Methane or Acetylene Gas, a way to store solar energy

[Peterae]

So if we were to take Calcium Hydroxide and carbon and use an electric arc we can produce solid Calcium Carbide.
If water is added to Calcium Carbide we get acetylene gas and a solution of calcium Hydroxide.
The cycle could be repeated using the Calcium Hydroxide produced when dried and re added to the first step.

See video here
https://www.youtube.com/watch?v=xSAziTIHs3w

If instead of using Calcium Hydroxide we were to instead use Magnesium hydroxide or aluminium hydroxide, i wonder if also the Aluminium Carbide or Magnesium Carbide would form, if so when added to water we would get Methane Gas instead of Acetylene Gas.

So it maybe possible to store our Solid Magnesium/ Aluminium Carbide that is made when the sun is out and add water to produce Methane any time we require it.