A Discussion of Nuclear Power as a Solution to Global Warming

Introduction

The nuclear industry is in near-terminal decline world-wide, following its failure to establish itself as a clean, cheap, safe or reliable energy source. The on-going crisis in nuclear waste management, in safety and in economic costs have severely undermined the industry’s credibility. It is currently desperate to find a valid rationale and justification for renewed state support and funding.

There has been a marked downward world-wide trend in the fortunes of the nuclear industry throughout the last two decades. By the end of 1998, it is expected that no new reactors whatsoever will be under construction anywhere in either North America or in Western Europe. Global orders have declined from a high point in 1968, when over 40 GW of nuclear plant orders were placed, to the position today where the industry is barely able to replace the capacity of those reactors being closed.

Environmental Impact


Benefits
The greatest environmental benefit of nuclear power stations is that they do not emit Carbon Dioxide (CO2), the major greenhouse gas. Hence, switching from fossil fuels to nuclear power is claimed as the only way to cut CO2 without radically changing consumption patterns. For example, without nuclear energy, U.S. CO2 emissions would be 30 percent higher.

It has been suggested that nuclear power, which accounts for about 5% of the world's energy and 17% of its electricity - a little less than hydropower's 20% of electricity - is too small a source to be of any importance to global CO2 emissions. It is true that nuclear power, alone, cannot avert the threat of global warming, but it is probably also true that the problem of global warming cannot be tackled without reliance on nuclear power. It has been calculated that if today's 400 or so nuclear power plants were closed and the electricity generated by them were instead generated by coal-fired plants, total global CO2 emissions would increase by some 7%. The awareness is increasing among governments that the use of nuclear power is highly relevant to the efforts to prevent global warming.

The relevance of nuclear power to CO2 emissions can also be illustrated by a comparison between the United Kingdom and France. In the United Kingdom, where about 70% of electricity comes from coal burning, average CO2 emission per kWh was 0.78 kg. In France, where more than 70% of electricity comes from nuclear power, the CO2 emissions per kWh are about one tenth of the British value (0.086 kg). Moreover, according to a recent study by the French government, nuclear power will remain the cheapest centralized source of new baseload power for France into the next century.

Costs
It is often said that nuclear power is now a mature technology as it has been operating for over 40 years. Despite this, there is still no environmentally appropriate program of dealing with any form of radioactive waste. This problem is made worse on a daily basis by the continual production of radioactive waste.

Nuclear waste is produced at every stage of the nuclear fuel cycle, from uranium mining to the reprocessing of spent nuclear. Much of this waste will remain hazardous for thousands of years, leaving a deadly radioactive legacy to future generations.

At nuclear power stations, highly radioactive waste has to be regularly removed from the reactor and at most sites this ‘spent’ fuel is being stored temporarily in water-filled cooling ponds. According to independent experts, the global quantity of spent fuel produced is expected to increase from 145,000 tonnes in 1994, to 322,000 tonnes by the year 2010. Whilst a variety of disposal methods have been under discussion for decades, there is still no demonstrated method for isolating nuclear waste from the environment for adequate time periods.

In addition to radioactive waste, the danger of meltdowns of nuclear plants is one of the greatest costs of nuclear energy. The problems of reactor safety are three fold:

(a)Reactors approaching the end of their design lives are a recognised hazard which is not being addressed.

(b)The poor safety management appears to be endemic in some national industries and an ongoing problem.

(c)The safety of current and future reactor designs cannot be demonstrated to the necessary degree given the serious consequences of a nuclear accident.

Around the world nuclear power plants are getting older, both in the East and in the West. Although much public and political concern has centred on the hazards of the older Soviet-designed reactors, experience has shown that problems and signs of aging are also occurring in western reactors. By the turn of the century some 200 reactors will have been in operations for 20 years. Half of these will be over 25 years old. The safety problems posed by aging reactors are being largely ignored by the industry. Given the enormous consequences of nuclear accidents such as Chernobyl, great attention must be devoted to the aging process of nuclear reactors. Unfortunately, instead of placing more stringent requirements on older plant, safety is often cut back to permit continued operation (Meyer, N. (1996) Aging in Nuclear Power Plants. April 1996).

