Side Channel Analysis (CorrPA), comparison between HW-results and measured power traces
You should use the value you found (in watt). Try to have a look at this  file, it's really well explained in my opinion. If you look for page 21 for instance, you'll see that the plaintext produces a certain waveform; then, after the hypotesis and the S-Box output, the correlation is clearly done with the power model obtained and the value of the traces (page 23)