SUPERCONDUCTORS MAKE FUSION THE FUTURE FOR ENERGY Bruce Meechan reports on work relating to the international development of the ITER fusion reactor and hears from Antonio della Corte, a world authority on super-conductors.
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xtremes of temperature are quite literally at the core of the international effort to make fusion reactors a commercial reality in order to alleviate the world’s growing energy crisis and develop a sustainable energy source for the future with zero or low CO2 emission sources. While debate rages over the relative merits of wind turbines, shale gas and other ‘alternative’ technologies, work is underway to construct an experimental fusion reactor, known as the International Thermonuclear Experimental Reactor – or ITER – at Cadarache, Southern France. Crucial to its success will be the production of large electro-magnets in Italy, featuring the use of super-conducting cable supplied by Tratos Cavi SpA, the leading European manufacturer of Electrical, Electronic and Fibre Optic cables. Nuclear fusion – as opposed to fission where atoms split – has remained the elusive Holy Grail for physicists over the past half century, offering the promise of virtually 14 Industry Europe
unlimited power supply without the production of radioactive waste. What is more, they will use abundant sources of fuel, and will not leak radiation above normal background levels; so health risks diminish while the end-of-life disposal process for the reactor itself becomes far simpler. Therefore, although no one has an operational reactor, the day is coming and fusion reactors are now in experimental stages at several laboratories across the United States and around the world. It is anticipated that ITER will demonstrate the feasibility of using sustained fusion reactions to generate electricity. Employing nuclear fusion generates energy when two atoms join to form one; so in a fusion reactor, hydrogen atoms come together to form helium atoms, neutrons and vast amounts of energy or heat. In order to control and contain the collision process, very large and powerful magnets are required to propel the hydrogen particles. Critical is
the fact that unlike conventional magnets wound with copper, those featuring superconducting wire are far more compact and offer 99 per cent or higher efficiency.
Pushing the boundaries Creating the ITER reactor and the Japanese JT60SA unit are therefore massive undertakings, with international collaboration throughout. The Italian National Agency for New Technologies (ENEA) is responsible for putting together the tender for assembling very large quantities of super-conducting wire in conjunction with Tratos and Criotec; the latter being a specialist in ultra-low temperature work. Tratos became involved in the first stage of the contract, processing the specialised superconducting material, worth €90 million and supplied by Fusion for Energy (F4E), at its plant in Pieve Santo Stefano in Italy, after which it was transported to Criotec near Turin for final assembly.
