People’s Perception of Experimental Installations for Sustainable Energy: The Case of IFMIF-DONES

Nuclear facilities are a main milestone in the long way to sustainable energy. Beyond the well-known fission centrals, the necessity of cleaner, more efficient and almost unlimited energy reducing waste to almost zero is a major challenge in the next decades. This is the case with nuclear fusion. Different experimental installations to definitively control this nuclear power are proliferating in different countries. However, citizens in the surroundings of cities and villages where these installations are going to be settled are frequently reluctant because of doubts about the expected benefits and the potential hazards. In this framework, knowing the opinion of people and their perception of experimental fusion facilities is essential for researchers, administrations and rulemaking bodies planning future fusion plants. This is the case for IFMIF-DONES, a neutron irradiation facility to determine the most suitable materials for the future fusion reactors. The construction of this installation is starting in Escúzar (Granada, Spain), and this work presents a large survey among 311 people living or working in the village. Their perception, fears, hopes and other variables are analyzed, and the conclusions for future installations and their impact on the energy policy are presented.

In Vitro Analysis of the Effects of ITER-Like Tungsten Nanoparticles: Cytotoxicity and Epigenotoxicity in BEAS-2B Cells

Tungsten was chosen as a wall component to interact with the plasma generated by the International Thermonuclear Experimental fusion Reactor (ITER). Nevertheless, during plasma operation tritiated tungsten nanoparticles (W-NPs) will be formed and potentially released into the environment following a Loss-Of-Vacuum-Accident, causing occupational or accidental exposure. We therefore investigated, in the bronchial human-derived BEAS-2B cell line, the cytotoxic and epigenotoxic effects of two types of ITER-like W-NPs (plasma sputtering or laser ablation), in their pristine, hydrogenated, and tritiated forms. Long exposures (24 h) induced significant cytotoxicity, especially for the hydrogenated ones. Plasma W-NPs impaired cytostasis more severely than the laser ones and both types and forms of W-NPs induced significant micronuclei formation, as shown by cytokinesis-block micronucleus assay. Single DNA strand breaks, potentially triggered by oxidative stress, occurred upon exposure to W-NPs and independently of their form, as observed by alkaline comet assay. After 24 h it was shown that more than 50% of W was dissolved via oxidative dissolution. Overall, our results indicate that W-NPs can affect the in vitro viability of BEAS-2B cells and induce epigenotoxic alterations. We could not observe significant differences between plasma and laser W-NPs so their toxicity might not be triggered by the synthesis method.

Mechanical Characterization of Dissimilar Alloys Joined using Electron Beam Welding: Technical Note

Electron Beam Welding (EBW) is used in various industrial applications for joining dissimilar metals due to its accuracy and good quality joints. International Thermonuclear Experimental Reactor (ITER) is the first experimental fusion power generating reactor in India. It uses a host of metals and alloys like Ti-6Al-4V, Ni-Al bronze and a special copper alloy (CRZ). This investigation aims to study the metallurgical and mechanical aspects of CRZ alloy and its EBW joint with a dissimilar metal like Nickel and stainless steel. Characterization includes material composition and effect of heat-treatment. The CRZ alloys were solution annealed at the temperature of 980 degrees C for 15 minutes and then aged at 460-480 degrees C for 4.5 hrs. The EBW welded joints were fabricated with CRZ-CRZ, CRZ-Ni and Ni-SS combination. The microstructure and mechanical properties were analyzed.