Nuclear Energy and
Climate Chang
Climate change: a lifeline for nuclear power?
In recent years the balance of evidence has confirmed that our planet is becoming warmer due to the emission of greenhouse gases by human activities. Approximately half of these greenhouse gases are emitted by the energy sector. In order to avert catastrophic climate change we urgently need to reduce greenhouse gas emissions.
However, the energy demands of the world's population are still growing at an alarming rate. 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.
The nuclear power industry is engaged in a huge PR campaign to convince the public and decision-makers that nuclear power is the answer to the climate change problem. By promoting itself as the saviour of the environment the failing industry hopes to give itself a new lease of life. However, their arguments are based on a number of myths, namely that:
When nuclear power was first introduced to the world in the middle of the twentieth century, it was promoted as a cheap and limitless energy source that could satisfy the world's growing energy needs.
In 1954 Lewis Strauss, at that time the head of the US Atomic Energy Commission, promised that nuclear power plants would provide electricity "too cheap to meter".
In 1974, the International Atomic Energy Agency (IAEA) forecast that there would be up to 4,450 reactors of 1,000 Megawatt (MW) in operation in the world by the year 2000. Uranium would rapidly become scarce but plutonium-fuelled fast breeder reactors would provide endless amounts of cheap electricity (WWF, 2000).
The situation today is a far cry from these early predictions. At present there are 442 nuclear reactors in operation around the world: less than 10% the number predicted by the IAEA thirty years ago (Scheer, 2004). These reactors provide approximately 16% of the world's electricity (Slingerland et al, 2004), and just 2.5% of the world's formal energy demand (WWF, 2000; Hodgson & Maignac, 2001).
At the end of 2002 only 32 reactors were listed as being under construction (Slingerland et al, 2004). A large number of these have been officially listed as "under construction" for over 15 years and will probably never be completed. (Atom's Amok, 2004). In the United States, there has not been a successful reactor order in more than 30 years. The last one ordered was the Palo Verde reactor, in October 1973.
Climate change is widely acknowledged as being one of the most pressing issues for the global community. In 2001 the United Nations Intergovernmental Panel on Climate Change (IPCC) published its most recent overview report on the issue. This report stressed that there is ever more convincing evidence to suggest that most of the warming of the earth must be directly attributed to human activities, namely the emission of greenhouse gases by burning fossil fuels (oil, coal and gas) for energy production.
Mechanics
Greenhouse gases are naturally found in the atmosphere and trap part of the sun's heat in the lower atmosphere. This process keeps our planet warm and makes life on earth possible. If the atmosphere were devoid of these gases the average global temperature would be approximately 33°C lower than it is today (Barry and Chorley, 1992). However, due to human activities, the concentrations of greenhouse gases in the atmosphere are increasing unnaturally. This results in the trapping of too much heat, leading to a rise in global temperature.
Rising temperatures and sea-levels
Furthermore, the IPCC report suggests that the temperature rise of the 20th century is very likely the cause of the detected sea-level rise over that period (IPCC, 2001a). The warming up of the seas leads to an increase in the water volume, which makes the sea level rise. What are the effects of climate change?
The history of the earth has known huge variations in average global temperatures. However, the current warming is taking place at a pace unseen for millions of years. According to the most recent findings of the IPCC, global temperatures will rise between 1.4 and 5.8°C, and sea levels by 9 to 88 cm by 2100, compared to 2000 levels (IPCC, 2001b). Whilst such a temperature rise of a few degrees may not sound particularly alarming, it should be noted that the average temperature difference between the coldest part of the last major ice-age and the present is only about 5°C (Houghton, 1994). The problem is that natural and human systems may not be able to adapt to such a pace of warming.
Effects
These changes in climate affect many aspects of the environment and society, including human health, ecosystems, agriculture and water supplies, local and global economies, sea levels and extreme weather events. Whilst some positive effects are expected (e.g. longer agricultural growing seasons in some mid-latitude countries), the negative effects will outweigh the positive even with small temperature rises. The more the temperature rises, the more negative the effects will be (IPCC, 2001b; Greenpeace, 2001).
