) and Iodine-129 (half-life 15.7 million years), which dominate spent nuclear fuel radioactivity after a few thousand years. The most troublesome transuranic elements in spent fuel are Neptunium-237 (half-life two million years) and Plutonium-239 (half-life 24,000 years).Consequently, high-level radioactive waste requires sophisticated treatment and management to successfully isolate it from the biosphere. This usually necessitates treatment, followed by a long-term management strategy involving permanent storage, disposal or transformation of the waste into a non-toxic form.

Solid waste

The most important waste stream from nuclear power plants is spent nuclear fuel. It is primarily composed of unconverted uranium as well as significant quantities of transuranic actinides (plutonium and curium, mostly). In addition, about 3% of it is fission products from nuclear reactions. The actinides (uranium, plutonium, and curium) are responsible for the bulk of the long-term radioactivity, whereas the fission products are responsible for the bulk of the short-term radioactivity.

Spent nuclear fuel stored underwater and uncapped at the Hanford site inWashington, USA.

Economics

This graph illustrates the potential rise in CO2 emissions if

base-load electricity currently produced in the U.S. by nuclear power were replaced by coal or natural gas as current reactors go offline after their 60 year licenses expire. Note: graph assumes all 104 American nuclear power plants receive license extensions out to 60 years.

Economics The economics of new nuclear power plants is a

controversial subject, since there are diverging views on this topic, and multi-billion dollar investments ride on the choice of an energy source. Nuclear power plants typically have high capital costs for building the plant, but low fuel costs. Therefore, comparison with other power generation methods is strongly dependent on assumptions about construction timescales and capital financing for nuclear plants as well as the future costs of fossil fuels and renewables as well as for energy storage solutions for intermittent power sources. Cost estimates also need to take into account plant decommissioning and nuclear waste storage costs. On the other hand measures to mitigate global warming, such as a carbon tax or carbon emissions trading, may favor the economics of nuclear power.

In recent years there has been a slowdown of electricity demand growth and financing has become more difficult, which has an impact on large projects such as nuclear reactors, with very large upfront costs and long project cycles which carry a large variety of risks. In Eastern Europe, a number of long-established projects are struggling to find finance, notably Belene in Bulgaria and the additional reactors at Cernavoda in Romania, and some potential backers have pulled out. Where cheap gas is available and its future supply relatively secure, this also poses a major problem for nuclear projects.

Analysis of the economics of nuclear power must take into account who bears the risks of future uncertainties. To date all operating nuclear power plants were developed by state-owned or regulated utility monopolies where many of the risks associated with construction costs, operating performance, fuel price, accident liability and other factors were borne by consumers rather than suppliers. In addition, because the potential liability from a nuclear accident is so great, the full cost of liability insurance is generally limited/capped by the government, which the U.S. Nuclear Regulatory Commission concluded constituted a significant subsidy. Many countries have now liberalized the electricity market where these risks, and the risk of cheaper competitors emerging before capital costs are recovered, are borne by plant suppliers and operators rather than consumers, which leads to a significantly different evaluation of the economics of new nuclear power plants.

Following the 2011 Fukushima I nuclear accidents, costs are likely to go up for currently operating and new nuclear power plants, due to increased requirements for on-site spent fuel management and elevated design basis threats.

 Nuclear and radiation accidents Some serious nuclear and radiation accidents have

occurred. Nuclear power plant accidents include the Chernobyl disaster(1986), Fukushima Daiichi nuclear disaster (2011), and the Three Mile Island accident (1979). Nuclear-powered submarine mishaps include the K-19 reactor accident (1961), the K-27 reactor accident (1968) and the K-431 reactor accident (1985). International research is continuing into safety improvements such as passively safe plants,and the possible future use of nuclear fusion.

Nuclear power has caused far fewer accidental deaths per unit of energy generated than other major forms of power generation. Energy production from coal, natural gas, and hydropower have caused far more deaths due to accidents .However, nuclear power plant accidents rank first in terms of their economic cost, accounting for 41 percent of all property damage attributed to energy accidents.

Nuclear power organizations

Against Friends of the Earth

International, a network of environmental organizations in 77 countries.

