Good morning,
I am sitting and trying to model the use of a CHP plant in my process, where I managed to collect the electricity and heat overflow in a storage place. Now I would like to use this waste el. and heat to minimise the total demand from the CHP plant. This I need to do at each process where the el. and heat is needed. However, at some point is the storage at an end and at that point, I receive the warning "negative stocks are not allowed". How do I assign the storage a variable that cannot be <0?
In my user defined functions I have to assign how much I want from the waste storage but I cannot see the present amount of the storage.
E.g. Heat from CHP=Heat demand for process - waste heat from CHP*IF(waste heat from CHP >0)
Thank you for your consideration,
Victor Norberg
