Nuclear power promises clean energy for developing countries. Dave Elliott charts its progress and prospects after the accident at Fukushima.
For 60 years, using uranium to generate electricity in nuclear power plants has been promoted as a way to provide cheap, clean energy for a prosperous new world.
Nuclear energy now supplies around 13.8 per cent of the world's electricity, with most plants operating in the developed world.  And since nuclear plants do not emit any carbon dioxide, they are seen as one way to respond to climate change.
However, opponents of the technology point to drawbacks: the high cost of building, operating and maintaining nuclear power plants; handling their radioactive wastes; and difficulties in effectively regulating environmental and human safety risks.
Mining and processing reactor fuel is also energy intensive, so the overall nuclear system is not actually carbon free.
All this creates a dilemma for developing countries, which need a relatively cheap source of energy. Some developing countries have found nuclear energy an attractive option, and have invested in nuclear plants (see Table 1).
But after the nuclear accident at the Fukushima power plant that followed the March 2011 tsunami in Japan, some others who were thinking of doing so have now abandoned their plans (see Table 2)
Developing countries seeking nuclear
No longer interested
The Fukushima accident undermined confidence in, and support for, nuclear power around the world. Opinions vary from country to country, but over 60 per cent of people are now opposing nuclear power. (See Box 1.)
BOX 1: Public opinion after Fukushima
A 24-country public opinion study carried out in May 2011  found that 62 per cent of those asked opposed nuclear power 25 per cent had changed their mind, tipping the scales against the nuclear option. Opposition in some developing countries and in much of Europe was very high.
For example, 81 per cent of those asked in Mexico whether they support nuclear power as a way of generating electricity were against it, 52 per cent of them strongly. In Argentina, opposition was at 72 per cent, and in Brazil 69 per cent. Opposition was also strong in Indonesia (67 per cent), South Korea (61 per cent), South Africa (60 per cent), China (58 per cent) and Saudi Arabia (58 per cent). Within the developing world, only in India was there a majority in support (61 per cent).
Poll results do, of course, depend on the questions used. When asked if they saw nuclear power as a viable long-term option, 50 per cent of respondents in India said no; 50 per cent also didn't see it as a way to modernise electricity production. The respondents in the other developing countries all offered lower scores to these two questions, with the exception of Saudi Arabia. There, 54 per cent saw nuclear power as a viable long-term option, indicating more optimism in this region.
Clearly, some developing countries in need of a continuous, relatively low-carbon supply of electricity still see nuclear energy as a way forward in spite of its risks, and a turbulent past.
The nuclear story
Civil nuclear power emerged from programmes to develop nuclear weapons in the USA and USSR during World War II. This led in the 1960s to major reactor developments.
In the 1970s, the technology spread to countries such as China, India and Japan which developed civil nuclear programmes supported either by the United States or the Soviet Union. Some other developing countries also took up the nuclear option, notably Argentina, Brazil, Mexico, South Africa and South Korea.
However, in 1979 there was a major nuclear accident at the Three Mile Island plant in the United States. This, along with the poor economics of nuclear compared with other energy options such as coal, halted new nuclear developments in the United States. Although the net fuel costs of nuclear plants have been lower than fossil-fuel plants, the capital cost typically runs at around three times higher, and tends to rise as safety requirements grow 
Then came the even larger nuclear disaster at Chernobyl in the Ukraine in 1986, to which several thousand deaths have been attributed, although the death toll is still being debated. At that point, many (but not all) European countries backed off from nuclear energy.
In the late 1990s, with climate change a growing issue, the nuclear industry tried to revive its market position. And in the early 2000s, under then US President George W. Bush, the US-led Global Nuclear Energy Partnership programme aimed to promote nuclear power in developing countries.
President Obama has abandoned this programme, but by the late 2000s something of a global nuclear renaissance had already emerged, led by China and India. And in the early 2010s, some EU countries were reversing their opposition to nuclear. Russia was expanding its programme and the United States was looking to start a new programme.
Keen to expand the market further, some nuclear technology vendors also looked elsewhere to South America, for example, where Chile and Venezuela had expressed interest (Russia offering to help Venezuela), and also to the Middle East.