In Europe some of the effects are already being felt. A sea-level rise of 0.8 to 3.0 mm per year over the last century is seriously felt in water management and also influences the fresh water levels. And the increase of extreme weather events (long periods of drought, extreme rains) over the last 30 years is increasingly causing economic damage e.g. in agriculture (EEA, 2004a; VROM, 2004).
Climate change agreements
In 1992 the first major international agreement on climate change, the United Nations Framework Convention on Climate Change (UNFCCC), was adopted. The UNFCCC requires that atmospheric CO2 concentrations be stabilised at a level that prevents dangerous climate change. Furthermore, this should be achieved quickly enough to allow ecosystems to adapt in a natural way, food production to continue unharmed and economies to develop sustainably. However, the convention lacked enforcement measures and specific commitments (NEA, 2002).
Kyoto
The Kyoto Protocol, adopted in 1997, built on the commitments made in the UNFCCC but went a serious step further. The protocol established concrete emissions targets for most developed countries, requiring them to reduce their collective emissions of the six most important greenhouse gases (CO2, CH4, N2O, HFK, PFK and SF6) by at least 5.2% by 2008-2012, as compared to 1990 levels. The Kyoto Protocol defines three flexible mechanisms ("flex mechs") that can be used by developed countries to assist them in meeting their emissions targets:
the clean development mechanism (CDM), joint implementation (JI) and emissions trading (NEA, 2002). With these mechanisms countries and companies can buy emission rights. The first two mechanisms allow the (co-) financing of emission saving investments. Under the CDM investments are made in countries with no obligations under the Kyoto Protocol (development countries). Under JI investments are made in countries with an obligation under the Kyoto Protocol that have 'spare' emission space (in practice Eastern European countries and Russia). A system for trade in CO2 emissions is at present developing in the European Union.
With the signature of Russia's president Putin the Kyoto Protocol has become legally binding. Although the United Stated and Australia have not signed the Kyoto Protocol, the Protocol must be considered a major step towards global climate policy.
Many in the nuclear industry have seen climate change as a 'lever' by which to revitalise the fortunes of nuclear power (IEA, 1998). Some people have described nuclear power as being "environmentally indispensable" (Ritch III, 2002), or "by far the most effective way to reduce CO2 emissions" (Hodgson & Maignac, 2001, p. 22). They assume that nuclear power emits no greenhouse gases and is low cost(NEA, 2001).
Flexible mechanisms
At present nuclear power is not included in the 'flex mechs' of the Kyoto Protocol. However these mechanisms, especially the
CDM, are seen by the nuclear industry as an opportunity to expand by gaining government grants to subsidise nuclear plants in developing countries (Groenlinks, 2000). Between now and the end of the first commitment period of the Kyoto Treaty (2008-2012), the industry will be lobbying hard to get nuclear power included in all three of the "flex mechs" after 2012 (NEA, 2002).
Growing concerns about climate change seem to make the nuclear energy option appear more attractive to some high level officials. Some countries already see a new commitment period as another chance to make carbon finance available to fund nuclear power. In October 2004, the Japanese Ministry of Economy, Trade and Industry (MITI) published a report on future climate actions that included a recommendation to make nuclear power eligible for the
CDM(METI, 2004). In November 2004 the head of the Italian Climate Change office called for the use of nuclear power in the CDM to be "look[ed] at" (Point Carbon, 2004).
In 2002, the then EU Research Commissioner Philippe Busquin stated that nuclear energy could greatly contribute to meeting Kyoto Protocol requirements. In the same year the UK government chief scientific advisor, Prof. D. King, argued strongly that the UK must build new nuclear power stations and that the radioactive waste problem is "a legacy of the past" (N-Base, 2002). Earlier this year, British Prime Minister Tony Blair stated that the UK has not ruled out nuclear power as a means of fighting climate change (WNA, 2004b).
Even if this were the case, switching the entire world's electricity production to nuclear would still not solve the problem because the production of electricity is only one of many human activities that release greenhouse gases.
Other sources of greenhouse gases include transport and heating, agriculture, the production of cement and deforestation. The CO2 released worldwide through electricity production accounts for only 9% of total annual human greenhouse gas emissions (UIC, 2001b).
This section discusses:
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.
How much greenhouse gas is emitted compared to the amount of electricity produced?
