As the cost of ITER is now estimated at 16G€, I want to point out that such a tokamak is completely useless, because it requires unavailable tritium. That is: - Tritium does not exist naturally, because its life is about 20 years and it isn't produced on Earth by any process; "in the ocean" is just false, by ignorance or by deception. - Tritium is produced by uranium reactors, in tiny amounts. A fission reaction produces 200MeV heat to create less than one available neutron, which is necessary to produce one tritium atom, for instance from lithium. Then, one tritium consumed in a tokamak produces less than 20MeV heat. In other words, one 1GW tokamak needs >10GW fission reactors operating. - Just as any magnetic confinement reactors, Tokamaks don't produce tritium. One reason: the D-T reaction produces only one neutron, and one neutron would produce less than one tritium, for instance from a lithium cover. Some would like to pretend that "neutron multiplicators" like lead achieve a tritium regeneration factor of 1.1 but this is a theoretical best case supposing there are no other design constraints on a tokamak... And well, there are design constraints, which in fact prevent doing anything more than keeping the plasma hot and confined... - Tokamaks can't consume anything else than tritium in any foreseeable future. Other reactions than D-T, like D-D or D-Li, require conditions even much more difficult to achieve in the plasma. Nobody would predict a number of half-centuries more before these reactions are usable. So: - Tokamaks can't replace fission reactors, not even a small fraction of them. - Tokamaks are useless. ITER is useless. - We can save 16G€ worth of physicist time to develop useful and sensible projects, like geothermal energy, or like storage of wind electricity or Solar heat. We would have solved all of them with the money already wasted in tokamaks.