The generation of excess energy by controlled fusion is still an open problem.
Some say a crash program for controlled fusion, the principle of the hydrogen bomb, is best.
And if we do ever achieve controlled fusion, that energy will be used in precisely the same manner!
A fusor can also produce controlled fusion and is a useful neutron source.
In 1951 the first major efforts to produce controlled fusion for power production started in earnest.
But it was not until a hundred and fifty years ago that we achieved the first controlled fusion.
Today the United States still has its own effort at controlled fusion.
By the time I stopped, we had lost controlled fusion entirely.
The tokamak has since gone on to become the most studied approach to controlled fusion.