In order to establish the magnitude of these emissions compared to emissions from other forms of electricity production, it is necessary to carry out comparative lifecycle assessment of the various energy supply options. In these assessments the total emissions over the whole lifecycle are added together and divided by the total electricity produced over the lifetime of the power plant: the result shows the total greenhouse gas emissions per kWh electricity.
A number of lifecycle assessments for various electricity production processes have been carried out in the past. One of the most comprehensive of these was carried out by the Öko Institute in Germany. It is based on 10 years of research in the GEMIS (Global Emission Model for Integrated Systems) database. A number of the results are shown in the following table.
| Generation Method | Greenhouse Gas Emissions (CO2-eq. /kWh) |
| Wind | 20 |
| Hydroelectric | 33 |
| Nuclear | 35 |
| Gas Combined Cycle Ca. | 400 |
| Coal Ca. | 1000 |
|
Table 1: Greenhouse gas emissions per generation method in Germany (Öko Institute, 1997).
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 (IAE, 1994; CRIEPI, 1995). A more recent study by Storm van Leeuwen & Smith (2004) estimated the difference in emissions between nuclear and gas power plants to be much smaller than the assessments described above. 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% (Canadian Nuclear, 2002, cited in Slingerland et al, 2004).
Can we reduce the emissions of the public energy sector (electricity and combined heat/ electricity) by replacing fossil fuels with nuclear power on a large scale? And if so, how many new power plants would we need?
Makhijani (2002) estimates that, in order to produce a noticeable reduction in global CO2 emissions, it would be necessary to build 2000 large new nuclear reactors of 1000 MW each. The U.S. National Commission on Energy estimates that U.S. reactors would have to double or triple over the next 30-50 years. This means about 300-400 new reactors, including those to replace reactors which will be retiring during that period (National Commission on Energy, 2004).
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 (EarthTrends, 2003).
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.
Society does not just require energy in the form of electricity: heat is also essential. In the average French household for example, two thirds of the energy used is heat and one-third is electricity (WWF, 2000). When fossil fuels are burnt to produce electricity, a by-product of the process is heat.
Traditionally this heat energy has been lost as waste and therefore the efficiency of fossil fuel burning power plants has been low. However, in the last few decades huge advances have been made in fossil fuel cogeneration plants where most of this 'waste heat' is recovered and used in industrial heating or urban heating systems. The efficiency in these plants can reach as high as 90%, compared to 35-55% in conventional plants (Field, 2000; WWF, 2000).
The Öko Institute has calculated the total greenhouse gas emissions of producing 1kWh electricity and 2kWh heat by various energy systems.
A natural-gas fired cogeneration plant typically generates about one-third electricity and two-thirds heat, so all of the emissions in this system would stem from the cogeneration plant.
In the case of a conventional nuclear plant power, the heat would have to be generated from another source: the Öko study chose an oil-fired central heating system. (Oil was chosen because the associated emissions fall between those of coal and gas.) The total emissions in this case would be as for 1kWh electricity generation in the nuclear plant, and 2 kWh heat production by the oil-fired central heating system. The results reveal that the total emissions from the gas cogeneration plant are of the same order of magnitude as those produced in the nuclear + oil example.
Therefore, if we were to replace older fossil-fuel burning power stations with new cogeneration systems, for the same amount of electricity and heat generation the total greenhouse gas emissions would be similar to those in a system based on electricity from nuclear power and heating from fossil fuels.
A number of nuclear cogeneration power plants have been built in Russia, Slovakia, Switzerland and Canada amongst others (Federation of Electric Power Companies of Japan, 2000). However, these are the exception rather than the rule.
While nuclear cogeneration is technically feasible, there is much less experience with this method than with fossil-fuel powered cogeneration plants mainly because nuclear power plants are built far from urban areas. Therefore the transport of the heat from the nuclear power station to the consumer would lead to a lot of heat loss.
In 2003 France generated 75% of its electricity in nuclear power plants. The nuclear industry likes to use France as a shining example of the advantages of nuclear power. However, France's greenhouse gas emissions in 2000 were still increasing, largely because it has lost control of energy consumption in other sectors, e.g. transport.
Furthermore, studies of future energy scenarios carried out by the French Government Central Planning Agency show no evident correlation between CO2 emissions and nuclear power.
