The human race has been researching fusion energy for more than 100 years, to try to achieve a non-polluting energy source. The theory has been known for a long time, but in practice is where the problems arise.
A nucleus of atoms must be heated to more than 100 million degrees (a temperature similar to that of the Sun) for the atoms to clump together and release enormous amounts of energy. And also you have to control that energy so that it does not destroy the container.
Explained with simple words it is quite simple, but actually doing it is very complex. Although it is true that important advances have been made in recent years and there are many people (public and private companies) investing a lot of money in trying to achieve it.
And the most optimistic estimate that this energy can be more or less controlled in 20 or 30 years. But that remains to be seen, since they have been announcing the same thing, or similar things, for more than 50 years.
What I am commenting on today is what has recently happened in an American research laboratory (Lawrence Livermore's, in California). In their latest experiment they managed to generate more energy than they introduced with the lasers to place the atoms at about 100 million degrees. And that energy that they obtained was so great that it broke the machine that they had destined to analyze the results.
But most important of all, is that they managed to obtain 30% more energy than they used in lasers to excite the atoms. And that is an important milestone.
What happens is that there is a long way to go. These tests are carried out with very low energy levels, and moving to the energies required for the electricity generation industry will be very complex and will take many years.
But since the benefits can be enormous, there are many people researching and investing in the subject. Bill Gates, Jeff Bezos, etc… they put part of their money in companies working in this field. Just by way of example, private companies have invested almost 3 trillion dollars in the last year.
It seems clear that nuclear fusion power is starting to get closer, but don't think you'll see it in a few years.
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