Most fusion startups are chasing the same fuel. This one picked the hardest one on purpose. ⚛️
Borealis Fusion (New York, founded 2026, $6M seed) is betting on proton-boron fusion instead of the usual deuterium-tritium.
Why it's tempting: → A proton hits boron-11 and you get three helium nuclei and 8.7 MeV → Almost no stray neutrons, so far less damage to the machine → The fuel is cheap and abundant
The catch: it needs around 1.5 billion °C. The Sun's core is about 15 million.
Their answer is PRISM, a spinning magnetic mirror concept with roots at Princeton. It's still a concept, not a working reactor.
Would you bet on the harder fuel? Tell me below 👇
Source: borealisfusion.com
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