In fact, the scenario with the lowest emissions was the one in which the growth in demand was minimised, not the one with the greatest use of nuclear power (Boisson, 1998 & Charpin et al., 2000). In another study, a comparison was made between the results of investments in wind energy and the same amount of investment in nuclear energy. The results were clearly favourable for wind energy. With the same investment much more energy could be generated with wind. Moreover, with investments in wind energy more new jobs were generated than with investments in nuclear energy (Bonduelle & Levevre, 2003).
Just as with fossil fuel, the use of uranium as fuel is limited by its availability. Uranium is a finite resource. Although we are often told by the nuclear industry that uranium is a "plentiful commodity" (Ritch III, 2002), an examination of the data reveals that this is not the case.
How large are the planet's uranium reserves?
According to the most recent figures of the Nuclear Energy Agency (NEA) and the International Atomic Energy Agency (IAEA) on global uranium reserves, the total known recoverable reserves amount to 3,5 million tonnes: this refers to reasonably assured reserves and estimated additional reserves which can be extracted at a cost of less than $80/kg (NEA & IAEA, 2004).
Given that the current use of uranium is in the order of 67,000 tonnes per year, this would give us enough uranium for about 50 years(WISE, 2003; NEA-IAEA, 2004; WNA, 2004c). Of course, the total reserves of uranium are much greater than this; NEA and IAEA estimate the total of all conventional reserves to be in the order of 14,4 million tonnes. But not only are these reserves very expensive to mine, and therefore not economically viable, the grades of usable uranium are too low for net electricity production. Large parts of the presently quoted reserves (about half) are marginal already. This is the case in Namibia, South Africa, Kazakhstan and with the Olympic Dam mine in Australia.
As pointed out by advocates of nuclear power, there are also vast amounts of uranium in unconventional sources. For example uranium is found in ocean water, but at a concentration of 0.0000002% (Storm van Leeuwen & Smith, 2004). The costs of extracting this uranium for use in nuclear power generation would be huge. Furthermore, the extraction and enrichment of this uranium would require more energy than could be produced with it.
If we would decide to replace all electricity generated by burning fossil fuel with electricity from nuclear power today, there would be enough economically viable uranium to fuel the reactors for between 3 and 4 years (O'Rourke, 2004; Storm van Leeuwen & Smith, 2004). Even if we were only to double world usage of nuclear energy, the life span of uranium reserves would be just 25 years. Therefore any potential benefits to the climate are extremely temporary.
The economics of nuclear power
This section addresses two important questions:
In the 1970s nuclear power cost half as much as electricity from coal burning: by 1990 nuclear power cost twice as much as electricity from coal burning (Slingerland et al, 2004). Today the costs of nuclear power are estimated to be, on average, between 2 and 4 times more expensive than electricity generated by burning fossil fuels, about $0.05-0.07/kWh.
Compared with some modern renewable energy sources, nuclear power has mixed fortunes: for example it is more expensive than wind, about the same price as hydroelectric power and cogeneration with gasified wood, and cheaper than solar energy using photovoltaic (PV) cells (Öko Institute, 1997).
However, whilst the costs of nuclear power are rising, those associated with renewable energy sources are falling rapidly as they are relatively new and rapid progress is currently being made in reducing costs and increasing efficiency. In the case of nuclear power the costs are rising and are likely to continue rising for the foreseeable future. This is partly because the nuclear industry has been heavily subsidised by governments in the past meaning that some of the costs have been excluded from the price, but have been paid for by the taxpayer. We all pay for the costs of nuclear energy. Examples include:
- Decommissioning: so far very few nuclear installations have been decommissioned but in the coming years many plants will reach the end of their lifetimes and will be shut down. Experience in the USA and elsewhere has shown thatdecommissioning is an extremely expensive process. For example, the decommissioning of the Yankee Rowe nuclear reactor in Massachusetts was expected to cost $120 million but actually cost about $450 million. The cost of decommissioning all of the reactors in the US could be as high as $33 billion (GAO, 2003). Costs are this high because a large part of the building is radioactive and can only be demolished by robots. These radioactive materials must also be removed and stored under secured circumstances.
