Does all our energy on Earth come from the sun?

It could be, but it's not. A big part is nuclear decay, strangely enough. Some is from primordial heat, and some is from the motion of the core, but mostly from regions rising and falling, not rotation.

Hypothetically those would average to O as they strike randomly though right?

But it sounds like, based on other comments, those things are from stars too, right? Like the sun caused the formation of our planet. It also contributes to tidal forces. And radioactive materials also came from other stars if not our own star. Right?

Uh, I'll find one, and edit. It confused the shit out of Victorian scientists, because they had a good guess how old the Earth is from biology, and had thermodynamics, but it was telling them volcanism shouldn't still be happening.

Edit:

Wikipedia mentions it in the geothermal article, but the source is a textbook, and who has time and/or money for that? There's also the article on the age of the Earth. Ah, here we go, in the article on Earth's internal heat budget. Somebody also linked a paper on it elsewhere in this thread.

These give slightly different numbers from each other, but the gist is that radioisotopes (Uranium, Thorium and Potassium being the primordial ones) account for at least half.

It gets both slower and further away (to stay in orbit) every year, by like 2 cm IIRC.

If you could go back a couple billion years it would be huge in the sky. There was even a period, called the Jatulian, where you might not have asphyxiated in the early atmosphere. There wouldn't be much else to look at, though, and just your skin germs would be futuristic enough to completely change the course of life on Earth, once they get into the environment.

Without angular momentum it would have fallen back down to the Earth instead of going into orbit. It's the orbit specifically that powers the tides, not just it being there.

But yeah, you're right. Beyond providing the materials dust was not involved.

They said “tidal forces,” not “tides.” Tidal forces refer to the differential of gravitation between two points on an object. It applies in any situation where gravity is a factor, although typically only very large massive objects experience noticeable effects. That said, the concept of spaghettification (objects being stretched out as they approach a black hole’s event horizon) is based on the fact that tidal forces near a black hole would be so enormous they would be observable for even small objects like people.

Hm. Touche.

If it doesn't have to be energy that's used as such, there's more answers.

Neutrinos stream through us each moment at a flux pretty similar to sunlight. Day and night; they sail right through the Earth for the most part. Most of it is from the sun's core (directly), but some of it is from distant cosmic monsters like supernovae and jets whipping around black holes, and some of it escapes from nuclear reactions on Earth, in particle accelerators and nuclear generators or from decays in nature.

Gravitational waves from distant black hole mergers have been detected on Earth, and they do carry energy.

Meteors hit the Earth, and sometimes they carry enough energy with them to cause damage, like in Chelyabinsk.

You mentioned cosmic rays. The most energetic ones far exceed the energy of anything our accelerators produce, and it's still a mystery where those unusually powerful ones come from.

Stars give out a lot of electromagnetic energy in the form of radio, microwave, infrared, ultraviolet and x-rays as well as visible light, and probably gamma rays too, although I haven't heard anything about that one. Many frequencies of light are heavily or even fully absorbed by the upper atmosphere of Earth, which is part of what makes space telescopes necessary.

Lighting strikes on Jupiter are very noticeable as noise on some radio bands. I'm not actually sure how much of the wind that powers that is the Jupiter equivalent of geothermal, and how much is ultimately from sunlight. I'm guessing it skews to the latter, though.

I guess it depends on how far back you want to go. The sun wouldn't exist without gravity.

What's really interesting is that "what goes up, must come down" doesn't hold at the scale of the universe. A naive thinker might imagine big bangs happen in cycles, but in fact this doesn't appear to be the case, because space itself is expanding faster than galaxies are falling back together. And it's not just faster now, but it's accelerating! At some point, space will be expanding faster than the speed of light, and because of that, the entire universe will disappear from our view.

Despite that, the Milky Way galaxy is still close enough to the Andromeda galaxy that they'll collide in about 5 billion years, so don't worry, there's still interesting things to come! If you want to see it, though, you'll need to be somewhere other than Earth, because by that time the Sun will have advanced in its life cycle enough to render Earth completely uninhabitable by all known forms of life.

Brane cosmology suggests the collision of two branes can result in a big bang event, but yes, that is beyond an event horizon.

So, first off, I'm definitely not arguing this would be a feasible way to get energy in a practical sense in the real world.

But, it wouldn't be a perpetual motion machine. It'd produce less and less energy as the Earth ran out of angular momentum, ultimately approaching zero.

I don't think I'll do the monster math on this, but my gut tells me one could technically and theoretically (not so much in practice) get more energy out of that than it took to get the weight up there. (It might be that the Moon would limit how much energy could be got out of this scheme as well, but I think even with the Moon involved, I think it could still be a net energy gain.) That said, without running the numbers, you might well be right!

What I posted would take energy from the angular momentum of the Earth rotating on its own axis, not the (angular?) momentum of the Earth revolving around the Sun.

Honestly, I'm not 100% sure the right way to talk about where the Earth's angular momentum about its own axis came from. I want to say gravity while the Earth coalesced from dust/gas, but I'm not sure that's quite true because I think the gravity would only kindof "concentrate" the angular momentum that was already present in the gas/dust that was already present in the cloud. (Like, when an ice skater pulls their arms toward their body and speed up, that doesn't add energy or momentum to the system that is the ice skater.)

So, maybe it's more accurate to say it's kinetic energy from the Big Bang and/or supernova(s?) that produced the gas/dust that eventually formed the Earth?

But I'm pretty sure this scheme would get energy from a source that wasn't ultimately from the Sun.

I mean ya okay I see that. But still very neat that all energy in every form we have can be traced back to a star if not our own star. That’s so interesting! Let’s get started on the Dyson sphere.

Nuclear materials were formed in supernovas. They wouldn't exist in the first place without a star.

Well, yeah, sure. But that star is not the Sun.

Earth wouldn't have coalesced without the sun in the middle. Otherwise we'd still be a gas blob.

I mean, sure? It wouldn't be a gas blob, but it would be a very different system. But that still has nothing to do with it -- even if the gravity of the sun influences how the earth coalesces, it's still not where the thermal energy of the core came from. That came from the potential of the dust itself.

I agree with hydro, but you're wrong about geothermal. Tidal forces caused by the Sun are minuscule compared to that of the Moon. Also, Earth still has a decent amount of latent heat caused by its formation.

Geothermal is ultimately caused by the gravity of the sun affecting the earth.

No, that's how it works on the Jovian moons, but Earth's interior is heated by some mix of radioactivity and retained primordial collision heat.

Well there is still nuclear, piezoelectric, and kinetic, at least.