Egypt has been another major player in promoting the nuclear option, along with Saudi Arabia, and the UAE. Qatar, Kuwait and Jordan have also expressed interest in nuclear energy. Iran already has a nuclear programme, as does Israel, although, so far, both are small.
Dual use of nuclear technology
Most of the world's nuclear plants are based on the US Pressurised Water Reactor design (PWRs) (See Figure 1). Variants such as the Boiling Water Reactor (BWRs), and others notably various Russian designs are less common.
Some newer upgraded versions of the PWR are now emerging, such as the French European Pressurized Reactor (EPR) and the US AP1000.
Most modern nuclear plants have a power-generating capacity of 10001,600 megawatts. Smaller, mini-reactor designs are producing power in the 20-300MW range. 
Whatever the specific design, the basics of their operation are the same. A rare component of uranium ore, the isotope Uranium-235 (U235), is the only naturally occurring isotope that, if concentrated, can sustain a chain reaction of nuclear fission that produces large amounts of heat and radiation. The heat can be used to raise steam to drive turbines as in a conventional power station, producing electricity.
Plutonium, another radioactive element, is produced as an inevitable by-product of nuclear fission. It is also the main material used in nuclear weapons. But U235, suitably concentrated, can also be used for weapons. So to make a nuclear bomb you either need an 'enrichment' system to concentrate U235, or a reactor to make plutonium.
Because most reactors need slightly enriched uranium to run, knowing whether a specific enrichment activity is being used to produce fuel for civil nuclear power or for nuclear weapons takes close monitoring. Similarly, it can be difficult to know when, and if, reactors are being used to make military grade plutonium.
Certainly, most known nuclear weapons have been developed in countries that already have civil nuclear power programmes. Given the overlap in the technologies, most countries signed the Non Proliferation Treaty (NPT) in 1970, which seeks to control the military use of the technology.
India, however, did not sign, and has produced a nuclear weapon of its own. So has Pakistan and, it is believed, Israel too. North Korea initially signed, but there has since been a long-running battle over compliance with the treaty, as there also is with Iran.
Costs and hazards
The overlapping civilian and military uses of nuclear technology can lead to political conflict a major drawback. But there are others too.
Nuclear plants are very capital intensive, in part due to their complexity and high safety requirements. Although fuel costs are lower than for fossil fuel plants, the cost of the electricity they produce can be higher, depending on a range of factors including the cost of borrowing to pay for construction and whether government subsidies are available.
Table 3 shows estimates for the cost of electricity produced by nuclear and coal-fired power plants, assuming public sector funding (5 per cent discount rate) and private sector funding (10 per cent discount rate). They show wide variation, and experts disagree on how to represent fully the wider social and environmental costs of different energy sources.
And problems with new projects make estimated costs unrealistic. For example, a 1600 megawatt EPR being built in France was originally expected to cost 3.3 billion, but after long construction delays looks likely to cost 6 billion .
Dealing with the radioactive wastes produced, and with decommissioning the plant when it has reached the end of its useful life, is also expensive. There are plans for putting the very long lived radioactive wastes in deep geological repositories, but so far none actually exist. The wastes will remain dangerous long after the power plants, which have operational lifetimes of around 40 years, have closed. For example, it will take around 24,000 years for the activity of plutonium to be halved.
The risk of major accidents is another major concern their social and economic costs can be substantial and long-lasting. For example, Belarus has estimated its economic losses due to the cumulative health and social impacts of the Chernobyl disaster over 30 years at US $235 billion. And 57 per cent of government spending in Ukraine still goes to Chernobyl-related benefit programmes .
More recently, the Japan Center for Economic Research has estimated that the costs of the nuclear accident at Fukushima could reach $250 billion, including compensation for the 180,000 people evacuated from the area. 
As the Fukushima accident indicated, nuclear power raises major safety challenges not least in dealing with emergencies and developing the technical capabilities to run the plants and their associated infrastructure, including waste management, safely.
There is also the issue of fuel availability. The main reserves of uranium are in Australia, Canada, Namibia and Kazakhstan, and are said to be enough for around 70 years at current use rates. 
New finds of uranium fuel and new uranium-using technology may help extend that. For example, fast neutron 'breeder' reactors could help stretch uranium reserves by 'breeding' plutonium from otherwise wasted uranium. Some prototypes have been built, but so far this is a relatively undeveloped technology, with potential safety and security problems. 