- Liability: the Price-Anderson Act in the USA limits the nuclear industry's liability in the case of an accident to $9.1 billion, less than 2% of the $560 billion that could be caused in damages by a serious nuclear disaster, according to American federal research into the consequences of the Three Mile Island accident in 1979. The other 98% of the costs will have to be paid for by the government. If the nuclear industry itself had to take full financial responsibility for potential nuclear disasters, the costs of insurance would be huge and the cost of nuclear power would also be much higher (Mechtenberg-Berrigan, 2003). The Paris Convention on Third Party Liability sets the maximum economic liability of nuclear operators in 15 European countries. Although the maximum operator liability was revised upwards in 2004 to €700 million (NEA, 2004), this amount would be truly insignificant in the event of a nuclear disaster.
The market itself provides evidence of nuclear power's lack of financially viability. Since the liberalisation and privatisation of the energy markets in the UK, the full costs of nuclear power have been more exposed. Companies have not been eager to invest in this energy source as it cannot exist in a competitive market without government subsidies (FOE, 1998). Even in France, where nuclear power accounts for 75% of total electricity production, it has been admitted that nuclear power is far more expensive than electricity from efficient fossil fuel burning power plants (Makhijani, 2002).
With regards to climate change it is also important to know the cost of reducing greenhouse gas emissions associated with various options, e.g. different energy sources, different levels of end-user efficiency etc. These costs are commonly referred to as the CO2 abatement costs. These are the costs of reducing greenhouse gas emissions by a given amount (e.g. 1 tonne) in comparison to a given reference option, usually coal.
The Öko Institute has calculated the abatement costs per tonne of CO2 reduction in relation to a coal-fired power station in Germany. The results are shown in the graph below.
CO2 abatement costs for various electricity systems (adapted from Öko Institute, 1997)
As can be seen, CO2 reductions can be made at negative costs by employing combined cycle gas turbine cogeneration, wind, cogeneration with gasified wood and simple energy efficiency. Nuclear power has positive abatement costs, in about the same order of magnitude as new hydropower, gas cogeneration, advanced energy efficiency, and biogas cogeneration. Hence, a variety of renewable and fossil fuel efficient alternatives are available which are economically more viable than nuclear power in terms of greenhouse gas abatement.
Electricity generation accounts for just 9% of annual human greenhouse gas emissions. Ways must be found to reduce emissions from the whole of the energy sector.
This section briefly outlines a few of the alternatives by which the world can satisfy its energy needs in an economically and environmentally sustainable way.
Sustainable is above all efficient
There are hundreds of ways to reduce greenhouse gas emissions within the energy sector. A few examples are listed below but the list is by no means exhaustive:
- Renewable energy (wind, solar, geothermal, hydro, tidal, biomass etc.);
- Cleaner use of fossil fuels;
- Increased taxation on CO2 emissions;
- CO2 sequestration (storing CO2 produced in power stations);
- Increased energy efficiency.
Numerous studies have shown that the single most effective way to reduce emissions is to reduce energy demand (Marignac & Schneider, 2001). A lot of energy could already be saved with the design of smarter consumer electronics, or with less wasteful ways to regulate the temperatures of our building. This may seem obvious but unfortunately it is all too often forgotten in policymaking. Unfortunately this seems to be the case in the largest energy consuming country in the world, the USA. The views of the current administration on energy policy are typified in the following quote from Vice President Dick Cheney:
"Conservation may be a sign of personal virtue, but it is not a sufficient basis for a sound, comprehensive energy policy." (Cited in Cunningham et al, 2003 p. 496)
China is set to overtake the US (at 21%) as the biggest producer of greenhouse gases by 2025 unless current trends are modified (WWF, 2004). Although a major enlargement program for nuclear energy has got underway, this will not provide any solution to China's contribution to climate change. China has vast cheap coal and gas resources and it is an illusion to imagine that nuclear developments will prevent China from using its coal. The key challenge will be to slow down the enormous increases on the demand side (Schneider & Froggatt, 2004) by shifting towards using renewable energy, such as solar or wind power, and more efficiency in energy consumption.
Can sustainable energy supply our needs?
