At last you write a somewhat positive story about solar, thanks for that.

As for how the company you are promoting are using it, they are not doing so well, it seems to me, they will run into the same problems as have been encountered in Vietnam (Though in my opinion, those are much better problems to have, than the ones we currently have, by us having nowhere near enough solar installations)

The remedy to the Vietnamese problem of having too much solar for the grid to handle Is not standard batteries, nor even any work to Grid infrastructure.

The excess solar power they have actually supersedes all requirements for power of any other kind, given they can scale up the solar even further, the function and power requirements of the grid itself are redundant. The Vietnamese grid is no longer needed, in the presence of all that solar energy. The grid itself has become bullshit industry.

A hydrogen electrolyzer and hydrogen fuel cells at each solar installation fixes all problems.

I've explained more here:

https://eric-bott.medium.com/the-beginning-of-the-end-for-grids-85192e6574bb