"High-altitude winds between 1,640 and 3,281 feet (500 and 10,000 meters) above the ground are stronger and steadier than surface winds. These winds are abundant, widely available, and carbon-free.
"The physics of wind power makes this resource extremely valuable. “When wind speed doubles, the energy it carries increases eightfold, triple the speed, and you have 27 times the energy,” explained Gong Zeqi "
To be fair everything but nuclear is just indirect solar power (and if you count other stars besides just Sol, even fission kinda is)
Edit: And I guess geothermal isn’t really solar power either, that’s residual heat from formation of the planet
Tidal too. Slows the Earth’s rotation a minuscule amount more than usual.