Greenpeace Internatioal, a non-governmental environmental  organization  with offices in 41 countries.

Nuclear Information and Resource Service (International)

Sortir du nucléaire (Canada) Sortir du nucléaire (France) Pembina Institute (Canada) Institute for Energy and

Environmental Research (United States)

Supportive World Nuclear Association, a

confederation of companies connected with nuclear power production. (International)

International Atomic Energy Agency (IAEA)

Nuclear Energy Institute (United States)

American Nuclear Society (United States)

United Kingdom Atomic Energy Authority (United Kingdom)

EURATOM (Europe) Atomic Energy of Canada

Limited (Canada) Environmentalists for Nuclear

Energy (International)

Nuclear power plant in India

Nuclear power plant is the fourth largest source of electricity in India after thermal, hydroelectric and renewable sources of electricity. As of 2010, India has 20 nuclear reactors in operation in six nuclear power plants, generating 4,780 MW while seven other reactors are under construction and are expected to generate an additional 5,300  MW.

In October 2010, India drew up "an ambitious plan to reach a nuclear power capacity of 63,000 MW in 2032".  However, especially since the March 2011 Japanese Fukushima nuclear disaster, "populations around proposed Indian NPP sites have launched protests that are now finding resonance around the country, raising questions about atomic energy as a clean and safe alternative to fossil fuels".  Assurances by Prime Minister Manmohan Singh that all safety measures will be implemented, have not been heeded, and there have thus been mass protests against the French-backed 9900 MW Jaitapur Nuclear Power Project in Maharashtra and the 2000 MW Koodankulam Nuclear Power Plant in Tamil Nadu. The state government of West Bengal state has also refused permission to a proposed 6000 MW facility near the town of Haripur that intended to host six Russian reactors.

NUCLEAR POWER PLANTS IN INDIA

Power station Operator State Type UnitsTotal

capacity (MW)

Kaiga NPCIL Karnataka PHWR 220 x 4 880

Kakrapar NPCIL Gujarat PHWR 220 x 2 440

Kalpakkam NPCIL Tamil Nadu PHWR 220 x 2 440

Narora NPCIL Uttar Pradesh PHWR 220 x 2 440

Rawatbhata NPCIL Rajasthan PHWR100 x 1200 x 1220 x 4

1180

Tarapur NPCIL Maharashtra BWR (PHWR)160 x 2540 x 2

1400

Total 20 4780

Nuclear power plant accidents in India

Date Location DescriptionCost

(in millions2006 US$)

4 May 1987Kalpakkam, Tamil Nadu, India

Fast Breeder Test Reactor at Kalpakkam refueling accident that ruptures the reactor core, resulting in a two-year shutdown.

300

10 September 1989Tarapur, Maharashtra, India

Operators at the Tarapur Atomic Power Station find that the reactor had been leaking radioactive iodine at more than 700 times normal levels. Repairs to the reactor take more than a year.

78

13 May 1992Tarapur, Maharashtra, India

A malfunctioning tube causes the Tarapur Atomic Power Station to release 12 curies of radioactivity.

2

31 March 1993Bulandshahr, Uttar Pradesh, India

The Narora Atomic Power Station suffers a fire at two of its steam turbine blades, no damage to the reactor. All major cables burnt.

220

2 February 1995 Kota, Rajasthan, IndiaThe Rajasthan Atomic Power Station leaks radioactive helium and heavy water into the Rana Pratap Sagar dam, necessitating a two-year shutdown for repairs.

280

22 October 2002Kalpakkam, Tamil Nadu, India

Almost 100 kg radioactive sodium at a fast breeder reactor leaks into a purification cabin, ruining a number of valves and operating systems.

30

Accidents at nuclear power plants in India

India currently has twenty nuclear reactors in operation, and their safety record is far from clean.

Below is a list of leaks, fires and structural damages that have occurred in India’s civilian nuclear power sector.  Numerous other examples of oil leaks, hydrogen leaks, fires and high bearing vibrations have often shut plants, and sometimes not).

As the Department of Atomic Energy is not obliged to reveal details of ongoings at these plants to the public, there may be many other accidents that we do not know about. 

