Science: Cadarache site of the ITER project

After 15 years of deliberation, the international scientific community has chosen Cadarache, in southern France, as the site for the international ITER project, with which scientists hope to tap the energy from thermonuclear fusion.

“ITER’s main objective of is to demonstrate the scientific feasibility of nuclear fusion”, announced Gabriel Marbach, deputy director of the Department of Controlled Fusion Research at the French Atomic Energy Commission (CEA) site in Cadarache. “However, this does not mean that industrial exploitation will be immediately possible following this experimental project”, he added. After many years of deliberation, France was selected to lead the international project. Among the potential locations considered for the project (Clarington in Ontario, Canada; Rokkasho-mura in the north of Honshu Island, Japan; Cadarache, France and Vandellos, Spain), the Cadarache site was selected as the most suitable. Located approximately 40 km to the north of Aix-en-Provence, Cadarache is one of the largest scientific and technological research hubs of France’s Provence-Alpes-Côte d’Azur southern region. The site employs over 4,100 people and is the biggest energy research and development centre in Europe. “One of the main reasons for selecting Cadarache is the site’s proximity to an existing research centre that can lend all of its expertise to the project, in addition to providing obvious logistical advantages”, stated Gabriel Marbach. Accordingly, the project’s first researchers, scheduled to arrive in October, will be immediately hosted at Cadarache. The other deciding factor in selecting the site is the effectiveness of France’s electricity network. A leader in research, development and innovation, the CEA is active in three main fields: energy, information and health technologies, and defence and national security. The CEA leverages its diverse programmes in order to meet two main objectives: to become the leading technological research organization in Europe and to ensure that the nuclear deterrent remains effective in the future. The CEA’s Cadarache centre has already been conducting nuclear fusion research for many years.

Nuclear energy can be produced in two ways: either by splitting heavy atomic nuclei (fission) or by fusing very light nuclei (nuclear fusion). While fission has long been harnessed to produce electricity, fusion has never produced usable power. Nuclear fusion occurs naturally in the core of stars - such as the sun - where the extreme conditions needed for fusion take place. The isotope hydrogen nuclei combine or fuse to form heavier nuclei and thus produce enormous amounts of energy that are the earth’s main source of heat and light. To achieve this type of reaction on earth, the two nuclei (positive charges that repel each other) must be brought close enough together. A certain amount of energy is thus essential to start the fusion reaction, which requires very high temperatures (between 100 and 200 million degrees) to make the nuclei move fast enough, as well as a certain level of confinement in order to increase the chances of the two atoms coming together. Researchers have been conducting fusion experiments for several years using devices called “tokamaks”. The ITER project will enable the international scientific community to build the world’s largest tokamak.

ITER began with an initiative at the 1985 Geneva Summit when the Soviet Union proposed building a next generation tokamak based on collaboration between the fusion programme’s four main partners. The following year, in October 1986, the United States, Europe and Japan responded favourably to this proposal. And so was born the ITER project, established under the auspices of the International Atomic Energy Agency (AIEA) and initially consisting of four participants: the United States, Japan, Russia and Europe (through which Canada was involved). The first study phase, Conceptual Design Activities (CDA), began a few years later in April 1988 and lasted two years. The first detailed engineering design phase, Engineering Design Activity (EDA), was completed at the end of 1998, at which date, for domestic reasons, the United States withdrew from the project. The three remaining partners focused their efforts on designing a facility with reduced costs and objectives. The EDA redesign phase for the new version was completed in July 2001. The following phase, Coordinated Technical Activities (CTA), terminated in 2002. Its objectives were to maintain the integrity of the project, to prepare the procedures for the joint construction and operation of ITER, and to provide technical support to the participant representatives, or teams, tasked with site-related negotiations. Quadripartite negotiations between Canada, Europe, Japan and the Russian Federation led to the selection of the ITER construction site, as well as to a consensus on the project’s financing and a broad outline of the future legal entity responsible for the construction and operation of ITER. The USA and China joined these negotiations in February 2003.

Construction on ITER is to begin in two years and to last ten years, before tests (scheduled to last 20 years) can begin. “Construction of an electricity-producing fusion power plant will not begin before 2050”, advised Gabriel Marbach. Fusion could then open the way to nearly unlimited and accessible energy resources with no impact on the greenhouse effect - while providing, perhaps, an initial response to future energy issues. Currently, 80% of non-renewable fossil fuels (coal, natural gas, oil) and 7% of nuclear energy provide the energy consumed globally. Based on current energy consumption, remaining reserves are estimated at 66 years for natural gas, 43 years for oil and 240 years for coal. Furthermore, based on recent estimates, the world’s population is expected to increase from 6.4 billion people to 9 billion by 2050. If the current consumption rate of fossil fuels is maintained, greenhouse gas concentrations are set to double.

Delphine Barrais

WEBSITES:

French Atomic Energy Commission: www.cea.fr Official ITER project website: www.iter.gouv.fr

Last updated: 22.11.2005