In the former Soviet Union at least 9 million people have been effected by the Chernobyl disaster; 2.5 million in Belarus; 3.5 million in Ukraine; and 3 million in Russia. In total over 160,000 km2 of land is contaminated in the three republics. (Strengthening of the Co-ordination of Humanitarian and Disaster Relief Assistance of the United Nations, Report of the Secretary General of the United Nations, November 1995)

Although the nuclear industry continues to refute evidence on the widespread health effects and prevalence of diseases resulting from Chernobyl, it is now widely accepted that the accident has resulted in a massive increase in thyroid cancers in those three countries. The President of the European Thyroid Cancer Association, Dilwyn Williams, has stated that thousands of children exposed to radiation will contract thyroid cancer in the next 30 years. (Terrifying outlook for Chernobyl's babies. New Scientist, 2nd December 1995)

The effect of the global increase in the number of aging reactors is a serious increase in global health risk from nuclear power plants.

The current round of reactor closures in Canada demonstrates that the managerial and procedural inadequacies that lead to Chernobyl are also very much alive in western, OECD nuclear industries. A commissioned "brutally honest" report by Carl Andognini, a U.S. nuclear expert, resulted in the closure of seven nuclear reactors in Ontario on safety grounds. Andognini stated that, "this is not a technology problem. It's a managerial problem", with lack of staff training, minimally acceptable radiation protection and minimal emergency preparedness cited. (Crone, G. & Brennan, R. (1997) Ontario Hydro knew how to build nuclear reactors but it didn't know how to run them. Southam News, Toronto, Canada)

Economic Impact


Benefits
The greatest benefit of nuclear power to the Australian economy is the resultant demand for uranium. Australia is home to the largest deposits of uranium in the world and uranium mining is a billion dollar industry. Australia’s economy would suffer greatly if the demand for uranium decreased substantially due to a move away from the use of nuclear power.

Another economic benefit is the incredible efficiency of nuclear power compared to other energy sources. For example, a coal-fueled plant of 1000 MW(e) will require about 7000 tonnes of coal per day - i.e. about five train loads. A nuclear plant of the same electric capacity will use some 80 kilograms of uranium per day. The coal plant will annually emit some 9000 tonnes of sodium dioxide gas, 4500 tonnes of nitrogen oxide, and no less than 6.5 million tonnes of carbon dioxide. It will also produce some 400 tonnes of various toxic heavy metals in the ash. The nuclear plant will produce 30 tonnes of highly radioactive spent fuel per year.

Costs
According to the American business magazine ‘Forbes’, "The failure of the US nuclear power program ranks as the largest managerial disaster in business history". (J. Cook (1985). Nuclear Follies. Forbes, 11th Feb, 1985)

Early hopes of cheap nuclear energy were based on an expectation that whilst nuclear power stations would be more expensive than fossil fuel plants, their running and maintenance costs would be extremely low. Experience has shown that the early optimism was totally misplaced.

The cost of nuclear activity at all levels has exceeded those early predictions. In many countries, the construction costs of nuclear power plants have proved to be much higher than first expected. Plants have taken longer to build and there have been many unforeseen technical problems. Running costs have also been much less predictable than was first thought. The costs of increased safety demands and regular equipment breakdowns have been compounded by the expensive question of how to deal with the nuclear waste. In addition, the predicted cost of decommissioning power stations has also escalated. (Pasqualetti, M. J (1990) Ed.. Nuclear Decommissioning and Society, Public Links To A New Technology, Edited by Martin J Pasqualetti, Published by Routledge, 1990)


Figure 1: The declining role of nuclear power (Nuclear Engineering International Handbook, 1994).

In the United States no new nuclear power stations have been ordered since 1978. This has happened in a country which launched the Pressurised Water Reactor design and which houses many more nuclear reactors than any other country. Construction and operating costs have risen so dramatically, especially since the extra safety demands made after the accident at Three Mile Island, that some companies have faced bankruptcy. (Nuclear Power Shut It Down Volume 1, The Ecologist)

In the United Kingdom, after a review of the privatisation of the nuclear power industry, the government dismissed the industry’s demands for public funding to build new reactors to combat global warming. Six months later, British Energy cancelled two proposed stations, leaving the UK for the first time in over 40 years with no plans for new nuclear power stations.

In addition to compensating for the industry’s optimistic assumptions, the true cost of any power source must include external costs. Such costs do not appear on the operators’ balance sheets, however, and are therefore hidden.


Figure 2 : External costs of fossil, nuclear and renewable power, US cents/kWh (Pearce, 1992).


Figure 3 : Total cost of fossil, nuclear and renewable energy, UScents/kWh (Pearce, 1992 and Grubb & Vigotti, 1997).

The external costs of nuclear power include the cost of environmental damage, the effect on human health and society following an accident, damage to human health and the environment during routine operation of nuclear facilities and also long term problems associated with nuclear waste and decommissioning of nuclear facilities. ‘Externalities’ that lend themselves to monetary quantification include economic effects, employment, environment, environmental impacts, health effects & government subsidies, Figure 2.

