How do I manually “shut down” an hard drive without plugging it out?

Question 1

I am connecting 1-2 hard drives via E-SATA. Using Windows, is there an option to force “shutting down” that hard drive (until it is needed again)?

Question 2

What you’re looking for is to ‘spin down’ a drive. Here is a similar question.

If you want to disable drives with the command line, you can use DevCon:

devcon disable <hardware id>

Using the device manager:

Right click on disk > disable

Answer