ITER project, Cadarache, France
The ITER (International Thermonuclear Experimental Reactor) project is a unique example of international cooperation in the search for an inexhaustible source of safe and environmentally-friendly energy. Europe, China, South Korea, India, Japan, Russia and the United States are working together to research the possibility of harnessing the energy from fusion, reproducing the reaction that lights up the stars.
This would involve demonstrating that the fusion of two types of hydrogen (deuterium and tritium) in a tokamak reactor could become a viable energy source and generate electricity. From this starting point, the reactor aims to produce 10 times more energy than it takes to trigger nuclear fusion. So for 50MW of electricity consumed, ITER will generate 500MW of thermal energy.
A world-class project in Cadarache (south of France)
A consortium led by VINCI (58.3%), with VINCI Construction Grands Projets, Dodin Campenon Bernard and VINCI Construction France has concluded an agreement with Fusion for Energy (F4E), the European Union organisation responsible for ensuring Europe's contribution to the ITER project, for the construction of the tokamak reactor building and the design-construction of nine support buildings on the Cadarache site, north of Aix-en-Provence.
The main building will house the reactor, a cylinder, 28m in diameter, 29m high and weighing 23,000 tonnes. With its two support buildings, the tokamak will be housed in a reinforced concrete structure 120m long, 80m wide and 80m high. Other support buildings include the assembly building, a two-storey building and various industrial buildings. The reactor is equipped with large nuclear doors (4m x 4m, 40 tonnes), resistant to radiation and excessive pressure. The VINCI Group companies were responsible for raising the steel frame, weighing 800 tonnes, on the roof of the assembly building.
Protecting ITER from seismic events – a challenge taken on by VINCI Construction Grands Projets
In order to have the necessary infrastructure from the start of the installation project, VINCI Construction Grands Projets dug a seismic isolation pit 126m long, 86m wide and 15m deep. The purpose of this pit was to allow the construction of a first slab, as well as retaining walls. On top of this slab, 493 concrete pillars were positioned, each topped off by a seismic pad and capable of absorbing lateral movements of 10cm, making it possible to contain ground movements in the event of seismic activity. A second slab above these pads forms the floor of the ITER tokamak complex.
7 November 2019: ITER reaches a milestone
The completion, on deadline, of the important civil engineering works stage was symbolically marked by the concreting, on 7 November 2019, of the last pad of the upper level of the tokamak building. The teams still on site will be able to move to the next stage – installation of the metal roof structure – thereby staying on schedule to produce the first plasma, the energy generating element, in 2025.
ITER is a one-of-a-kind research programme in terms of its complexity, precision and size.
“ITER is a one-of-a-kind research programme in terms of its complexity, precision and size. With ITER, we are humbly helping to implement one of the greatest and most ambitious energy projects of our time, designed to make electricity available throughout the world without CO2 emissions or radiological risk. For us, as a builder, it is a matter of great pride to have laid the cornerstone of a structure of such importance to humanity,” said Jérôme Stubler, Chairman of VINCI Construction.