Nuclear Power Issue

Nuclear power debate

The nuclear power debate is about the controversy which has surrounded the deployment and use of nuclear fission reactors to generate electricityfrom nuclear fuel for civilian purposes. The debate about nuclear power peaked during the 1970s and 1980s, when it "reached an intensity unprecedented in the history of technology controversies", in some countries.

Proponents of nuclear energy argue that nuclear power is a sustainable energy source which reduces carbon emissions and can increase energy security if its use supplants a dependence on imported fuels.Proponents advance the notion that nuclear power produces virtually no air pollution, in contrast to the chief viable alternative of fossil fuel. Proponents also believe that nuclear power is the only viable course to achieve energy independence for most Western countries. They emphasize that the risks of storing waste are small and can be further reduced by using the latest technology in newer reactors, and the operational safety record in the Western world is excellent when compared to the other major kinds of power plants.

Opponents say that nuclear power poses many threats to people and the environment. These threats include health risks and environmental damage fromuranium mining, processing and transport, the risk of nuclear weapons proliferation or sabotage, and the unsolved problem of radioactive nuclear waste.They also contend that reactors themselves are enormously complex machines where many things can and do go wrong, and there have been many serious nuclear accidents.Critics do not believe that these risks can be reduced through new technology.They argue that when all the energy-intensive stages of the nuclear fuel chain are considered, from uranium mining to nuclear decommissioning, nuclear power is not a low-carbon electricity source.

Issues

Seven reasons why people should say "yes" to nuclear power:

• Because nuclear fuel is virtually unlimited and packs a huge energy punch
• Because new technology solves the "nuclear waste" problem
• Because nuclear power is the safest energy option
• Because advanced nuclear power will strengthen global security
• Because nuclear power's true costs are lower than either fossil fuels or renewables
• Because nuclear power can lead the "clean energy" revolution

there are seven reasons why people should say "no" to nuclear power:

• Because it is not a fast enough response to climate change
• Because it is too expensive
• Because the need for baseload electricity is exaggerated
• Because the problem of waste remains unresolved
• Because it will increase the risk of nuclear war
• Because there are safety concerns
• Because there are better alternatives

Energy supplied

Many studies have documented how nuclear power plants generate 16% of global electricity, but provide only 6.3% of energy production and 2.6% of final energy consumption. This mismatch stems mainly from the poor consumption efficiency of electricity compared to other energy carriers, and the transmission losses associated with nuclear plants which are usually situated far away from sources of demand.

Energy security

For some countries, nuclear power affords energy independence. Nuclear power has been relatively unaffected by embargoes, and uranium is mined in countries willing to export, including Australia and Canada.However, countries now responsible for more than 30% of the world’s uranium production: Kazakhstan, Namibia, Niger, and Uzbekistan, are politically unstable.

Reserves from existing uranium mines are being rapidly depleted, and one assessment from the IAEA showed that enough high-grade ore exists to supply the needs of the current reactor fleet for only 40-50 years.Expected shortfalls in available fuel threaten future plants and contribute to volatility of uranium prices at existing plants. Uranium fuel costs have escalated in recent years, which negatively impacts on the viability of nuclear projects.

According to a Stanford study, fast breeder reactors have the potential to provide power for humans on earth for billions of years, making this source sustainable.But "because of the link between plutonium and nuclear weapons, the potential application of fast breeders has led to concerns that nuclear power expansion would bring in an era of uncontrolled weapons proliferation".

Reliability

In 2005, out of all nuclear power plants in the world, the average capacity factor was 86.8%, the number of SCRAMs per 7,000 hours critical was 0.6, and the unplanned capacity loss factor was 1.6%.Capacity factor is the net power produced divided by the maximum amount possible running at 100% all the time, thus this includes all scheduled maintenance/refueling outages as well as unplanned losses. The 7,000 hours is roughly representative of how long any given reactor will remain critical in a year, meaning that the scram rates translates into a sudden and unplanned shutdown about 0.6 times per year for any given reactor in the world. The unplanned capacity loss factor represents amount of power not produced due to unplanned scrams and postponed restarts.