April 2011 Fire alarms blare in the control room of the Kaiga Generating Station in Karnataka.  Comments by officials alternately say there was no fire, that there was only smoke and no fire, and that the fire was not in a sensitive area (2).  Details from the AERB are awaited. 

November 2009 Fifty-five employees consume radioactive material after tritiated water finds its way into the drinking water cooler in Kaiga Generating Station. The NPCIL attributes the incident to “an insider’s mischief” (3).

April 2003 Six tonnes leak of heavy water at reactor II of the Narora Atomic  Power Station (NAPS) in Uttar Pradesh (4), indicating safety measures have not been improved from the leak at the same reactor three years previously.

January 2003 Failure of a valve in the Kalpakkam Atomic Reprocessing Plant in Tamil Nadu results in the release of high-level waste, exposing six workers to high doses of radiation (5). The leaking area of the plant had no radiation monitors or mechanisms to detect valve failure, which may have prevented the employees’ exposure. A safety committee had previously recommended that the plant be shut down.  The management blames the “over enthusiasm” of the workers (6).

May 2002 Tritiated water leaks from a downgraded heavy water storage tank at the tank farm of Rajasthan Atomic Power Station (RAPS) 1&2 into a common dyke area.  An estimated 22.2 Curies of radioactivity is released into the environment (7).

November 2001 A leak of 1.4 tonnes of heavy water at the NAPS I reactor, resulting in one worker receiving an internal radiation dose of 18.49 mSv (8).

April 2000 Leak of about seven tonnes of heavy water from the moderator system at NAPS Unit II. Various workers involved in the clean-up received ‘significant uptakes of tritium’, although only one had a radiation dose over the recommended annual limit (9). 

March 1999 Somewhere between four and fourteen tonnes (10) of heavy water leaks from the pipes at Madras Atomic Power Station (MAPS) at Kalpakkam, Tamil Nadu, during a test process. The pipes have a history of cracks and vibration problems (11) . Forty-two people are reportedly involved in mopping up the radioactive liquid (12).

May 1994 The inner surface of the containment dome of Unit I of Kaiga Generating Station collapses (delaminates) while the plant is under construction. Approximately 130 tonnes of concrete fall from a height of nearly thirty metres (13), injuring fourteen workers. The dome had already been completed (14), forming the part of the reactor designed to prevent escape of radioactive material into the environment in the case of an accident.  Fortunately, the core had not then been loaded.

February 1994 Helium gas and heavy water leak in Unit 1 of RAPS.  The plant is shut down until March 1997 (15). March 1993 Two blades of the turbine in NAPS Unit I break off, slicing through other blades and indirectly causing a raging fire,

which catches onto leaked oil and spreads through the turbine building.  The smoke sensors fail to detect the fire, which is only noticed once workers see the flames.  It causes a blackout in the plant, including the shutdown of the secondary cooling systems, and power is not restored for seventeen hours.  In the meantime, operators have to manually activate the primary shutdown system.  They also climb onto the roof to open valves to slow the reactions in the core by hand (16).  The incident was rated as a Level 3 on the International Nuclear Event Scale, INES.

May 1992 Tube leak causes a radioactive release of 12 Curies of radioactivity from Tarapur Atomic Power Station (17).

January 1992 Four tons of heavy water spilt at RAPS (17). December 1991 A leak from pipelines in the vicinity of CIRUS and Dhruva research reactors at the Bhabha Atomic Research

Centre (BARC) in Trombay, Maharashtra, results in severe Cs-137 soil contamination of thousands of times the acceptable limit. Local vegetation was also found to be contaminated, though contract workers digging to the leaking pipeline were reportedly not tested for radiation exposure, despite the evidence of their high dose (18).

July 1991 A contracted labourer mistakenly paints the walls of RAPS with heavy water before applying a coat of whitewash. He also washed his paintbrush, face and hands in the deuterated and tritiated water, and has not been traced since (19).