The whole of society's energy demands amount to less than 0.1% of the energy we receive from the sun each year . So far there are only limited places where we can harness this solar energy in an effective way but this gives an indication of the vast potential of renewable energy sources. Chances for renewable energy will increase substantially in a supportive economic climate and when governments set ambitious but realistic targets. In some countries, such as Germany, the scientific community operates in important studies with an ambitious target of 46% renewable energy sources by 2050 (Johansson et. al, 2004).
Renewable energy sources have multiple benefits. Not only is their use free from greenhouse gas emissions but they can also increase diversity in the energy market. Thereby they will reduce dependence on specific energy sources and so increase security of supply. They can provide long-term sustainability of our energy supply. And because of their small-scale applicability, they can be used in rural areas of less developed countries that are not connected to gas and electricity networks.
In the medium term it is possible to supply all of the world's energy needs through renewable sources based on current technology (i.e. not including the further developments to be made in the future). This scenario has been depicted in three separate studies, compiled by The Union of Concerned Scientists in the USA (1978); The International Institute for Applied Systems Analysis for Europe (1981); Enquete Commission of the German Bundestag (2002). Whilst none of these studies have ever been seriously refuted, they have all been largely ignored by conventional experts (Scheer, 2004).
The technology is available to provide our energy needs through renewable sources and thereby to make huge reductions in our greenhouse gas emissions. However, in the past new energy systems have not been fully implemented due to the supposed high financial costs. It now turns out that these costs are not so high.
The costs of alternative energy options
Despite the commonly heard arguments that alternative energy sources and energy saving technology are not economically viable, the majority of studies show that this is not actually the case. In 1997, a report issued by the United States Department of Energy (DOE) stated that CO2 emissions in the USA could be brought back to 1990 levels by 2010 at no added cost by increasing energy efficiency and decreasing demand (FOE, 1998). A World Energy Council (WEC) report in the same year confirmed thatincreased energy efficiency is the biggest, most immediate and cost-effective way to reduce greenhouse gas emission (WWF, 2000). Furthermore, the costs of renewable energy sources are falling very rapidly: in the last 10 years the cost per kWh of electricity from wind turbines fell by 50%, and that from photovoltaic cells fell by 30% (NEA, 2001). Costs of renewable energy sources are expected to become lower as more research is carried out and more experience is gained with these techniques.
The most interesting point to note here is that the costs of renewable energy sources are falling whilst the costs of nuclear power are rising, despite the fact that nuclear power has been hugely subsidised over the last half century. Estimates show that to date the nuclear industry has received around $1 trillion in state support, compared to just $50 billion for renewable energy (Scheer, 2004). If these huge investments had been made in renewable energy the total energy production from these sources would today be huge.
Given the fact that nuclear power can only temporarily and partially contribute to reduce greenhouse gas emissions it would be very inefficient to invest huge sums in nuclear development whilst investments in truly sustainable and environmentally friendly energy alternatives are much more rewarding.
Other problems associated with nuclear power
Nuclear power is very expensive and moreover, many alternatives are available which can reduce CO2 emissions far more effectively, for infinite time periods, and at far lower costs.
However, some people argue that climate change is such an important issue that we must employ all available methods to reduce greenhouse gas emissions, no matter what the cost.
There are so many other serious problems associated with nuclear power that any minor and temporary benefits are of tiny significance compared to the problems. These problems have existed since the introduction of nuclear power and are still not resolved. The chance that they will be solved within a reasonable time becomes more and more unlikely.
In this section we will highlight the four major problems:
One of the most serious and persistent problems of nuclear power is what to do with radioactive waste. Supporters argue that radioactive waste is actually not a major problem since the quantities are small. Whilst this may be true in relation to coal-fired power plants, there are still huge amounts of waste created during the nuclear process. In factthe production of 1,000 tons of uranium fuel typically generates 100,000 tons of tailings and 3.5 million litres of liquid waste(Cunningham et al, 2003).
The amount of sludge produced is nearly the same as that of the ore milled. At a grade of 0.1% uranium, 99.9% of the material is left over. As long-lived decay products such as thorium-230 and radium-226 are not removed, the sludge contains 85% of the initial radioactivity of the ore. In addition, the sludge contains heavy metals and other contaminants such as arsenic, as well as chemical reagents used during the milling process.