The World Nuclear Association argues that: "Obviously sun, wind, tides and waves cannot be controlled to provide directly either continuous base-load power, or peak-load power when it is needed,..." "In practical terms non-hydro renewables are therefore able to supply up to some 15–20% of the capacity of an electricity grid, though they cannot directly be applied as economic substitutes for most coal or nuclear power, however significant they become in particular areas with favourable conditions." "If the fundamental opportunity of these renewables is their abundance and relatively widespread occurrence, the fundamental challenge, especially for electricity supply, is applying them to meet demand given their variable and diffuse nature. This means either that there must be reliable duplicate sources of electricity beyond the normal system reserve, or some means of electricity storage." "Relatively few places have scope for pumped storage dams close to where the power is needed, and overall efficiency is less than 80%. Means of storing large amounts of electricity as such in giant batteries or by other means have not been developed."

According to a 2011 projection by the International Energy Agency, solar power generators may produce most of the world’s electricity within 50 years, with wind power, hydroelectricity and biomass plants supplying much of the remaining generation. "Photovoltaic and concentrated solar power together can become the major source of electricity".Renewable technologies can enhance energy security inelectricity generation, heat supply, and transportation.

Since nuclear power plants are fundamentally heat engines, waste heat disposal becomes an issue at high ambient temperature. Droughts and extended periods of high temperature can “cripple nuclear power generation, and it is often during these times when electricity demand is highest because of air-conditioning and refrigeration loads and diminished hydroelectric capacity”. In such very hot weather a power reactor may have to operate at a reduced power level or even shut down.In the 2006 European heat wave, a number of nuclear plants had to secure exemptions from regulations in order to discharge overheated water into the environment; several European nations were forced to reduce operations at some plants and take others offline and France, normally an electricity exporter, had to buy electricity on European spot market to meet demand.In 2009 in Germany, eight nuclear reactors had to be shut down simultaneously on hot summer days for reasons relating to the overheating of equipment or of rivers.Overheated discharge water has resulted in significant fish kills in the past, impacting livelihood and raising public concern.

Economics

New nuclear plants

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 direct fuel costs (with much of the costs of fuel extraction, processing, use and long term storage externalized). Therefore, comparison with other power generation methods is strongly dependent on assumptions about construction timescales and capital financing for nuclear plants. 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, and other factors were borne by consumers rather than suppliers. 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 Daiichi nuclear disaster, 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.

Subsidies

Critics of nuclear power claim that it is the beneficiary of inappropriately large economic subsidies — mainly taking the forms of research and development, and financing support for new build — and that these subsidies are often overlooked when comparing the economics of nuclear against other forms of power generation.

Nuclear industry proponents argue that competing energy sources also receive subsidies. Fossil fuels receive large direct and indirect subsidies, such as tax benefits and not having to pay for thegreenhouse gases they emit. Renewables receive proportionately large direct production subsidies and tax breaks in many nations, although in absolute terms they are often less than subsidies received by other sources.

Energy research and development (R&D) for nuclear power continues to receive large state subsidies. In the United States, nuclear receives more Federal R&D support than the renewables industry[citation needed], however the impact of favorable tax incentives drives the total Federal support of the renewables industry to a level almost four times as high as that of the nuclear industry, despite all renewables (excluding hydroelectric, which receives no R&D funding) producing only 1/8 as much power as nuclear.In Europe, the FP7 research program has more subsidies for nuclear than for renewable and energy efficiency together, although over 70% of this is directed at the ITER fusion project.In the US, public research money for nuclear fission declined from 2,179 to 35 million dollars between 1980 and 2000.

A May 12, 2008 editorial in the Wall St. Journal stated, "For electricity generation, the EIA concludes that solar energy is subsidized to the tune of $24.34 per megawatt hour, wind $23.37 and 'clean coal' $29.81. By contrast, normal coal receives 44 cents, natural gas a mere quarter, hydroelectric about 67 cents and nuclear power $1.59."The impacts of prior subsidies, some of which may no longer be in effect, are not measured in the previous analysis. However, the Renewable Energy Policy Project stated that from 1947 to 1999, nuclear power was subsidized $145.4 billion, wind power $1.2 billion and solar $4.4 billion.From a megawatt hour basis, this translates into $12.45 per MWh produced for nuclear power, $36.47 for wind power and $511.63 for solar (1999 dollars).

