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Comment by AutumnCurtain | Hacker News Reader

>Early reports estimated that 250 kilo-joules of energy was deposited on the target (roughly 2/3 of the energy from the beams), which resulted in a 1.3 Megajoule output from the fusing plasma.

Incredible progress over where they were just a couple years ago.

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For reference: 1 MJ = 0.277778 kWh.

Not trying to knock the progress made or anything like that, I just needed the conversion to a more familiar unit in order to appreciate what sort of scale they're talking about.

When thinking of this amount of energy in kWh it seems small, but if this is deposited by lasers in a small fraction of a second it seems like a huge amount of power delivery.

Yeah, the time scale and volume of where it's happening matters a lot.

It's like in fission when you read about reactions giving net energy of X MeV. If you convert that to even Wh, let alone kWh, it's an incredibly small number. But when you start multiplying by the number of atoms in a fuel source, it starts adding up VERY quickly.

Though, when 1 MJ is generated in a fraction of a second, that does mean its instantaneous output was in the MW+ range

Unfortunate, though, that NIF can't do continuous generation by design. It's good for learning from and validating stuff instantaneously, but it's almost certainly an architectural dead-end otherwise.

Hard not to see it as a laser weapons program wearing power-plant clothes.

Yeah, the idea is to do like dozens of these explosions per second, like in an internal combustion piston engine. There was a conceptual design for a fusion power plant based off of laser inertial fusion like NIF called LIFE.

Works kind of like the EUV light sources TSMC uses to make the highest end computer chips, except a fuel pellet instead of a drop of tin. Like so: https://en.wikipedia.org/wiki/Laser_Inertial_Fusion_Energy

Also 1 MJ = 250 calories. So like a pizza slice.

calories or kilocalories?

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