Anti-nuclear protests Following the Fukushima disaster, many are questioning the mass

roll-out of new plants in India, including the World Bank, the former Indian Environment Minister, Jairam Ramesh, and the former head of the country's nuclear regulatory body, A. Gopalakrishnan. The massive Jaitapur Nuclear Power Project is the focus of concern — "931 hectares of farmland will be needed to build the reactors, land that is now home to 10,000 people, their mango orchards, cashew trees and rice fields" — and it has attracted many protests. Fishermen in the region say their livelihoods will be wiped out.

Environmentalists, local farmers and fishermen have been protesting for months over the planned six-reactor nuclear power complex on the plains of Jaitapur , 420 km south of Mumbai. If built, it would be one of the world's largest nuclear power complexes. Protests have escalated in the wake of Japan's Fukushima I nuclear accidents. During two days of violent rallies in April 2011, a local man was killed and dozens were injured.

As of October 2011, thousands of protesters and villagers living around the Russian-built Koodankulam nuclear plant in the southern Tamil Nadu province, are blocking highways and staging hunger strikes, preventing further construction work, and demanding its closure as they distrust federal government assurances regarding safety. They fear there will be a nuclear accident similar to the radiation leak in March at Japan's Fukushima nuclear disaster.

The Fukushima Daiichi nuclear disaster The Fukushima Daiichi nuclear disaster is a series of

equipment failures, nuclear meltdowns, and releases of radioactive materials at the Fukushima I Nuclear Power Plant, following the Tōhok earthquake and tsunami on 11 March 2011.It is the largest nuclear disaster since the Chernobyl disaster of 1986.

The plant comprises six separate boiling water reactors originally designed by General Electric (GE), and maintained by the Tokyo Electric Power Company (TEPCO). At the time of the quake, Reactor 4 had been de-fuelled while 5 and 6 were in cold shutdown for planned maintenance.The remaining reactors shut down automatically after the earthquake, and emergency generators came online to control electronics and coolant systems. The tsunami broke the reactors' connection to the power grid, leading the reactors to begin to overheat. The flooding and earthquake damage hindered external assistance.

In the hours and days that followed, reactors 1, 2 and 3 experienced full meltdown. As workers struggled to cool and shut down the reactors, several hydrogen explosions occurred. The government ordered that seawater be used to attempt to cool the reactors—this had the effect of ruining the reactors entirely. As the water levels in the fuel rods pools dropped, they began to overheat. Fears of radioactivity releases led to a 20 km (12 mi)-radius evacuation around the plant, while workers suffered radiation exposure and were temporarily evacuated at various times. Electrical power was slowly restored for some of the reactors, allowing for automated cooling.

The Japanese government estimates the total amount of radioactivity released into the atmosphere was approximately one-tenth as much as was released during the Chernobyl disaster. Significant amounts of radioactive material have also been released into ground and ocean waters. Measurements taken by the Japanese government 30–50 km from the plant showed radioactive caesium levels high enough to cause concern, leading the government to ban the sale of food grown in the area. Tokyo officials temporarily recommended that tap water should not be used to prepare food for infants.

A few of the plant's workers were severely injured or killed by the disaster conditions resulting from the earthquake. There were no immediate deaths due to direct radiation exposures, but at least six workers have exceeded lifetime legal limits for radiation and more than 300 have received significant radiation doses. Future cancer deaths due to accumulated radiation exposures in the population living near Fukushima have been estimated to be between 100 and 1,000.Fear of ionizing radiation could have long-term psychological effects on a large portion of the population in the contaminated areas. On 16 December 2011 Japanese authorities declared the plant to be stable, although it would take decades to decontaminate the surrounding areas and to decommission the plant altogether.

The Fukushima Daiichi nuclear disaster

ISSUES STILL GOES ON …

In conclusionThe issue of using nuclear power to produce

electricity involves its high cost, its waste, and the public's concern of its safe usage. Nuclear power is very expensive and complicated, but provides reliable, efficient power. The radioactive waste produced by a nuclear plant, however, is very dangerous and difficult to store safely. Many people do not feel safe having nuclear plants near their homes. They fear that a nuclear accident could destroy their happy lives. As long as the world needs electricity, however, there will be nuclear power. People will continue to discuss the issue of nuclear power for a long time to come.