The Microsoft Corp. co-founder said he wanted to view the early stages of the International Thermonuclear Experimental Reactor in Cadarache firsthand, to witness preparations "for the birth of a star on Earth."
Allen wasn't just a bystander in the hunt for the holy grail of nuclear power. He was among a growing number of ultra-rich clean-energy advocates pouring money into startups that are rushing to produce the first commercially viable fusion reactor long before the $23 billion ITER program's mid-century forecast.
Jeff Bezos, Bill Gates and Peter Thiel are just three of the billionaires chasing what the late physicist Stephen Hawking called humankind's most promising technology. Scientists have long known that fusion has the potential to revolutionize the energy industry, but development costs have been too high for all but a handful of governments and investors. Recent advances in exotic materials, 3D printing, machine learning and data processing are all changing that.