Still, the volume of waste is not the main problem associated with nuclear waste. The main problem is that high-level waste remains dangerously radioactive for up to 240,000 years (Greenpeace, 2004). After half a century of research there are still no satisfactory solutions to this problem.
The most commonly suggested solution is to build underground waste repositories for long-term storage. In 1987, the U.S. Department of Energy announced plans to build such a repository at Yucca Mountain in Nevada. According to the plan, high-level radioactive waste will be buried deep in the ground where it will hopefully remain unexposed to groundwater and unaffected by earthquakes (Cunningham et al, 2003).
On a timescale of hundreds of thousands of years, however, it is impossible to predict whether an area will remain dry or geologically stable. Moreover the costs of monitoring and maintenance over such a timescale are unimaginable and generations for hundreds of thousands of years to come would still have to pay the cost for a few years electricity for our generation. The Yucca Mountain scheme has generated huge public outcry and it is likely that the project will never go ahead. Similar problems elsewhere in the world mean that there are currently no final repositories in operation.
In the last decades researchers have been working on the technology to reduce radioactivity and the decay time of nuclear waste, the so-called transmutation process. This has often been optimistically heralded as the future solution to the waste problem, however, there is no guarantee that research into transmutation will be successful, and if it is the financial costs will be enormous. Nuclear waste contains many different types of radioactive isotopes, which must all be partitioned separately and then transmutated separately. The aim is to decrease the decay time of the radioactivity of these isotopes. This will not be possible for all isotopes and not all isotopes can be partitioned. It will require new processing technologies and plants. At this moment only plutonium and uranium are separated in reprocessing. The application of these new techniques will require a large-scale introduction of fast breeder reactors or other new advanced reactor types, which will take billions of dollars and many decades. And it is obvious that these techniques can only be applied for future spent fuel and not for the present amount of nuclear waste (WISE, 1998). Every attempt to present it as a solution for already present waste is misleading.
Other so-called solutions that have been proposed include: disposing waste in deep ocean trenches, blasting waste into space, and leaving waste by nuclear power plants until a use for it is possibly identified in the future. This last method is now applied on a large scale.
Despite claims that the nuclear power industry has a "superb record" on safety (WNA, 2004a) and an "impeccable safety practice" (Ritch III, 2002), historical evidence provides many examples of nuclear disasters and near disasters, for example at Windscale (UK, 1957), Chelyabinsk-40 (Russia, 1957/8), Brown's Ferry (Alabama, USA, 1975), Three Mile Island (Pennsylvania, USA, 1979) and Chernobyl (Ukraine, 1986). Admittedly much progress has been made in increasing safety standards but reactors are still not inherently safe and problems are still common.
In 1995, a natrium leak in the Monju fast-breeder reactor in Japan led to its closure, and once again highlighted safety fears in the nuclear industry. More recently, in 2002, a near disaster was averted at the Davis-Besse reactor in Ohio, USA. The steel in the reactor head was found to be punctured and was within less than a quarter of an inch of causing catastrophic meltdown: in the years preceding this incident the reactor had received a near-perfect safety score (Mechtenberg- Berrigan, 2003). Due to cooling problems in France during the heat wave in the summer of 2003, engineers told the government that they could no longer guarantee the safety of the country's 58 nuclear power plants (Duval Smith, 2003). This is of particular importance as it suggests that nuclear power production will become even less safe as heat waves become more common due to climate change.
Apart from possible technical failures, the risk of human error can never be excluded. This risk will grow now that the onset of privatisation and liberalisation of the electricity market has forced nuclear operators to increase their efficiency and reduce costs. For nuclear energy, it is more difficult to reduce costs because it has high fixed costs: building costs make up about 75% of the total costs (compared, for example, with only 25% for gas). All savings must therefore come from the 25% variable costs of the electricity price, notably from efficiency increases and personnel reductions (Greenpeace & WISE, 2001). In the US significant reductions have been made with an estimated 26,000 workers leaving the industry over the last eight years. The reductions in the size of the workforce have in some cases led to concerns over safety.
