> You may go back to your freshman physics textbook.
I may, but I live in a country that doesn't use the word freshman, so I don't know which year physics text that would be.
I assume from context you were meaning to refer to gravitational potential energy, which is generally represented as ∆U=mg∆h (change in gravitational potential energy equals mass times gravity times change in height). The variables you used (E=Fx) would mean energy equals force times (variable). From dimensional analysis the variable would have to be units of length (m), however it clearly only applies in the vertical dimension so it's better to use a specific variable like ∆h
Regardless, energy storage via gravitational potential energy (i.e. pumped storage) has been in use for about a century, and still makes up a rsmall proportion of grid operations. It has very specific requirements that aren't available everywhere. It's not an end-all solution for energy storage.
