Repeatedly in recent years there have been calls for a revival of nuclear power. Yet that renaissance never seems to come.

Of the more than 200 countries in the world, only 30 use nuclear power. In July 2010, a total of 439 nuclear power plants with a net installed capacity of 373.038 gigawatts (GW) were connected to various national electricity grids, about 1.2GW more than at the beginning of 2006.

Roughly 16% of total energy needs (up to 25% in the highly industrialised countries) are now met by electric energy. Nuclear fission's contribution to total electric energy has decreased from about 18% more than 10 years ago to about 14% in 2008. On a worldwide scale, nuclear energy is thus only a small component of the global energy mix, and its share, contrary to widespread belief, is not on the rise.

During 2009, for example, nuclear power plants provided 2,560 terawatt hours (TWh)– equivalent to 2,560bn kilowatt hours of electric energy, about 1.6% lower than during 2008 and almost 4% lower than during the record year of 2006. Early results for the first four months of 2010 for the OECD countries indicate that so far the 2010 results are as low or lower than last year.

During the next five years, on average, roughly 10 new nuclear reactors are expected to become operational every year. But this assumes that all are constructed according to schedule, and the nuclear industry has rarely met its promised construction deadlines. According to the World Nuclear Association (WNA), 17 new reactors should have become operational between 2007 and 2009. But only five came onstream during this period – three in 2007 and two in 2009.

Moreover, four reactors were de-commissioned during 2009, and a larger number of reactors in Japan and Germany are not in use, owing to various technical stoppages. At least 100 older and smaller reactors will most likely be closed over the next 10-15 years.

Furthermore, during the past 10 years, only about two-thirds of worldwide demand for nuclear fuel was met from resources obtained from mining. The remaining 20,000 tonnes came from so-called secondary uranium sources – mainly inventories held by utilities and governments, reprocessed nuclear fuel, and stockpiles of depleted uranium. The supply from these sources will drop by roughly 10,000 tonnes at the end of 2013, when the Megatons to Megawatt programme between Russia and the United States – which recycles highly enriched uranium from Russian nuclear warheads into low-enriched uranium for nuclear power plants – comes to an end.

Current projections indicate that uranium shortages in the coming years can be avoided only if existing and new uranium mines operate according to plan. Indeed, extrapolations of global supply that foresee an increase in uranium mining are based on claims about the ability to expand output in Kazakhstan. So far, uranium mining in Kazakhstan has increased roughly as expected, from 4,357 tonnes in 2005 to 14,000 tonnes in 2009.

But it remains to be seen if the uranium mining in this country can indeed increase further. According to the WNA's latest estimates, from July 2010, the expected uranium extraction figure for 2010 has actually been decreased to 15,000 tonnes.

The view that the amount of energy derived from nuclear power worldwide will continue its slow decrease during the coming years is further supported by the 2008 annual report of the Euratom Supply Agency, which coordinates the long-term uranium needs of nuclear power plants within the European Union. According to the agency's forecast, uranium demand in Europe will fall from 21,747 tonnes in 2010 to roughly 16,000 tonnes by 2024.

These numbers indicate that the EU, currently producing about one-third of the world's nuclear electric energy, is heading for a reduction in nuclear-energy production of up to 20% over the coming 10 years. One can also expect that the current worldwide economic crisis will not help to accelerate the construction of nuclear power plants and new uranium mines.

In summary, the hard facts about nuclear energy are inconsistent with the possibility of a worldwide renaissance of nuclear energy. Indeed, they point toward a continuing slow phase-out of nuclear energy in most of the large OECD countries.

It seems unavoidable that energy consumers, especially in many rich countries, will have to learn to exchange their current worries about the distant future consequences of global warming for the reality of energy shortages during periods of peak demand. Such shortages could result either in chaotic supplies and power outages or in a coordinated policy of energy rationing.

In the absence of nuclear-energy revival, most of us will be forced to reduce our direct energy consumption. Let us hope that we can learn to adapt to simpler – though perhaps still satisfying – lifestyles.

• Michael Dittmar is a physicist at the Swiss Federal Institute of Technology Zürich (Eidgenössische Technische Hochschule), and works at Cern, the European Organisation for Nuclear Research in Geneva.

Copyright: Project Syndicate, 2010.

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