Environmental effects

The primary environmental impacts of nuclear power come from uranium mining, radioactive effluent emissions, and waste heat, as under normal generating conditions nuclear power does not producegreenhouse gas emissions [CO2, NO2] directly (although the nuclear fuel cycle produces them indirectly, though at much smaller rates than fossil fuels).Nuclear generation does not directly produce sulfur dioxide, nitrogen oxides, mercury or other pollutants associated with the combustion of fossil fuels. In 2008, The Economist stated that "nuclear reactors are the one proven way to make carbon-dioxide-free electricity in large and reliable quantities that does not depend (as hydroelectric and geothermal energy do) on the luck of the geographical draw."Many experts, some of whom consider themselves environmentalists, now believe that expanded nuclear generation is the only way to reduce green house gas emissions while providing for current and future electricity needs.[citation needed]However, this is disputed in the literature because of the basic thermodynamic limits to nuclear energy deployment.

While nuclear power does not directly emit greenhouse gasses, over a facility's life cycle, emissions occur through plant construction, operation, uranium mining and milling, and plant decommissioning. Ameta analysis of 103 life cycle studies by Benjamin K. Sovacool, found that nuclear power plants produce electricity with about 66 g equivalent lifecycle carbon dioxide emissions per kWh, while renewable power generators produce electricity with only 9.5-38 g carbon dioxide per kWh.This work on carbon emissions from nuclear power stations has been reviewed in Nature. A study done at the University of Wisconsin showed all non-fossil sources are roughly equal in reducing greenhouse-gas emissions.

Nuclear plants require more, but not significantly more, cooling water than fossil-fuel power plants due to their slightly lower generation efficiencies. Uranium mining can use large amounts of water — for example, the Roxby Downs mine in South Australia uses 35 million litres of water each day and plans to increase this to 150 million litres per day.

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.

Disposal of nuclear waste is often said to be the Achilles' heel of the nuclear industry.Presently, waste is mainly stored at individual reactor sites and there are over 430 locations around the world where radioactive material continues to accumulate. Experts agree that centralized underground repositories which are well-managed, guarded, and monitored, would be a vast improvement.There is an international consensus on the advisability of storing nuclear waste in deep underground repositories,but no country in the world has yet opened such a site.

Safety and accidents

The abandoned city of Prypiat, Ukraine, following the Chernobyl disaster. The Chernobyl nuclear power plant is in the background.

The nuclear power industry has improved the safety and performance of reactors, and has proposed new safer (but generally untested) reactor designs but there is no guarantee that the reactors will be designed, built and operated correctly.Mistakes do occur and the designers of reactors at Fukushima in Japan did not anticipate that a tsunami generated by an earthquake would disable the backup systems that were supposed to stabilize the reactor after the earthquake.According to UBS AG, the Fukushima I nuclear accidents have cast doubt on whether even an advanced economy like Japan can master nuclear safety.Catastrophic scenarios involving terrorist attacks are also conceivable.An interdisciplinary team from MIT have estimated that given a three-fold increase in nuclear power from 2005 to 2055, and an unchanged accident frequency, four core damage accidents would be expected in that period.

The impact of nuclear accidents has been a topic of debate practically since the first nuclear reactors were constructed. It has also been a key factor in public concern about nuclear facilities.Some technical measures to reduce the risk of accidents or to minimize the amount of radioactivity released to the environment have been adopted. Despite the use of such measures, "there have been many accidents with varying impacts as well near misses and incidents".

Health effects on population near nuclear power plants and workers

Fishermen near the now-dismantled Trojan Nuclear Power Plant in Oregon. The reactor dome is visible on the left, and the cooling tower on the right.

A major concern in the nuclear debate is what the long-term effects of living near or working in a nuclear power station are. These concerns typically center around the potential for increased risks of cancer. However, studies conducted by non-profit, neutral agencies have found no compelling evidence of correlation between nuclear power and risk of cancer.

There has been considerable research done on the effect of low-level radiation on humans. Debate on the applicability of Linear no-threshold model versus Radiation hormesis and other competing models continues, however, the predicted low rate of cancer with low dose means that large sample sizes are required in order to make meaningful conclusions. A study conducted by the National Academy of Science found that carcinogenic effects of radiation does increase with dose.The largest study on nuclear industry workers in history involved nearly a half-million individuals and concluded that a 1–2% of cancer deaths were likely due to occupational dose. This was on the high range of what theory predicted by LNT, but was "statistically compatible".

