Dr.DEBESH BHOWMIK

Dr.DEBESH BHOWMIK

Tuesday 3 September 2013

CLIMATE CHANGE AND NUCLEAR POWER



Climate Change and Nuclear Energy

---Dr.Debesh Bhowmik

The World Energy Outlook estimates that global energy use will have increased by 67% in 2030 compared to levels in 2000 (IEA, 2002), and it is generally accepted that world energy demand will double by 2050 (WNA, 2004a). How to satisfy these energy demands while simultaneously reducing greenhouse gas emissions is one of the most pressing questions of our time.
Their arguments are summed up in the following statement by the World Energy Council (WEC): "Nuclear power is of fundamental importance for most WEC members because it is the only energy supply which already has a very large and well diversified resource (and potentially
unlimited resource if breeders are used), is quasi-indigenous, does not emit greenhouse gases,
and has either favourable or at most slightly unfavourable economics. In fact should the climate
change threat become a reality, nuclear is the only existing power technology which could
replace coal in base load."
However, their argumentsare based on a number of myths, namely that:
[i] Nuclear power does not emit greenhouse gases;
[ii] There is a plentiful supply of fuel for the nuclear fission process;
[iii] Nuclear power is economically viable;
[iv] There are no viable alternative solutions;
[v] There are no other major problems associated with nuclear power;
[vi] The fast breeder technology will eventually mature and provide unlimited resources.
The arguments for nuclear power as a potential mitigator of GHG emissions have not gone away; nor has the need for such mitigators. The countries attending the 2011 G8 Summit in Deauville, France, confirmed their commitment to long term efforts to limit “the increase in global temperatures [to] below 2°C above pre-industrial levels, consistent with science” and their support for “reducing emissions of greenhouse gases in aggregate by 80% or more by 2050, compared to 1990” in developed countries .
Nuclear power has the potential to continue to play a significant role in the effort to limit future GHG emissions while meeting global energy needs. Nuclear power plants produce virtually no GHG emissions during their operation and only very small amounts on a life cycle basis. Yet the scientific consensus is that GHG emissions will need to peak within the next decade or so and then decline by 50%– 85% from today’s levels by 2050 in order to avoid adverse climate change impacts in ecological and socioeconomic systems. The twin challenges over the next 10–20 years will be to keep promoting economic development by providing reliable, safe and affordable energy services while significantly reducing GHG emissions.
Nuclear power is among the energy sources and technologies available today that could help meet the climate– energy challenge. In the electricity sector, nuclear power has been assessed as having the greatest potential (1.88 Gt CO2-equivalent (CO2-eq.)) to mitigate GHG emissions at the lowest cost: 50% of the potential at negative costs due to co-benefits from reduced air pollution, the other 50% at less than $20/t CO2-eq. Nuclear energy could account for about 15% of the total GHG reduction in electricity generation by 2050. Nuclear energy can contribute to resolving other energy supply concerns and has non-climatic environmental benefits. The economics of nuclear power are competitive and will be further enhanced by the increasing CO2 costs of fossil based electricity generation.
The estimated ranges of levelized electricity costs from natural gas, coal and nuclear sources largely overlap between 5 and 10 US cents/kW•h. Including the costs of CO2 capture and geological disposal and increasing charges for CO2 emissions would further improve the competitiveness of nuclear power.

