[u320]

> "Overnight, it basically changed the cost per watt of a fusion reactor by a factor of almost 40 in one day,"

So there is this myth that fusion enables unlimited cheap energy. This is 100% false. It's not unlimited at all. Most concepts relies on using lithium-6. That's not a super common element.

But more importantly, it's not cheap. That should be obvious, if you could reduce the cost per watt 40x and still not be competitive.

[ianburrell]

Lithium is a super common element. They are mining tens of thousands of tons per year increasing rapidly as make electric car batteries. Lithium-6 is 5% of lithium. Fusion reactors only need tons for breeding blanket.

[pfdietz]

The original ARC design had 950 tonnes of FLiBe, which contains 115 tonnes of Li-6. This is a substantial fraction of the Li-6 produced for the entire US hydrogen bomb program, all for a single 190 MW(e) (net) reactor.

[Tade0]

115 tonnes of Li-6 is what you get by sifting through the lithium required for ~200k electric cars.

Tesla alone could provide material for nine such reactors annually.

[pfdietz]

Sure, the input feed is not the problem. The problem is actually separating it. The technology used for the H-bombs is no longer acceptable due to mercury pollution. World Li isotope separation capacity currently is in kilograms per year (to produce pure Li-7 for pH control in fission reactors.)

And then there's the beryllium. A single one of those ARC reactors would use something like 40% of the current world annual beryllium production.