Do we need nuclear power?

For and against

Our civilization and our standard of living depend on an adequate supply of energy. Without energy, we would not be able to heat our homes or cook our food. Long-distance travel and communication would become impossible, and our factories could no longer produce the goods that we need.

A century ago the world's energy came almost wholly from coal and "traditional" sources, such as wood, crop residues and animal dung. These are still major sources of energy, particularly in developing countries, where 2 billion people are without access to, or cannot afford, modern energy forms. Wood and dung are estimated to provide an amount of energy equivalent to 1 billion tonnes of oil each year; it is sobering to realize that this is 1.6 times more energy than is provided worldwide by nuclear power, and is about the same as the amount of energy provided by coal in Europe and the US combined (see table).

During the 20th century, the world's commercial output and population increased more rapidly than ever before, as did energy consumption, which rose more than tenfold, with a major shift towards oil and gas fuels, and to hydroelectricity and nuclear power. Most of the growth was in industrial nations, where the per capita consumption of commercial fuels is about 10 times that in the developing world.

Energy markets in the industrial countries are maturing, and may even peak and decline with continued improvements in energy efficiency. The last two centuries saw energy efficiency increase enormously - in motive power, electricity generation, lighting, in the use and conservation of heat, and in an array of other applications. There is no evidence that further gains will not be achieved in the future - for example through the use of fuel cells for transport, which could lead to a two- or threefold increase in fuel efficiency relative to that of the internal combustion engine, and through distributed sources of combined heat and power.

The situation is different in developing countries, where billions of people have hardly enough energy to survive, let alone enough to increase their living standards. If they are to achieve prosperity, their energy needs - which are doubling every 15 years - will have to be met. Moreover, their population will soon be 7-10 times greater than that of the industrial world, and (with the sad exception of several African countries) economic growth is much higher than it is for industrial nations.

If we assume that, after allowing for gains in energy efficiency, the developing world eventually uses only half of the energy per capita consumed by industrial nations today, then the world's energy consumption will still rise more than threefold. Developing nations will therefore need about 5 x 10⁶ MW of new electricity-generating capacity in the coming decades, compared with the 1 x 10⁶ MW they have today and the 2 x 10⁶ MW in the industrial nations. (Electricity generation accounts for only about one-fifth of our final energy consumption - the rest mainly being for transport and heating.)

Our common ground in debating the question "Do we need nuclear power?" is therefore the fact that the world is likely to need yet more energy, despite the immense amount of energy consumed today. The environmental problems associated with energy production and use will also need to be addressed, including local and regional pollution, and the much-discussed problem of global warming.

Peter Hodgson and Dennis Anderson

Global primary-energy consumption

Units: million tonnes of oil (toe) equivalent energy.
Sources. For 1860, 1900 and 1950: Nuclear Energy in Industry (1957 Crowther); figures converted from coal-equivalent to oil-equivalent energy by dividing by 1.5. For 2000: Statistical Review of World Energy (1999 BP Amoco), trended up to 2000; except traditional energy, from Rural Energy and Development (1996 World Bank). For primary energy, BP assumes that one tonne of oil produces 4000 kWh in a modern power station.

YES

With rising fuel costs, concerns about global warming and the growing demand from the developing world for energy, the burning question is whether the world needs nuclear power. Peter Hodgson, a nuclear physicist, says yes. Dennis Anderson, an economist, says that we should first explore the possibilities of renewables and other forms of energy.

Finding ways of satisfying our energy needs is such an urgent problem that we must consider all possible sources, and evaluate them as objectively as possible, writes Peter Hodgson. In doing so, it is useful to apply the following criteria: capacity, cost, safety, reliability and environmental effects. No source can satisfy all our energy needs, and although there are several small-scale energy sources, such as solar panels for satellites, we must focus on the major sources.

Wood was a major energy source in ancient times, and is still extensively used in developing countries. It is, however, impractical as a major energy source in developed countries as it occupies much land and adds to atmospheric pollution. Oil, meanwhile, is fast running out and is needed by the petrochemical industry. It is wasteful to burn it, which also adds to pollution. The same applies to natural gas.

Hydropower is an important source of energy, particularly as it is renewable and does not pollute the atmosphere. However, it uses up valuable land and, in any case, the number of suitable rivers is limited. It is unlikely that hydropower will provide for more than about 8% of our energy needs. Tidal power is even more limited by geographical considerations.