The above arguments can be challenged in the following manners.
Nuclear power could at best make only a negligible contribution to CO2 reduction; even then many years after massive cuts are needed and only by depriving real climate solutions of funding. Currently 439 commercial nuclear reactors3 supply around 15 percent of global electricity, providing only 6.5 per cent of overall energy consumption.4 Even if today’s current installed nuclear capacity was doubled it would lead to reductions in global greenhouse gas emissions of less than five percent and would require one new large reactor to come online every two weeks until 2030. An impossible task: even in countries with established nuclear programmes, planning, licensing and connecting a new reactor to the grid typically takes more than a decade. Worldwide, plans for more than 200 new reactors have been announced; even under the most optimistic conditions, only a small fraction of these would be able to generate electricity before 2020.
As of 2008, thirty-one countries 4 operated 441 nuclear power plants 5 representing about 372 gigawatts ("GW") of total installed capacity.  Together, the world's fleet of nuclear power plants represents roughly 12,600 reactor years of experience. Moreover, "[fifty-six ] countries operate... 284 research reactors and a further 220 reactors are used to power ships and submarines," bringing the world total to 943 nuclear reactors.' In 2005, nuclear plants supplied 15 percent of the world's power, generating a total of 2768 terawatt-hours ("TWh") of electricity.19 In the U.S. alone, which has 29.2 percent of the world's reactors, nuclear facilities accounted for just 19 percent of the national electricity generation." In France, however, 79 percent of electricity comes from nuclear sources, and nuclear energy contributes to more than 20 percent of national power production in Germany, Japan, South Korea, Sweden, Ukraine, and the United Kingdom.
It is true that the actual fission process whereby electricity is generated does not release
greenhouse gases. However, in various stages of the nuclear process (e.g. mining, uranium
enrichment, building and decommissioning of power plants, processing and storing radioactive
waste) huge amounts of energy are needed, much more than for less complex forms of electricity
production. Most of this energy comes in the form of fossil fuels, and therefore nuclear
power indirectly generates a relatively high amount of greenhouse gas emissions.
Table-1:GHG Emission from different sources
Generation Method /Greenhouse Gas Emissions (CO2-eq. /kWh)
[a]W ind /20
[b]Hydroelectric /33
[c]Nuclear /35
[d]Gas Combined Cycle /Ca. 400
[e] Coal /Ca. 1000
From the data above it can be concluded that nuclear power emits about the same quantity of
greenhouse gases as electricity produced from a number of renewable sources, but much
less than fossil fuel sources: 12 times less than gas power stations and almost 30 times less
than coal power stations. Much of these emissions occur when energy is used for the mining
of uranium, during transports and in the enrichment process that makes uranium usable as
reactor fuel. The emissions during decommissioning of a nuclear reactor are probably underestimated in these analyses, because in practice these emissions turn out to be much higher
than was assumed theoretically.
In a number of other studies similar emissions data are reported, where nuclear power emissions
are calculated in the range of 30-60 g CO2-eq. /kWh .
According to their data, nuclear power production causes the emission of just 3 times
fewer greenhouse gases than modern natural gas power stations. This figure is based on rich
ores with over 0.1% uranium content. Moreover they expect a dramatic decrease of the percentage of uranium content in ores, which will make the extraction of the uranium much more
energy consuming. The emissions from the nuclear industry are strongly dependent on the
percentage of uranium in the ores used to fuel the nuclear process. The global average uranium
content in ores is currently about 0.15% .
We have calculated the number of new nuclear power stations that would be needed to reduce the emissions of the public energy sector by 2012 according to the targets of the Kyoto Protocol in the EU-15 (EU prior to the expansion). Although the Protocol does not actually stipulate the sectors in which emissions reductions are to be made, we have made the calculations assuming that each sector contributes according to the levels of its current contribution to total emissions. This means that while this sector accounts for 39% of emissions it should be responsible for 39% of emissions reductions .
Assuming that electricity generation from nuclear power plants does indeed cause the indirect
emission of 35g CO2-eq./kWh (Öko, 1997), 72 new medium sized plants of 500MW each
would be required in the EU-15. (For an explanation of the calculations and assumptions
please refer to appendix 1). These would have to be built before the end of the first commitment
period 2008-2012. Leaving aside the huge costs this would involve, it is unlikely that it is
technically feasible to build so many new plants in such a short time, given that only 15 new
reactors have been built in the last 20 years (WISE, 2003). Furthermore, with so many new
reactors, the world supply of uranium would be exhausted very quickly.
Note that that [i]Electricity is only a small part of the climate problem.[ii]Nuclear energy is neither sustainable nor infinite. [iii]Nuclear power expansion increases the risk of an accident
[iv]Nuclear power expansion would increase the volume and unresolved risks of spent nuclear fuel and radioactive waste far into the distant future.[v] Nuclear power expansion would seriously undermine global security by significantly increasing opportunities for nuclear proliferation and terrorism.[vi] To propose nuclear expansion in the name of climate change is effectively adding one uncertain, potentially catastrophic health,environmental and security threat to another. Nuclear power poses an unacceptable health, safety and security risk. In fact, as climate change impacts increase, so too do the safety risks associated with nuclear power.
[vii]In addition to the routine discharges from nuclear operation radiation exposure is caused by mining the uranium used to make the fuel for the nuclear reactors. Uranium miners - such as those in Canada, the USA, Namibia and Sweden - breathe radon which is derived from uranium. This gets into their lungs where it emits so-called ‘alpha particles’ which can cause lung cancer. One risk assessment indicates that each year 44 uranium miners receive fatal doses of radiation.
[viii]The RoyalCommission on Environmental Pollution stated; ”We must assume that these wastes will remain dangerous and will need to be isolated from the biosphere for hundreds of thousands of years. In considering arrangements for dealing safely with such wastes man is faced with timescales that transcend his experience.
In 1976 the Royal Commission on Environmental Pollution concluded:“it is entirely credible that plutonium in the requisite amounts could be made into a crude but very effective weapon that would be transportable in a small vehicle. The threat to explode such a weapon unless certain conditions were met would constitute nuclear blackmail and would present any government with an appalling dilemma. ...We should not rely for energy supply on a process that produces such a hazardous substance as plutonium unless there is no reasonable alternative.
[ix] The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) periodically carries out assessments of exposures of the public and workers to various sources of radiation, including natural sources, enhanced sources of naturally occurring radioactive material, manufactured sources for peaceful purposes such as nuclear power production and medical use of radiation, and manufactured sources for military purposes including nuclear testing. According to UNSCEAR’s latest report , the average worldwide public exposure from globally dispersed radio nuclides from nuclear fuel cycle installations is estimated to be 0.18 μSv per person per year of operation. Average annual exposure to local populations is 25 μSv for mining and milling (within 100 km of the site), 0.2 μSv for uranium enrichment and fuel fabrication, 0.1 μSv for nuclear power reactors and 2 μSv for fuel reprocessing (within 50 km of the site). The World Health Organization released a report on 23 May 2012 assessing radiation exposure for the first year following the Fukushima–Daiichi accident. In the two areas with the highest impact within Fukushima prefecture, the dose is between 10 and 50 μSv. Outside of these two areas, but within Fukushima prefecture, the dose is estimated to be between 1 and 10 μSv. Estimates for exposure in the rest of Japan are between 0.1 and 1 μSv and for the rest of the world are below 0.01 μSv .
 Radiation exposure levels stemming from uranium mining, refining and nuclear power generation facilities are significantly lower than naturally occurring radiation exposure levels. In the case of a major nuclear accident, radioactive contamination of the environment close to the site can be severe, but exposure levels within areas nearest Fukushima–Daiichi are significantly below natural background radiation levels. The global averages are shown in the coloured bars, and regional variations are indicated with error bars. Major sources of external exposure are cosmic rays from outer space and natural terrestrial radionuclides existing in the Earth’s soil and in building materials such as granite and marble. The level of exposure to cosmic rays depends primarily on latitude and altitude. Exposure also arises from the intake of radionuclides in the Earth’s soil by inhalation (mainly radon) and ingestion (in the form of food and drinking water). Altogether, worldwide exposure to natural radiation sources for an average individual is 2420 μSv per year, with a typical range of between 1000 and 13 000 μSv per year . 
 
