"No solution returned"

[Tjerk]

Dear TIMES community,

When running my model with some export constraints I got an error from FE saying "no solution returned". The list file (see attached) tells me the LP status is: dual objective limit exceeded

The only thing I changed is adding an upper bound on the export of crude oil. This because even when I change the price to zero it keeps on exporting oil (there are no constraints on exporting oil). To me, it sounds like the model is forced to export oil to fulfill it's needs. However, I have no idea why. Does someone have experience with this problem?

Best regards,
Tjerk

[Antti-L]

You could try running the model by changing the Cplex options to use the default lpmethod (in cplex.opt):

scaind 0
rerun yes
iis yes
lpmethod 0

That should give you more information about the infeasibility from the the Cplex Infeasibility finder (it may take some time). The information will be written into the listing file, and it gives the constraints that are violated. It should give you a much better idea of the problem.  I have solved many infeasibility issues by utilizing the Infeasibility finder.