One of the by-products of most nuclear reactors is plutonium-239, which can be used in nuclear weapons. The international Non Proliferation Treaty (NPT) is supposed to prevent the spread of nuclear weapons but a number of countries with nuclear capabilities, including India, Pakistan and Israel, are not party in the NPT. While most countries claim a strict delineation between nuclear power production and the military use of plutonium, it cannot be ruled out that plutonium could be used in weapons proliferation. According to the UN Climate Panel IPCC, the security threat would be "colossal" if nuclear power was used extensively to tackle climate change. Within the Non Proliferation Treaty, it is completely legal to obtain all necessary technology and material and then to withdraw from the treaty prior to deciding and announcing the wish to make nuclear weapons.
Nuclear installations could also become targets for terrorist attacks: numerous studies since the 2001 attacks on New York have found nuclear plants to be at substantial risk from terrorism (Coeytaux & Margnac, 2003; Oxford Research Group, 2003). Furthermore, radioactive material could be used by terrorists to make "dirty bombs".
In the event of a nuclear disaster the health concerns are obvious. Exposure to radioactive fallout would lead to an increased risk of genetic disorders, cancer and leukaemia. In some areas of Belarus, for example, national reports indicate that incidents of thyroid cancer in children have increased more than a hundred-fold when compared with the period before the Chernobyl accident (UN-IHA, 2004).
However, there are also health risks associated with the day-to-day production of nuclear power. Employees working in power plants are exposed to low-level radioactivity. According to a study by the University of California, based on research at the DOE/Rocketdyne nuclear facility in that American state, the risk of employee exposure to low-level radioactive waste is 6 to 8 times higher than was previously presumed (Mechtenberg-Berrigan, 2003). One should realise that there is no such thing as a safe limit. Each amount of radiation can cause serious health damage.
Conclusions
In the context of international climate change negotiations, the nuclear industry tries to depict nuclear energy as the most effective way to solve the climate problem. This claim has no basis in fact.
Nuclear energy is neither effective nor viable, it is not a sustainable source and it causes devastating problems that humanity is not able to handle.
6 key conclusions can be drawn from the analysis of nuclear power as a possible solution for the climate problem:
Nuclear energy is an inefficient and dangerous way to prevent climate change. Added to this are the problems of nuclear waste, safety risks, health risks to employees, and the risks of nuclear proliferation and terrorism.
Moreover, there are other possibilities. We have enough technical knowledge to introduce sustainable energy on a large scale and to prevent the waste of energy.
What we lack is the political will to invest in these methods of climate protection. But we will have to make a start with it, and we better do it quick. Climate change is causing too much damage already, financial as well as social and ecological. We cannot afford to ignore it.
There is still no feasible idea on how to deal with the extremely dangerous radioactive waste. It is not the volume but the level of (very long-term) danger that is the real problem with this waste. Advocates of nuclear energy point to research into techniques that should reduce the half-life of radioactivity of this waste, but the chances for success are rapidly fading. Moreover these techniques could only provide a solution for new radioactive waste, not for the existing waste. Attempts to find a safe final storage for it have failed to date.
Uranium reserves are limited and this fuel problem cannot be solved with fast breeder technology because even after decennia of research, fast breeders are a technical and economical failure. Moreover plutonium, the fuel for fast breeders, is extremely poisonous and dangerous as well as being the basis for nuclear weapons.
The costs of nuclear energy are huge, although this is not shown in the price because many costs are financed by society in the form of government subsidies. If the nuclear industry itself had to carry the costs for realistic insurance and for decommissioning then nuclear energy would be an even more expensive source of energy. And meanwhile the prices of sustainable energy are decreasing. If we have to choose where to invest our money, then governments and society should provide more means for the development of sustainable energy and energy demand reduction.
Electricity generation accounts for just 9% of total human greenhouse gas emissions, and only electricity production is possible with nuclear energy. For a solution to the climate problem, as research shows over and over again, we should look at the demand side of energy. Less energy should be wasted and sustainable sources should be developed with the utmost urgency.
When examining the various stages of the nuclear process it turns out that nuclear energy does - indirectly - generate greenhouse gases. Much less than by energy production using coal and oil, but not much less than gas and significantly more compared with electricity production from sustainable energy sources such as sun or wind. The emission factor of nuclear energy is about to rise because the grades of usable uranium in the ore will decrease in the future. Therefore more energy will be needed to mine, extract and enrich this uranium to make it usable for nuclear power generation.
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