Setting the objective to zero

[Simon Schneider]

Hi Ray and everyone who is deep enough into the subject.
Assuming I set all the coefficients and startup/shutdown costs in de 
mpc.gencost field to zero that means I get an objective function equal 
to zero, right?
When I run an optimal power flow afterwards, on which criterion ist the 
optimization based?

I´m guessing the calculation is then a conventional power flow obeying 
also the inequality constraints. Is that correct?

regards
Simon