Progress of ITER and its importance for fusion development

Abstract This paper summarizes the progress of the ITER Project and highlights its significance for fusion development, especially in light of recent global growth in public and private fusion initiatives. Following a significant series of Project reforms that included reorganization, adjustments to major contracts, renewal of trust with the regulator, and repair of key components, the ITER Project has performed with unprecedented schedule and cost efficiency over the past two years, progressing strongly under its new Baseline 2024. This baseline is a comprehensive and feasible plan for assembly, integrated commissioning and operation under a stepwise safety demonstration, developed to deliver the key objectives of ITER, indispensable for fusion and achievable only by ITER, as early as possible. Significant progress on the first-of-a-kind manufacture of fusion components and formation of their associated global supply chains has been led by the ITER Organization, the Domestic Agencies of the seven Members, and their national industries. These achievements have included repairs of some Vacuum Vessel (VV) bevel joints and thermal shield cooling pipes, completion of all superconducting magnets, completion of six of the nine VV sectors, start of series production of divertor components and gyrotrons for the Electron Cyclotron heating system, and more. Assembly and installation of VV sector modules are progressing with a Schedule Performance Index above 1, with three sectors installed in final position by November 2025. Commissioning of plant systems, including the cooling water system, the pulsed power electrical switchyard, and the world’s largest cryoplant, is also going well. A new Magnet Cold Test Facility is nearing completion and will start operation in winter 2025. In the Neutral Beam Test Facility, the SPIDER experiment achieved record current density, and MITICA final installation is progressing as planned. In the Baseline 2024, the first operational phase is a scientifically meaningful research phase including deuterium–deuterium H-mode operation and achievement of full magnetic energy in L-mode operation. Towards these operations, extensive integrated and advanced plasma modelling and predictions have been carried out. Using these studies and collaborating with other tokamak research facilities globally, the tungsten first wall concept has been assessed and adopted. Reflecting on recent developments in fusion, this paper also considers ITER’s mission and objectives in the framework of the remaining challenges still to be addressed for fusion to become a practical source of electric power generation.