Nuclear fusion is what makes our sun work. Every second, this process transforms astronomic quantities (600 million tonnes per second) of hydrogen atoms into helium, with the liberation of a phenomenal amount of energy. The object of nuclear fusion is to reproduce this process on Earth on our tiny human scale.
The main difficulty associated with nuclear fusion is that before recovering the energy, the hydrogen must be heated to 200 million degrees. That is exceedingly hot! So hot in fact that no known material resists such temperatures. So, what can be done? We put the fusion gas into a non-material container, a magnetic field of enormous intensity.
The fusion machines are called tokamak reactors.
For the moment, we have succeeded in producing fusion energy only during a very brief time (the current record is one second), and we use more energy to heat and to contain the fusion gas than is recovered from the fusion process. Therefore, a lot remains to be done. The first power plants producing electricity by fusion are not expected to be operational before 2050. Getting there is going to require a lot of time and a lot of money, but the effort will be well worth it: a virtually inexhaustible source of energy, generating very limited radioactive waste and no greenhouse gases. Is it the energy of the future? Rendezvous in several decades!
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