Scientists learned about exposure to high level radiation from studies of the effects of bombing populations at Hiroshima and Nagasaki. However, it is difficult to trace the relationship of low level radiation exposure to resulting cancers and mutations. This is because the latency period between exposure and effect can be 25 years or more for cancer and a generation or more for genetic damage. Since nuclear generating plants have a brief history, it is early to judge the effects.

Public opinion

A poll in the European Union for Feb-Mar 2005 showed 37% in favour of nuclear energy and 55% opposed, leaving 8% undecided.The same agency ran another poll in Oct-Nov 2006 that showed 14% favoured building new nuclear plants, 34% favoured maintaining the same number, and 39% favoured reducing the number of operating plants, leaving 13% undecided. This poll showed that the approval of nuclear power rose with the education level of respondents.

The two fuel sources that attracted the highest levels of support in the 2007 MIT Energy Survey are solar power and wind power. Outright majorities would choose to “increase a lot” use of these two fuels, and better than three out of four Americans would like to increase these fuels in the U. S. energy portfolio. Fourteen per cent of respondents would like to see nuclear power "increase a lot".

What had been growing acceptance of nuclear power in the United States was eroded sharply following the 2011 Japanese nuclear accidents, with support for building nuclear power plants in the U.S. dropping slightly lower than it was immediately after the Three Mile Island accident in 1979, according to a CBS News poll. Only 43 percent of those polled after the Fukushima nuclear emergency said they would approve building new power plants in the United States.

A 2011 poll suggests that skepticism over nuclear power is growing in Sweden following Japan's nuclear crisis. 36 percent of respondents want to phase-out nuclear power, up from 15 percent in a similar survey two years ago.

In 2011, London-based bank HSBC said: "With Three Mile Island and Fukushima as a backdrop, the US public may find it difficult to support major nuclear new build and we expect that no new plant extensions will be granted either. Thus we expect the clean energy standard under discussion in US legislative chambers will see a far greater emphasis on gas and renewables plus efficiency".

In 2011, Deutsche Bank analysts concluded that "the global impact of the Fukushima accident is a fundamental shift in public perception with regard to how a nation prioritizes and values its populations health, safety, security, and natural environment when determining its current and future energy pathways". As a consequence, "renewable energy will be a clear long-term winner in most energy systems, a conclusion supported by many voter surveys conducted over the past few weeks. At the same time, we consider natural gas to be, at the very least, an important transition fuel, especially in those regions where it is considered secure".

Future of the nuclear industry

As of May 15, 2011, a total of 438 nuclear reactors were operating in 30 countries, six fewer than the historical maximum of 444 in 2002. Since 2002, utilities have started up 26 units and disconnected 32 including six units at the Fukushima Daiichi nuclear power plant in Japan. The current world reactor fleet has a total nominal capacity of about 372 gigawatts (or thousand megawatts). Despite six fewer units operating in 2011 than in 2002, the capacity is still about 9 gigawatts higher. The numbers of new operative reactors, final shutdowns and new initiated constructions according to International Atomic Energy Agency (IAEA) in recent years are as follows:

Following the Fukushima Daiichi nuclear disaster, the International Energy Agency halved its estimate of additional nuclear generating capacity to be built by 2035.Platts has reported that "the crisis at Japan's Fukushima nuclear plants has prompted leading energy-consuming countries to review the safety of their existing reactors and cast doubt on the speed and scale of planned expansions around the world". In 2011, The Economist reported that nuclear power "looks dangerous, unpopular, expensive and risky", and that "it is replaceable with relative ease and could be forgone with no huge structural shifts in the way the world works".

In September 2011, German engineering giant Siemens announced it will withdraw entirely from the nuclear industry, as a response to the Fukushima nuclear disaster in Japan.The company is to boost its work in the renewable energy sector.

As Time magazine rightly stated in March, "Nuclear power is expanding only in places where taxpayers and ratepayers can be compelled to foot the bill." China is building 27 -- or more than 40 percent -- of the 65 units officially under construction around the world. Even there, though, nuclear is fading as an energy option. While China has invested the equivalent of about $10 billion per year into nuclear power in recent years, in 2010 it spent twice as much on wind energy alone and some $54.5 billion on all renewables combined.

                                                                                                     -by Anirudha Sant(Last Minute Group)