Stronghold digital https://zeiner.com/

own the power plant, use waste coal (glob piles). and have option to sell electricity to the grid if mining is unprofitable

In today's bear market, obviously the one that has the greatest efficiency (J/TH, ... the amount of electricity consumed per TH/s).

But you pay for that in CapEx (CapEx/TH).

If you are looking solely at J/TH, then the Antminer S19 XP has the best efficiency.

ASIC Index Data https://data.hashrateindex.com/asic-index-data

assuming you're inquiring on miner hardware. this site is handy:

adjust your electricity costs at the bottom of the site

then type ' sha-256 ' in the search box to filter by bitcoin capatible miners

The best profitability mainly depends on electricity costs! But the highest efficiency probably always the newest antminer I guess?

TI-86 calculator