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I agree. I enjoy anything she produces that is physics-related but the social commentary and science topics outside her area of expertise are hit-or-miss. I als

I agree. I enjoy anything she produces that is physics-related but the social commentary and science topics outside her area of expertise are hit-or-miss. I also think she opens herself up to audience capture, especially now that she's being funded directly by viewers, and that concerns me.

Retric 3y ago
She also made some significant errors in physics videos. One example is she calculated the power output of fusion reactions as energy created by fusion * heat to electricity conversion efficiency. However, energy that’s heating the plasma should also recoverable at the same conversion efficiency. Largely irrelevant a Q=1,000 but it plays a major role in what Q is breakeven and what Q is economically useful. Not on the surface such a big deal, but a sign she should reach out more to actual experts in these fields.
- jiggawatts 3y ago
  So… she’s correct in the industrial regime that matters, but technically incorrect in the experimental regime where the energy is not recovered?
  - Retric 3y ago
    If she was talking about very high Q then it wouldn’t be a major issue, but she was specifically referring to the regimes where it was important. Aka energy breakeven and minimum economic viability. It also explains why Q is formulated in terms of energy added to the plasma vs energy gained from fusion which she didn’t understand. This formula for Q ends up being a term in the equation for economic viability, but she attacked it as if such a formulation was misleading. Basically the total energy spent on the facility including cryogenic cooling, pumps, etc matters + Q as defined by fusion experts + fusion output energy + conversion energy lets you find the total net energy gain which you then compare with the cost of the facility to find economic viability. Roughly, [ (Fusion energy) * (1 + 1/Q) * (conversion efficiency) - (Total energy use by facility) ] / (cost per hour of operation) = energy per dollar. There are other ways you can calculate that same number, but they require a lot more details.

Retric 3y ago

She also made some significant errors in physics videos. One example is she calculated the power output of fusion reactions as energy created by fusion * heat to electricity conversion efficiency. However, energy that’s heating the plasma should also recoverable at the same conversion efficiency. Largely irrelevant a Q=1,000 but it plays a major role in what Q is breakeven and what Q is economically useful. Not on the surface such a big deal, but a sign she should reach out more to actual experts in these fields.

jiggawatts 3y ago
So… she’s correct in the industrial regime that matters, but technically incorrect in the experimental regime where the energy is not recovered?
- Retric 3y ago
  If she was talking about very high Q then it wouldn’t be a major issue, but she was specifically referring to the regimes where it was important. Aka energy breakeven and minimum economic viability. It also explains why Q is formulated in terms of energy added to the plasma vs energy gained from fusion which she didn’t understand. This formula for Q ends up being a term in the equation for economic viability, but she attacked it as if such a formulation was misleading. Basically the total energy spent on the facility including cryogenic cooling, pumps, etc matters + Q as defined by fusion experts + fusion output energy + conversion energy lets you find the total net energy gain which you then compare with the cost of the facility to find economic viability. Roughly, [ (Fusion energy) * (1 + 1/Q) * (conversion efficiency) - (Total energy use by facility) ] / (cost per hour of operation) = energy per dollar. There are other ways you can calculate that same number, but they require a lot more details.