The remaining sources - such as wind, solar and geothermal - account for only a few per cent of the global energy consumption. In addition, some of them are unreliable (wind and solar) or intermittent (tidal) and relatively costly. And although the energy in sunshine, wind, waves and tides is enough to satisfy our needs millions of times over, the difficulty is in harnessing these sources in a usable form. Despite continued efforts, wind and solar sources contribute less than 0.5% of our energy production (see table).

Costing the Earth

This leaves only coal as a major source of energy for at least a few centuries. However, a typical coal-fired power station emits some 11 million tonnes of carbon dioxide each year, as well as 1 million tonnes of ash, 500 000 tonnes of gypsum, 29 000 tonnes of nitrous oxide, 21 000 tonnes of sludge, 16 000 tonnes of sulphur dioxide, 1000 tonnes of dust and smaller amounts of other chemicals, such as calcium, potassium, titanium and arsenic. To produce 1 gigawatt-year of electricity requires about 3.5 million tonnes of coal - and this contains over 5 tonnes of uranium. Most of the by-products are caught by filters, but a few thousand tonnes of ash escape, carrying with it a corresponding fraction of the uranium. This accounts for the radioactivity emitted by coal-fired power stations. All the gaseous waste is poured into the air we breathe, and damages our health. To continue to rely on coal could lead to widespread environmental damage and unpredictable climate change.

Can nuclear provide the energy we need? It already generates about 20% of the world's electricity, including 50% in Western Europe and 80% in France. It is reliable, having high "load factors" - typically more than 90% - with nearly all of the remaining time spent on planned maintenance. Its long-term costs are similar to those of coal. It has little harmful effect on the environment and it is safer than all other sources, apart from natural gas.

Nuclear power only differs from other energy sources in that it emits nuclear radiations. The interior of a nuclear reactor is highly radioactive, and the spent fuel has to be removed periodically for reprocessing. However, the techniques for doing this are well developed and can be carried out safely. The relatively small volumes of highly radioactive residues (nuclear waste) are first stored above ground for several decades to allow the short-lived isotopes to decay, the rest being fused into a insoluble ceramic blocks, encased in stainless-steel containers and buried far below ground in a stable geological formation.

Nuclear reactors can also be improved. While current "thermal reactors" burn only uranium-235, which accounts for just 0.7% of natural uranium, so-called "fast reactors" can burn the remaining 99.3% of the uranium. One reason why fast reactors are not used is because they are more difficult to build, but they will become more economic as uranium becomes more expensive - and could eventually take over from thermal reactors.

Before then, other reactor designs may become available. A particularly promising line of research, which is being pioneered by the Nobel-prize winning physicist Carlo Rubbia and others, is into reactors that depend on spallation neutrons from a proton accelerator. The protons hit a target of a heavy metal, such as tungsten, producing a shower of neutrons that go into a sub-critical reactor assembly. This makes the reactor go critical, thereby generating power. Such reactors are easily controlled because the reaction stops as soon as the accelerator is switched off. The neutron fluxes are also so high that the radioactive wastes can be burnt inside the reactor. These are both highly desirable environmental features. "Pebble-bed" reactors are another promising development.

In the longer term, I have high hopes that fusion energy will ultimately become available. Intensive work is in progress on several possible designs for a fusion reactor. These reactors need deuterium, which is present in water in the proportion of about one part in five thousand. The energy available from fusion reactors is therefore practically limitless.

It is indeed fortunate that, just as other major energy sources are becoming exhausted or are recognized as seriously polluting, a new energy source - nuclear power - has become available to meet our needs.

NO

I agree with the relevance of Hodgson's five criteria: capacity, cost, safety, reliability and the environment, writes Dennis Anderson. But I find he applies them unevenly toward the three main energy sources under discussion - fossil fuels, renewable energy and nuclear power - with a skew against both fossil fuels and renewable energy. Let me take fossil fuels first, since there is a moral in this for both nuclear power and renewable energy.

The United Nations "Atoms for Peace" conferences in 1955 and 1957, which set the stage for the expansion of the nuclear industry, were unambiguous about the need for nuclear power. The view was that fossil fuels would last for about 75 years and that, by the end of the 20th century, we would be faced with major energy crises unless we had nuclear power. The costs of fossil fuels would rise exponentially, while those of nuclear power would fall.

