Reply #28: the next milestone to fusion power will be ITER. [View All]

[megatherium]

ITER, when it is built in about a decade, is expected to demonstrate "ignition", when a plasma undergoes a self-sustaining fusion reaction. (Currently, ITER is mired in a political dispute about which country will host it, Japan or France. The US dropped out of the ITER project, but is now back in.) ITER is supposed to have a reaction go for hundreds of seconds at a time, but it will be clear from that that reactions of indefinite duration will be feasible. ITER will produce much more energy than input to start the reaction. It won't produce usuable electricity; that will be the successor project (which if memory serves, will be called DEMO). That will be three to four decades from now.

One important point: the plasma physicists are now getting confident that ITER and its successor will perform as hoped. Economic fusion power will be possible by mid century. (The plasma physicists are getting more confident because they are getting much better at building good computer models for the behavior of plasma, a primary objective of the current existing generation of fusion experiments.)

But another important point: solar PV is improving in efficiency and price by 4% a year. It may well be very competitive on its own merits by the time fusion is available. Either way, our future involves fusion energy: that is how the Sun gets its power.