Teller: X shut down its nuclear fusion project after 1,000 plasma shots
Astro Teller · Tries 1,000 ideas & kills most—how X built Waymo & Google Brain | X (Alphabet) · PMF Show · Jul 13, 2026 · at 30:25
Astro Teller, Captain of Moonshots at Alphabet's X, shares how the Moonshot Factory rigorously validated and ultimately terminated an internal nuclear fusion effort.
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“We closed this down about a year and a half ago. We had a fusion project. We ran it. We did build something the size of a house. We did almost a thousand plasma shots. We convinced ourself it was not going to change the world. And we closed the project down”
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