However, the opposite has happened. Fossil fuels have proven to be abundant and less expensive than nuclear power. Estimates of fossil-fuel reserves are enormous, especially of gas. "Commercially proven" reserves - those that companies have access to and declare in their assets - are a poor guide to actual reserves, which include unexplored resources and unconventional resources such as tar sands, shale oils and gas hydrates.

Estimates suggest that, at current extraction rates, we have over 200 years' supply of oil, 450 for natural gas and over 1500 for coal, the weighted average being nearly 700 years (see Rogner in further reading). Even this is an understatement, since it excludes natural-gas hydrates in the permafrost and under the ocean floors, and other sources that together are thought to amount to five times these values.

Moreover, the oil, gas and coal industries have made tremendous advances in exploration and production, and the electricity industry is steadily improving the thermal efficiency of fossil-fuel power stations. Estimates of reserves have increased more than tenfold, and costs have declined relative to those of nuclear power. Indeed, if nuclear power were to compete commercially with a natural-gas-fired power station, it would need a subsidy of more than £1bn per gigawatt.

It is, of course, easy to speak with the wisdom of hindsight, and to overlook the uncertainties and risks that the energy industry faced when nuclear-power programmes were being put in place. In the 1950s nuclear power held the promise of unlimited energy in an era when coal mining was an arduous, dangerous and unhealthy occupation for millions of workers (as it still is in China and India), when fuel shortages were common, and when coal burning in homes and industry was the source of intolerable levels of local pollution.

Better by design

Nevertheless, nuclear power has been unable to compete in terms of cost with fossil fuels, and there is no commercial interest in it outside state-run electricity sectors. The subsidies for nuclear power over the past five decades have been colossal - about a hundred times the amount we have spent on developing renewable energy, for example - and further immense subsidies will be required to deal with the legacy of nuclear wastes and the decommissioning of power stations. Indeed, following the privatization of the electricity industry in the late 1980s, the UK introduced a Non Fossil Fuel Obligation (NFFO) to support nuclear power; it injected £8bn of subsidies into the industry after it had been sold off, while another £5bn is reportedly needed to deal with the decommissioning of the Dounreay nuclear facility. The NFFO, in contrast, injected just £750m (less than 10% of the funds) into renewable energy.

It is true that nuclear power makes a sizeable contribution to energy supplies in France and the UK, and that global production grew from near zero to the equivalent of 630 million tonnes of oil (toe) per year between 1960 and 2000. But the energy obtained from biomass - albeit unsustainably gathered over large areas - also increased by almost as much, in absolute terms, as that obtained from nuclear power. The contribution of fossil fuels rose by seven times this amount, notwithstanding the predictions that they would be nearly exhausted by the year 2000.

In terms of capacity and cost, it is thus difficult to make a good case for nuclear power. Fossil fuels are more than sufficient to meet the world's energy needs economically, not least in developing countries. Will environmental concerns change this? In response to successions of clean-air acts and environmental controls introduced in industrial nations, all sectors of the energy industry have made immense strides in reducing local and regional pollution per unit of energy consumption.

With the partial exception of nitrous oxides, the development of "clean" technologies and fuels is enabling pollution per unit of energy use to be reduced by several orders of magnitude. We have seen major reductions in local and regional pollution where these technologies and practices have been introduced: reductions of smog, lead in fuels and acid deposition in Europe and the US being striking examples. The associated costs have, moreover, proved to be small compared with the overall costs of energy use, and have sometimes been negative, with the "clean" practice being more efficient than the polluting practice it displaced. Further reductions are still possible, with hybrid vehicles and fuel cells holding considerable promise. Countries taking advantage of these technological developments have been able to use more energy with less pollution and have found themselves economically better off.

The fossil-fuel industry has thus responded remarkably well to local and regional pollution problems, and there is no reason why societies cannot enjoy the benefits of using these sources while striving to improve the local and regional environment. I shall tend to the global environment later.

YES

Anderson observes that fossil fuels have proven to be abundant and less expensive than nuclear power. It is not surprising that estimates of reserves differ, because surveys are inevitably incomplete. Furthermore, the quantities available depend on how much we are prepared to pay for extraction. Relative costs are difficult to estimate because nuclear costs depend on the lifetime of the reactor, which may be as long as 60 years. A small fraction of the output invested each year easily pays for decommissioning, and reactors are now designed to facilitate this process. The cost of nuclear power relative to fossil fuels would be very different if realistic estimates of the cost of pollution and climate change were also included. In the short term, fossil fuels may appear less expensive, but it is the long term that is more important.

