Blackouts (Ho Chi Minh City)

I have a question. My husband and I are considering a move to HCMC, but we want to find out as much as we can, becfore we make a decision. Naturally. Anyway, I have heard about scheduled blackouts in Protected content temperatures...and that this is not unusual and can be a real challenge. About how often does this happen, and for how long at a time?

Thanks!!

Lori Souza