There are an international agreement to build a large, $4 Billion, reactor-scale device known as the ¨International Thermonuclear Experimental Reactor¨ ITER, based on nuclear fusion, and it is environmentally attractive, also sustainable energy source which is based on the same reaction that occur in our sun at very high temperatures.
The project ITER is in progress and there are other facilities such as JET(uk) or TFTR(us) where scientist are developing the necessary techniques to work in appropriate safely environment, and testing materials adequate to support high temperatures.
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