The Belgian government recently set up a commission to examine the options for electricity generation. Taking into account fuel costs, non-fuel costs (investment, operation and maintenance), external costs (air pollution, noise and greenhouse gases) as well as the cost of construction, grid connection and decommissioning, the commission estimated that it will cost BFr 2.34 to generate every kilowatt-hour of electricity from coal in 2010. The equivalent figures were 1.74 for gas, wind as 1.85 (seashore), 2.39 (offshore) and 3.26 (inland), but just 1.22-1.28 for nuclear power. In other words, nuclear power is not only more reliable, safer and less detrimental to the environment than the alternatives, but also substantially cheaper.

In his book The Earth Under Threat, Sir Ghillean Prance, former director of the Royal Botanical Gardens at Kew, describes in graphic detail the devastating effect on animal and plant life already attributable to climate change (see further reading). Many species, such as the golden toad in Costa Rica, have become extinct. This can be dismissed as anecdotal and lacking in statistical basis. Who cares about the golden toad? Well, I do, as I care about all threatened species.

Practical challenge

Scientists on the UN's Intergovernmental Panel for Climate Change (IPCC) have amassed impressive evidence that climate change is real. Their work indicates that in the next 100 years average global temperatures will rise by several degrees and the sea level by 50-100 cm. There are, of course, many uncertainties, but it is prudent to take climate change seriously. Many of its potentially devastating effects are directly attributable to the carbon dioxide emitted when fossil fuels are burnt. Meanwhile, impurities in fossil fuels cause acid rain, which is already adversely affecting rivers, lakes and forests. While some countries are reducing the levels of pollution, this must be done world wide. It is therefore essential to eliminate fossil-fuel power stations.

As for wind and solar power, they contributed only 0.15% of the world's energy production in 2000 and disfigure large areas of land. They are also relatively expensive and five times as dangerous as nuclear power as measured by deaths from all causes during production. There is no hope that they can supply our energy needs. The only practical substitute for fossil fuels is nuclear power. In 1988 some 1.9 x 10¹² kWh of electricity was generated by nuclear power stations. The same amount would be produced by burning 900 million tonnes of coal or 600 million tonnes of oil. In other words, the emission of 3000 million tonnes of carbon dioxide has been saved by using nuclear power, rather than coal. (While coal emits 850 tonnes of carbon dioxide per gigawatt hour, the figures for oil are 750, gas 500, nuclear 8, wind 7 and hydro 4.)

As countries switch to nuclear, their rate of carbon-dioxide emissions fall. Since 1970 France has halved its emissions, Japan (32% nuclear) has achieved a reduction of 20%, while the US (20% nuclear) has reduced it by only 6%. The emission of noxious gases like sulphur dioxide is also dramatically reduced by going nuclear.

The UK government, meanwhile, wants its emissions of greenhouse gases to be 10% lower by 2010 than they were in 1990. A reduction of 6% had been achieved by 1995, which was due to nuclear-power output rising by 39% between 1990 and 1994. However, if no more nuclear power stations are built, the level of emissions will rise steeply. In subsequent years, as older nuclear power stations are decommissioned, the UK will find it impossible to reach its target.

Although many new gas-fired power stations, which emit only half as much carbon dioxide as coal-fired power stations, are currently being built, the problem is that they leak methane, which has a "global-warming potential" of about 60 times that of carbon dioxide. These two effects approximately balance out, which means that we can expect no reduction in global warming by switching from coal to gas. Even if this methane effect is neglected, then if gas increases to 43.5% of total production, while coal declines to 2.5%, we can expect carbon-dioxide emissions to fall by 10%. And if nuclear rises to 43.5% at the expense of coal there will be a 20% fall.

If we do not solve the world's energy problems now, then they will soon be solved for us. We are living in a special period in human history when oil, gas and coal are readily available. At present rates of consumption, the oil and gas will be gone in less than 100 years, and coal in about 200-300 years. Fossil-fuel burning will then cease and alternatives will have to be found. If we continue to burn fossil fuels, we not only pollute the Earth and initiate global warming, we also deprive future generations of these valuable materials, the bases of petrochemical industries. Would it not be better to solve these problems now - using nuclear power - instead of waiting until it is too late?

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