BioEd Online

What is ITER?

ITER is a giant, €5 billion (US$6 billion) machine designed to prove that fusion power can work. It will use magnetic fields to confine hydrogen isotopes and heat them to hundreds of millions of degrees Celcius. If all goes well, the isotopes will fuse together producing some 500 megawatts of power in the process.

What happened today?

The European Union (EU), United States, Japan, South Korea, Russia, China and India all signed an agreement to build ITER. The EU will commit around half the costs of the machine, with each of the other donors contributing just under 10%.

Didn't these nations already agree to build ITER last year?

In June of 2005, the parties agreed to build ITER in the south of France at Cadarache. That decision came after nearly a year of bickering between the EU and Japan about who would get to host the machine.

Although most of the details were laid out in 2005, the nations still had to finalize them and present the plans to their home governments.

What's the next step?

Some parties, such as South Korea, will still have to take the proposal back to their parliaments for final ratifications. Meanwhile ITER's technical team will begin finalizing the design. In the spring of 2007, workers will begin clearing and levelling land in Cadarache, in preparation for building.

In the meantime, individual countries will begin working on their contributions to the project. Most of ITER will be paid for 'in kind', meaning that individual nations will supply parts, rather than cash, for the machine. Coordinating these contributions is expected to be one of the most ambitious, and difficult, parts of the project.

When will we know whether ITER has been a success?

Not until at least 2016, when the first plasma will be created inside the machine. In truth, it could take several more years before scientists and engineers on the project can coax a power-producing plasma from ITER. The project is expected to run for a decade, and researchers will use that time to gather data to develop a second, possible demonstration reactor that would produce electricity.

What would happen if we put that much money into renewable energy instead?

An investment of that size could make a huge difference to the capacity of electricity plants based on things such as wind, solar and geothermal energy and it would have that impact in the very near future. It is impossible to know how successful or cheap fusion power, in comparison, might one day be. But a range of future energy options is inarguably a good thing. For now, some of the scientists involved with ITER are as interested in the basic science as they are in eventual applications.

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