When such quantifiable social costs are added to the core price of electricity, the total costs of nuclear power are extremely high. As Figure 3 shows, nuclear power no longer stays competitive against the latest generation of renewable energy.

The Future

The Intergovernmental Panel on Climate Change (IPCC), several hundred scientists and contributors, all recognised internationally as experts in their field, was brought together by the UN and World Meteorological Society to assess climate change. The IPCC has considered several scenarios into climate change mitigation responses, of which one includes the global expansion of nuclear power.

In 1995 the IPCC published a study which reported as follows (IPCC working group II (1995) Impacts, Adaptions and Mitigation of Climate Change: Scientific-Technical Analyses. Climate Change 1995 IPCC working group II) :



The IPCC developed the above scenario using projections derived from penetration curves in each region, based upon the present status and trends of national nuclear programs. The asymptotic share of nuclear power in electricity generation was estimated by region, taking into account the availability of alternative energy sources and the size of the grid-connected electricity network.

Under this set of assumptions and constraints, the installed nuclear capacity would grow from the present 330 GW to about 3,300 GW in 2100. This assumes a tenfold increase in the number of nuclear reactors over the next century. With this increase in the number of reactors operating, there would also be a massive increase in the amount of spent nuclear fuel and radioactive waste generated. The IPCC calculates that if this scenario is followed, it would lead to some 6.3 million tons of accumulated spent fuel by 2100, using the technology currently available.

The IPCC also analysed the possibility of reprocessing i.e. the process of chemically separating out plutonium from the spent nuclear fuel, for use in Fast Breeder Reactors, which burn plutonium instead of uranium as fuel. The accumulated volumes of high level nuclear waste to be disposed of would be some 200,000 cubic metres by 2100. Between 0.1 - 3 million kg/yr of plutonium would be generated, depending on the mix of technologies used, resulting in a plutonium inventory of between 50-100 million kg. The security threat that such massive amounts of plutonium would pose would be colossal. A nuclear bomb powerful enough to destroy a city requires a mere 10 kg of plutonium.

If the majority of spent fuel was to be reprocessed, and if for example 3 million kg/yr of plutonium was to be generated, global plutonium production would follow the pattern below:


Figure 4 : Plutonium production per year by region based on IPCC scenario.

Alternative Solutions

Since the oil crisis of the 1970’s, several ‘new’ forms of electrical power generation have emerged, and of these a handful are now considered ‘mature’ and ‘bankable’. This means that they are considered to be reliable and durable power production systems and are therefore able to secure private investment. Many of these technologies are therefore coming into main-stream use, with hundreds of megawatts installed each year. On the other hand it has become clear that nuclear power is not bankable. In particular the World Bank states (World Bank (1992). Guideline for Environmental Assessment of Energy and Industry Projects. World Bank technical paper No. 154./1992. Environmental Assessment Sourcebook, Vol III) :

"Bank lending for the energy sector requires a review of sector investments, institutions and policies. Nuclear plants in the power sector would not be economic; they are large white elephants".

Furthermore the Asian Development Bank writes (Asian Development Bank (1995) Bank Policy for Energy Sector. May 1995) :

“The Bank is very much aware of this background [on nuclear power] and has not been involved in the financing of nuclear power generation projects in the Developing Member Countries due to a number of concerns. These concerns include issues related to transfer of nuclear technology, procurement limitations, proliferation risks, fuel availability and procurement constraints, and environmental and safety aspects. The Bank will maintain its policy of non involvement in the financing of nuclear power generation".

Wind power, hydro electric, photovoltaic, land-fill gas and biomass all derive their energy from the sun, whether by direct conversion using solar cells, the global thermal currents created by heating, potential energy imparted through the water cycle or through the energy absorbed by plant life which is released with decomposition. These energy forms may be taken as sustainable.

In the late 1990’s, the renewable industries have been aggressively competitive. The following table shows the competitiveness of renewable energy technologies, even ignoring the environmental costs associated with fossil and nuclear generated electricity.


Figure 5 : Commercial renewables against proposed and actual nuclear costs (NEPI: Nuclear Energy Policy Issues Proposal for Sizewell C, 1994; NUFFO figures from Grubb & Vigotti, 1997).

The following is a brief discussion of several energy source alternatives:

Wind power
The wind as a source of energy has been used for 4,000 years. From its early start in the pumping water in Persia, it has become one of the most successful of the new renewable energy industries , both in terms of turnover and also newly installed capacity. The technology has changed from slow multi-blade rotors such as the American farm wind mill to sleek, three bladed rotors which are optimised for grid- connected electricity generation.

