I'm studying Physics at the moment and Prof. gave us a printout of a textbook last week stating that the internal of the sun generates approximately 150 W / m³ on average. That's about as much as a compost pile, so, not very much. The sun only generates enormous amounts of power because it's so huge. In other words, reproducing fusion on Earth might actually not be very efficient.
this post was submitted on 21 Jan 2025
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Yeah that is not how that works
The sun is enormous, yeah, but fusion only really happens at the core. A very tiny fraction of the sun is doing the fusion, the rest jlgets heated up, makes gravity and such, bit doesn't really do anything of interest energy wise.
Fusion creates a shit tonne more energy than 150w/cm3. Heck, you've never seen what a nuke does
No, OP is right - or rather, OP's physics professor. There's different kinds of fusion, though, and nobody's suggesting we do the exact same kind here on Earth (we basically can't).
Fusion creates a shit tonne more energy than 150w/cm3. Heck, you’ve never seen what a nuke does
That's power density (Watts). Multiply by 10 billion years to get energy density.
Different kind of fusion. Don't forget hydrogen bombs have been around for decades, right? They're just not very controlled and harnessable.
To the sun's credit, it's 4.5 billion years in and it's still got plenty of juice left to go.
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0 theoretical hope for fusion energy to ever provide electricity under 30c/kwh. These are hot plasma experiments, which could be used to produce mass HHO from water vapour at just 2200C-3000C, even if endothermic. Can get energy from concentrated solar mirrors or just PV solar if plasma is used. Cooling magnets is a huge energy drain. HHO provide the highest turbine energy gain, though a net gain pathway is just slightly more in reach than fusion.
Yes but do you concur?