A:Answer Clearly "goob" and "worksforgeeksquad" missed the part about this laptop where it clearly states "2TB HDD + 512GB SSD".
To answer your question, you would not save any power by powering down the 2TB HDD (which uses platters, not an SSD.) I'm going to yank the 2TB drive out and simply replace it with the SSD drive from my old laptop, however, until I need more room.