Only alternatives that I'm aware of:

• solar cells (converting photon energy into electricity)
• acid batteries (converting chemical energy into electricity)
• peltier devices (converting heat differential energy into electricity)
• induction (converting electrical energy into electricity on a different circuit)
• bioelectricity (using biochemical energy to produce electricity)
• static buildup (using friction between various materials to produce a voltage differential)

I think there's a way to use lasers to generate electricity, too.

It's all variations of "make things spin."

Either by heating up water so steam makes thing spin, using wind to make thing spin, or moving water to make thing spin.

I am willing to bet if you watched photo cells on solar panels under a microscope, the light would make something spin.

solar cells have no mechanically moving parts

ironically, large grid tie systems are starting to "emulate" the spinning mass behavior of turbine generators, since there's an exponential failure issue waiting to crop up if you aren't careful, as texas has already learned, a very significant part of your solar generation can just, go offline, if it decides grid conditions aren't suitable, which can lead to LARGE drops in power production and frequency, which is likely to kill even more generation.

So the solution is to make it emulate the physical mass tied to a turbine, or at least, more generously provide power in fault like conditions, to prevent this sort of exponential breakdown of the grid. You could of course, use a large spinning flywheel to regulate grid frequency, as is being used in a few places right now. I'm not sure how popular that is, outside of wind energy. It's likely to get more popular though.

weird little side tangent, but the frequency of electricity on the grid is essentially directly tied to the rotational speed of all turbines currently on the grid, meaning there is a very large inertia in the grid frequency, it's weird to think about, but makes perfect sense, and it provides for an interesting problem to solve at large scales like this.

Batteries are really fucking cool btw, the fact that you can just chemically store electricity, and then use it, is really fucking crazy. The fact that it's the most accessible technology is also insane to me. But maybe it's just the adoption being the way it is.

It is not the top one in the typical usage of the word "nuclear energy." Sure, it is nuclear energy, but that normally refers to electrical infrastructure, not nuclear weapons. Nuclear electricity is pretty much always just heating water up in a safe and controlled manner, and using that to spin a turbine.

Hot salt is where it's at