If you underclock them with
Braiins OS you can even add more of them. By raising efficiency you can easily lower that consumption to under 820w each (@10T)... You could put 48 S9s, maybe some more if a few have damaged boards.
480THs vs 390THs using the same 40kW...
Make sure you check more sellers, i have seen S9s at $150 each...
PLUS, under-clocking tends to make them run cooler and last longer.
Thank you for this idea it was really helpful.
150$ S9s? Please do you have any link or contact? All what I've found it's 385usd per unit.