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WJW

Trick question! Space based solar derives all its energy from fusion anyway.

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This is the argument Elon uses in favour of solar - “we already have a giant fusion reactor in the sky”

lol then so does all solar terrestrially

So it does. That was not an option in GPs post though.

And so does terrestrial wind, hydro, coal, oil and gas. All ultimately came from the sun.

Only uranium proudly stands apart.

And uranium also comes from nuclear reactions before/outside our planet. In the end, we only use current or stored production of nuclear cosmic energy coming from E=mc2 isn't it ?

https://world-nuclear.org/information-library/nuclear-fuel-c...

Hmm.... tidal power comes from the Moon gravity interacting with Earth. And the Moon was created as a result of an impact of Earth by a large mass early in Solar System's history. So ultimately it is derived from the potential energy of the cloud of gas that coalesced to create Solar System, and not from any fusion or fission inside Sun or other stars.

The energy of uranium is ultimately sourced from gravitational potential energy (of collapsing stellar cores or merging neutron stars), not from nuclear energy. Indeed, the process of converting the iron of a pre-collapse stellar core to uranium is highly endothermic from a nuclear perspective, as iron is the lowest energy state of nuclear matter.

> Only uranium proudly stands apart.

Well, kind of. That comes from fusion reactions in _other_ suns.

Geothermal and tidal energy are also not fundamentally based on local solar power.

Though one might argue that they're also ultimately stellar-based power in the sense that in the case of geothermal energy both the residual gravitational thermal heat and heavy-element radioactive decay, and in the case of tidal power, the formation of our own proto-solar-system nebula were themselves based on earlier-generation stars.

But then so is nuclear fission based on heavy elements such as uranium, plutonium, or thorium.

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