In the same way that an aeroplane plane wing is able to create lift by moving forward through the air, the wind turbine also uses a lift force on its blades to turn the rotor around its circular path and so extract energy from the flow of air. Machines of 1.5MW are now available off the shelf and wind farm installations totalled 6,500MW in 1996. It is anticipated that large wind farms will increasingly be placed off-shore where the higher cost of installation is overcome by cleaner and more consistent winds, while visual, noise and land-use limitations are avoided.

Solar Photovoltaic
Each day the sun pours 15,000 times more energy upon the earth than we generate ourselves from fossil and nuclear sources. Photovoltaic systems are already a billion dollar business, with over 80MWp of solar cell capacity shipped in 1996 (US$1.12 billion). A PV cell is made from a sliver of silicon which is doped with small amounts of other elements. These impurities are arranged to give it a net excess of electrons on one surface and net deficit of electrons on the other surfaces. Since one side is more negatively charged than the other, an electric field is created. Nothing moves under the action of this field until a particle of light, a photon, kicks an electron out of its place in the crystal of silicon. The liberated electron can move and the space it leaves allows movement of electrons between the two sides of the wafer, Hence a current flows through a circuit joining the two surfaces. The technology is very similar to that of transistors which drive almost all modern electronics . Much younger in their development, PV systems continue to drop in price. The bulk of the current industry is in stand alone power systems that require no maintenance, though in the later part of the 1990s they are now being adopted as roofing materials for grid connected generation.

Solar Thermal
Solar thermal systems use the same approach as a child with a pocket lens burning a hole in a piece of paper. The lens is replaced by a series of mirrors and the piece of paper is replaced by the a tube of water. The tube acts as a boiler. For power generation the intensity of heat the boiler is increased and the resulting steam is used to drive a steam turbine and generator. Though solar thermal power stations are not yet mainstream the most popular use of solar thermal energy is for providing hot water. It is already popular in a number of countries including China, and in certain other countries a solar hot water heater is now a standard building requirement.

Hydro-Electric Power
Environmentally sound hydro-electricity has come to mean run-of-river turbines, or installations that make use of the flow from existing dams. The vision of thousand megawatt hydro-electric power stations as an ample source of green power has undergone substantial revaluation in the nineties. The public protests at the destruction of river systems through flooding have now been joined by a recognition that the decomposition of the submerged forests and vegetation results in the production of large quantities of methane (a considerably more potent greenhouse gas than CO2) and the loss of a carbon sink.

Biomass
Biomass simply refers to organic material that may be burned to produce energy, such as wood. If the rate of consumption is equal to the rate of renewal of the supply then the cycle is sustainable. For power generation the most common form of sustainable biomass is the combustion of timber waste in managed forests.

Variations include the use of sugar crops to provide alcohol as an automotive fuel as is used by over 10 million cars in Brazil, the use of organic waste in dedicated digesters to produce methane or biogas and the extraction of methane in sewerage systems that not only power the sewerage plants but sell excess energy into the grid. It should be noted that toxic additives such as pesticides in organic matter result in the production of toxic gases unless appropriate emission controls are applied.

Land-fill Gas
Decomposing organic matter produces methane. Household waste has traditionally been rich in organic waste and so the land-fills where the waste is deposited provide a concentrated supply of methane for two or three decades. By placing a cap on the land fill to seal it, then sinking gas extracting tubes into the area, the methane is drawn off as it is produced and combusted in 1MW engines adapted for the task. As with biomass, emission controls are required to avoid the production of toxic gases. Typical land-fills provide between 2MW and 5MW of power. As with biomass, land-fill gas is carbon dioxide neutral as it essentially uses crop waste. Land-fill gas is currently one of the cheapest of the renewables, with costs often less than 5 US cents per KWh. However, as recycling - including the composting of household waste - becomes a more productive use of organic waste, the output of future landfills will deteriorate. For the next three decades or so land-fill gas will provide a very cheap form of power and a transition supply as the other technologies further develop.

Conclusion

In terms of the economy and the environment, it is clear that the costs of nuclear power outweigh the benefits. A number of more environmentally friendly and economically sound alternatives to nuclear power exist as discussed above. Until solutions to problems such as radioactive waste and meltdowns are found, I feel that nuclear power should not be considered as a possible energy solution for today’s world but instead we should turn to other sources. However, this does not necessarily mean the decommissioning of nuclear power plants due to the dangers of such a task and the enormous economic cost of trying to replace the large number of nuclear plants in existence. Instead I feel that no more nuclear power plants should be produced especially when the range of alternatives are considered.