21-06-2019, 10:50 PM

(21-06-2019, 08:44 PM)Antti-L Wrote: Welcome to the ETSAP Forum!

TIMES is normally solved as an LP, and so I guess you are using some of the MIP extensions: lumpy investments (DSC) or discrete unit commitment (DUC)?

"Integer solution" probably refers to a MIP solution not proven optimal. To make sure that the solution is optimal, you should set the MIP optimality gap tolerance to zero. You can do it in GAMS or in the solver option file. Under VEDA, you can find the GAMS Options section in the Control Panel, and there the OPTCR setting, which stands for the relative optimality gap tolerance. Putting zero (0) there should be sufficient. The default value is 0.1 in GAMS, meaning that a 10% gap to the calculated best possible solution is sufficient for termination.

Dear Antti,

I am running just LP (using barrier), no DSC or DUC, but I see from the DOS run screen that indeed MIP is started, I do not know why. And in my options screen OPTCR is gray-ed out. So I cannot set a zero unless I activate DSC or DUC.