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All Topics | Topic "Importance of order of addition of transmission links"
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Author Message
Mr. Adil Mounir

Subject: Importance of order of addition of transmission links   
Posted: 7/28/2020 Viewed: 1932 times
I made an experiment where I would add transmission links from 4 rivers to 1 demand node. Each time, I would obtain different results despite having the same parameters. I have made a video to better illustrate my confusion. Here is the link to the video:

https://www.youtube.com/watch?v=j2lBWmPpBFg&t=92s
Mr. Jack Sieber

Subject: Re: Importance of order of addition of transmission links   
Posted: 7/28/2020 Viewed: 1931 times
Dear Adil,

WEAP does not try balance or make equal the amounts supplied from sources with the same supply preference (e.g., River 1 and River 2), as long as all other constraints are satisfied. Therefore, I am not surprised that the allocations from those two sources can vary based on their creation order – this would affect the order in the equation matrix created for the linear program solver used by WEAP, and because it has many degrees of freedom in solving the allocation equations, the results can be arbitrary. (That’s just in the nature of LP solvers when there is not just one unique corner solution.) However, I am surprised that the allocations from River 3 and River 4 vary. Because the preference for River 3 is higher than River 4, WEAP should allocate as much water as possible from River 3, and only then allocate from River 4.

By the way, which solver did you use, lpsolve or XA?

Can you please send me your WEAP area so that I can test it? The easiest way to do this is from WEAP. On the main menu, go to Help, Send Email to WEAP Support. Make sure to select "Attach area" so that WEAP will attach your area to the email to me.

Best regards,
Jack

Topic "Importance of order of addition of transmission links"