Depends on the device. Q_plasms > 150 iirc is the estimate for MCF fusion. The NIF lasers take in way more energy than they put into the pellet, so that I thin

Depends on the device. Q_plasms > 150 iirc is the estimate for MCF fusion. The NIF lasers take in way more energy than they put into the pellet, so that I think you want something like Q_plasma > 10,000 iirc. Iirc most engineers use a different Q, which refers to all in energy, so Q > 1.5 ish is enough