The foundations of the building that will house the world’s largest experimental tokamak fusion reactor ITER have been completed with work entering the second phase of construction.
Workers at the Cadarache nuclear research facility in the south of France have started building walls around the large excavated area where a seven-storey building housing the ambitious project and related facilities will stand – another major milestone after the completion of the Tokamak Complex basement in August.
"The start of pouring activities for the massive Tokamak Complex is an important and exciting moment for the ITER Project," said ITER director-general Osamu Motojima. "Years of hard work by all ITER members are bearing fruit as the ITER facility takes shape in France and as the manufacturing of the systems and components advances. ITER is progressing on all fronts."
The first phase of construction, involving the creation of the ground support structure for the Tokamak Complex, took four years to finish. Between August 2010 and 2014, workers dug the 17m-deep Tokamak Complex Seismic Pit, created a ground-level basement and retaining walls, installed 493 seismic columns and pads and created the B2 foundation slab that will support some 400,000 tonnes of building equipment including the 23,000-ton tokamak.
"Europe is taking ITER construction to the next level,” said Henrik Bindslev, director of Fusion for Energy – the agency overseeing the project.
“The basemat is where scientific work and industrial know-how will come together and be deployed to seize the power of fusion energy."
The seven-storey Tokamak Complex will house not only the ITER Tokamak itslef, but also more than 30 different plant systems including cooling systems and electrical power supplies. Eighty metres tall, 120m long and 80m wide, the construction of the Tokamak Complex will require 16,000 tonnes of rebar, 150,000 cubic metres of concrete and 7,500 tonnes of steel.
French-Spanish consortium VFR is responsible for the construction as part of a €300m contract, signed in December 2012.
As part of the deal, VFR will also build the ITER Assembly Building and facilities to house heating, ventilation and air-conditioning systems, as well as cryoplant compressor and a coldbox.
Three-hundred workers are currently employed on the construction site but the number is expected to increase to 2,000 in the upcoming years.
ITER is scheduled for completion in 2019 with first attempts to produce plasma in a nuclear fusion reaction to take place in 2020. However, regular operations are not expected to commence before 2027, 11 years behind the original schedule.
The programme was initiated in 1985 and formally approved in 2006 with an estimated budget of €10bn.