Lastly, Nuclear smuggling – much of it from civil nuclear programs – presents a significant challenge. The IAEA’s Illicit Trafficking Database records over 650 confirmed incidents of trafficking in nuclear or other radioactive materials since 1993. In 2004 alone, almost 100 such incidents occurred. Smuggling can potentially provide fissile material for nuclear weapons and a wider range of radioactive materials for use in ‘dirty bombs’. Civil nuclear plants are potentially “attractive” targets for terrorist attacks because of the importance of the electricity supply system in many societies, because of the large radioactive inventories in many facilities, and because of the potential or actual use of ‘civil’ nuclear facilities for weapons research or production.A 2004 study by the Union of Concerned Scientists concluded that a major terrorist attack on the Indian Point reactor in the US could result in as many as 44,000 near-term deaths from acute radiation syndrome and as many as 518,000 long-term deaths from cancer among individuals within fifty miles of the plant. The attack would pose a severe threat to the entire New York metropolitan area. Economic damages could be as great as US$2.1 trillion.

The IAEA Director-General Mohamed El Baradei in 2005 addressed a range of serious nuclear security problems in his address to the 2005 Non-Proliferation Treaty Review Conference: “In five years, the world has changed. Our fears of a deadly nuclear detonation – whatever the cause – have been reawakened. In part, these fears are driven by new realities. The rise in terrorism, the discovery of clandestine nuclear programmes, the emergence of a nuclear black market etc. But these realities have also heightened our awareness of vulnerabilities in the NPT regime. The acquisition by more and more countries are sensitive nuclear know-how and capabilities. There is  uneven degree of physical protection of nuclear materials from country to country. The limitations in the IAEA’s verification authority – particularly in countries without additional protocols are in force. The continuing reliance is on nuclear deterrence. The ongoing perception of imbalance between the nuclear haves and have-nots prevail. And the sense of insecurity persists, unaddressed, in a number of regions, most worryingly in the Middle East and the Korean Peninsula.”
The Economic reasons why nuclear power will not be favoured against renewables and energy efficiency, unless it receives a subsidy, are that it is far too expensive to consider realistically. In February 2000 the Nuclear Energy Agency of the OECD published a report on ‘Reduction of Capital Costs of Nuclear Power Plants’.It was reported that there had been very few orders for nuclear power since the early 1990s and that energy liberalisation would place nuclear economics under increased scrutiny. It was noted that although attempts have been made to cut capital costs of nuclear - which account for some 60% of generation costs – through development of new reactor designs “[t]o date it is not clear to what extent this had been achieved.” However, it was noted that in the future significant technical progress is needed to reduce capital costs and increase efficiency. The report concluded: “In order for nuclear power to remain a viable option for the next millennium, the cost of electricity from nuclear power plant must be greatly reduced to be competitive with alternative sources.Research financed by the British Nuclear Industry Forum concluded that nuclear power required a subsidy of the order of £232 per year per kW of installed capacity. It was noted above that some renewable are cheaper than coal and nuclear and therefore require no subsidy. Gordon MacKerron, senior fellow in science and technology policy research at the University of Sussex has stated: “it will still be the case for most of the countries most of the time that nuclear power will not be the best way of reducing carbon emissions.Although at present the future is bleak for nuclear power, the present stagnation could be ended if a subsidization mechanism is agreed at the climate negotiations. Such a subsidisation mechanism would be a significant drain on precious resources which would be much better spent on the real solutions.

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