Given possible shortages of uranium, some countries are exploring using thorium, which is three times more abundant than uranium. Some prototypes already exist, and both India and China are looking at this option.
But in the longer term, the prospects for nuclear fission are inevitably limited by the availability of a finite fuel. So nuclear fission cannot expand enough to permanently replace fossil fuels. This suggests that nuclear power may not be the most suitable option fordealing with climate change.
One possible option for that is nuclear fusion, since the fuel needed is much less constrained. Some of it (deuterium) can be obtained from sea water, and tritium can be produced from lithium.
But this is not an immediate prospect fusion is an as yet undeveloped technology. It requires either very high temperatures (around 200 million degrees Celcius) or high powered focused-laser pulses to force nuclei to fuse and release energy. So far, it has not proved possible to produce more energy than that needed to run the reaction, or to keep the fusion reaction stable for longer than a few seconds.
Enthusiasts for fusion say that, if all goes well with the multi-billion dollar international research programmes, fusion could supply around 20 per cent of global electricity by 2100.  But there is no guarantee of this.
Much more developed are some of the renewable energy options, using natural and inexhaustible energy flows like the winds, tides and the sun. Renewable sources already provide 20 per cent of global electricity (if hydro power is included), and the prospects for rapid expansion are good the Intergovernmental Panel on Climate Change has suggested that renewables might supply 77 per cent of global electricity by 2050. 
Who's in and who's out
The Fukushima nuclear disaster left nuclear power at something of a crossroad, as it was after the Chernobyl accident.
Several developed countries have turned away from the nuclear option. Japan has decided to abandon its expansion plans and is considering a complete phase-out of nuclear, while Germany has launched a phase-out programme both countries are backing renewables instead.
Italy has also given up its nuclear plans, as has Switzerland. Even traditionally pro-nuclear France has said it will consider a full nuclear phase out by 2050.
The pattern in the developing world is more mixed. China is reassessing its nuclear programme, and considering cutting back on the official target of installing 80 GW by 2020.At present China gets less than 2 per cent of its electricity from nuclear energy, but had been planning to expand that to around 4 per cent by 2020. Although a small percentage, this represents a very large programme, given the size of the country.
But to put that in perspective, China is aiming to get 15 per cent of its total energy (not just electricity) from renewable and other low-carbon energy options by 2020.
India is something of a special case. As a non-signatory to the NPT, it has sometimes found it difficult to access uranium from abroad because of international restrictions on its access to nuclear fuel. Nevertheless, and despite strong local opposition, they are pushing ahead with an ambitious expansion programme to 20GW by 2020.
Elsewhere, in South-East Asia, Taiwan and South Korea are reassessing their nuclear programmes, and Thailand and Malaysia have abandoned their nuclear plans. The Philippines government says it may 'rechannel' its 100m nuclear budget to renewables. But Vietnam has decided to push ahead with its plan for 14 nuclear plants by 2030.
In the Middle East, Saudi Arabia is considering a US$100 billion programme to build 16 new plants by 2030. Abu Dhabi's first plant is due to open in 2017, with three more to follow. And Turkey is also pressing ahead with its nuclear programme. However Kuwait has now said it no longer wants to go down the nuclear path, and Qatar has made a similar announcement.
In Africa, South Africa already gets 6 per cent of its electricity from nuclear power, and had been planning to expand on that capacity. But the financial crisis has led it to abandon these plans, at least temporarily, as well as its advanced 'pebble-bed' mini-reactor project.
And although South Africa appears keen to continue with its nuclear programme, it also sees renewables as making an even larger contribution to meeting the country's future energy needs.
Kenya, by contrast, seems keen to focus very heavily on nuclear power. It has plans for a multi-billion programme, which, if it went ahead, would supply most of the country's power within the next 15 years.
The nuclear story is far from over, in developed and developing countries alike.
In the longer term, new nuclear technologies may emerge that are safer and more cost-effective, perhaps producing less waste and using fuel more efficiently.
As things stand, the alternative is the rapid deployment of renewable energy technologies, some of which are widely used. Developing countries need to weigh up the evidence available now as they consider the option of nuclear for their energy future.
Dave Elliott is emeritus professor of technology policy at Open University, United Kingdom.
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