Will the ITER reactor ever have its day in the sun? Credit: ITER ORGANIZATION

It has been billed as the solution to tomorrow's energy crunch, but ITER, a massive fusion experiment by seven international partners, is under serious threat from a present-day problem: the financial crisis.

In a meeting on 26 May, the cash-strapped member states of the European Union (EU) were unable to agree on how to find the additional billions needed to finance construction of the giant reactor, which is sited near St-Paul-lès-Durance, France. The EU is set to contribute 45% of the construction costs for ITER, which some estimates now put at €15 billion (US$19 billion) — three times the 2006 cost estimate (see 'The ITER rollercoaster').

Left unresolved, the impasse in Europe will, at best, delay the project further. At worst, it could cause ITER to unravel entirely.

"I think the momentum of the project may be in very deep trouble," says one non-EU scientist involved with ITER who asked not to be named, citing the experiment's precarious position. "Time is pressing."

ITER has been a 25-year dream for fusion advocates: a step towards turning the promise of fusion — combining hydrogen isotopes into helium — into a practical power source. Fusion releases far more energy than the fission reactions of conventional nuclear power, but it is also more difficult to achieve. The doughnut-shaped ITER reactor would use superconducting magnets to heat and squeeze hydrogen until the device ignites a fusion reaction, releasing around ten times the power it consumes.boxed-text

Click for a larger version. Credit: SOURCE: ITER, VARIOUS

In 2006, when the EU, the United States, Russia, South Korea, China, India and Japan agreed to the project in its current form, ITER was estimated to cost around €5 billion to construct over a decade. But the rising cost of materials, gaps in the original design and the bureau­cracy needed to manage the project have caused the cost to balloon (see Nature 459, 488-489; 2009).

On 5 May the European Commission, which manages the project, released a memo that put the price of Europe's share of the construction at around €7.2 billion, nearly three times the 2006 estimate. The vagaries of how the seven partners budget for the project mean a full price-tag may never be known.

The most pressing problem is a €1.4-billion gap in Europe's budget for ITER in 2012–13. The commission's 5 May memo called on the 27 member states, which must ultimately pay for ITER, to "provide the additional resources necessary" for the project.

The request could not have come at a worse time for Europe. Faced with an economic crisis in Greece that could spread, the EU has just approved a costly €500-billion bailout package for eurozone countries. Meanwhile, many nations are desperately trying to trim their domestic budgets in an effort to right the continent's troubled finances.

The crunch is so serious that some European states have gone as far as to ask the commission to investigate the possibility of withdrawing from ITER, according to sources familiar with the negotiations. The price of such a withdrawal would probably be in the billions, as the treaty governing ITER requires heavy compensation to other partners.

Mark English, a spokesman for the European Commission, declined to comment on whether member states had asked for an analysis of withdrawal. In a press conference during the most recent meeting, European officials said they remained committed to ITER. "I think that, with vision, we can overcome the difficulties," Máire Geoghegan-Quinn, the European commissioner for research, told reporters on 26 May.

One temporary solution would be a loan from the European Investment Bank to cover the immediate €1.4-billion budget gap. That would work in the short term, but member states would still have to come up with a plan to cover the full €7.2-billion costs. Another possibility, floated by Annette Schavan, Germany's research minister, would be to redesign the machine, possibly building a smaller version.

But scaling back ITER at this stage is unrealistic, says Stephen Dean, president of Fusion Power Associates, a non-profit advocacy group based in Gaithersburg, Maryland. The planned reactor is already half the size that scientists originally hoped it would be, and any further shrinking would risk making the machine too small to achieve its goals.

Europe's member states have formed a task force to discuss how to pay for the project. The group will meet weekly in the run-up to a meeting of the full ITER council on 17 June. If the EU cannot reach an agreement in time, ITER's six other members may decide to delay the council meeting until Europe has found a way forward, insiders say.

Dean says he thinks that ITER's other partners may ultimately have to provide more aid if the project is to stay on track. "If they want the [current] schedule that badly, they're going to have to come up with more money," he adds.

More fundamentally, Dean says, the seemingly endless succession of cost increases and delays may cause a rethink of fusion entirely. "We're supposedly developing a power source that's going to compete with coal and nuclear," he says. But the experience so far does not bode well: "There are serious questions about the affordability of fusion as a whole as a result of ITER."

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