The new director of the ITER experimental fusion reactor project is weighing cost-cutting steps that are certain to be controversial among fusion researchers.
The ITER reactor, which is now beginning construction at Cadarache in southern France, has drawn a lot of flak in recent years because of its ballooning price tag, which has more than doubled to about €16 billion. The seven members of the project—China, the European Union, India, Japan, South Korea, Russia, and the United States—gave their final approval of the project's design, cost, and schedule in July. But cost containment remains a priority for Director-General Osamu Motojima, who set up a panel to find 10% in savings shortly after taking over in July.
Last week, at a meeting in Cadarache of ITER's Science and Technology Advisory Committee, delegates discussed 22 ways to reduce costs. One possibility is eliminating magnetic coils for controlling disturbances in the superheated hydrogen gas, or plasma, at the heart of the reactor. The disturbances in question, called edge localized modes (ELMs), are like mini-earthquakes in the plasma and can cause it to bulge out and touch the side of the containment vessel, killing fusion and potentially causing damage.
Researchers have developed several ways to quell ELMs. One recent innovation is to calm them with low-level magnetic fields, using magnetic coils built inside the reactor vessel. That idea came too late to be included in the original ITER design, however, and implementing it would not come cheaply.
Another possible cost saving measure is to dispense with testing of the reactor's giant containment magnets. Some of these enormous superconducting coils, each weighing hundreds of tonnes, are so large that they have to be wound on site in a special 250-meter-long facility. Some ITER members have insisted that the magnets must be tested at their normal operating temperatures before installation because a major fault could kill the whole project. But cooling these massive devices to cryogenic temperatures would require building another purpose-built facility.
The ITER organization and the various committees will present their recommendations to the next ITER Council meeting on 17 November in Cadarache.