A question about Allocate available function

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kong17
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A question about Allocate available function

Post by kong17 » Mon Nov 25, 2019 3:23 am

Hi,
I am preparing to build a model of the electricityt market, which has a question about merit order of capacity.
It is a typlical problem of building a supply curve and dispatching.

For example, I have 3 suppliers: 10(a), 20(b), 5(c)
The supplier has different costs: 1, 2, 3
Demand: 29
Price: 2.8
The solution: due to the price is large the cost, the prower is generated. So, a provides 10, b provides 19.

From Vensim help, I found the Allocate function to solve it.
But, I analyze a long-term market dynamics. So, the demand will be changed by other factor like demand growth rate. At the same time, the supply also will be changed, because of the decommissioned old capacity and new capital investment for capacity.

Because I rarely used subscripts before, I want to show the change in growth directly in the formula.
But, it said the error: ONLY NUMBERS SEPARATED BY COMMAS ARE VALID IN THIS CONTEXT
Image
So, I was wondering how to solve it?
Thank you very mcuh!
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JudeChen
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Re: A question about Allocate available function

Post by JudeChen » Mon Nov 25, 2019 5:40 am

This attached model would mimic what you are say you want to achieve. There is a lot more that goes into modelling the electricity market. Good luck!

Do note that this is a quick job so I didnt align the units.

Reading the documentation and what others have posted before about these functions are very useful. Do note that priority component uses -Supplier Cost as highest value of what is sent into the function gets top priority.

https://www.vensim.com/documentation/fn ... ilable.htm
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tomfid
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Re: A question about Allocate available function

Post by tomfid » Mon Nov 25, 2019 3:45 pm

The immediate problem here is that you can only use a comma-separated list for constant values (i.e. numbers).
https://www.vensim.com/documentation/21265.htm

kong17
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Re: A question about Allocate available function

Post by kong17 » Wed Dec 11, 2019 9:54 pm

JudeChen wrote:
Mon Nov 25, 2019 5:40 am
This attached model would mimic what you are say you want to achieve. There is a lot more that goes into modelling the electricity market. Good luck!

Do note that this is a quick job so I didnt align the units.

Reading the documentation and what others have posted before about these functions are very useful. Do note that priority component uses -Supplier Cost as highest value of what is sent into the function gets top priority.

https://www.vensim.com/documentation/fn ... ilable.htm
Thank you very much. So sorry that I reply so late.
From your hint, I found solution. Thanks again.

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