Hi,
I am working on a model that simulate the long-term investment behavior for electricity market. In order to betwer simulate this behavior, I need to calcualte the profit by simulating the price under different demand load for each hour of the year. So, I need to build the load duration curve, it is defined as the variation of a certain load in a downward form such that the greatest load is plotted in the left and the smallest one in the right. On the time axis, the time duration for which each certain load contiunues during the day is given.
To avoid unnecessary complexity in the exemplary calculations , a linear LDC with an initial peak load and a minimum load at the start of the simulations is adopted. it can be analytically expressed as:
L(t) = (Lmin(t) - Lmax(t))*d + Lmax(t).
My question is if I define t as years, then d as load duration is hour of year. At each time t, there will be a LDC.
and taking into account other factors, the Lmin and Lmax will also change over time.
We can simply understand d as an interval [0,1] (Analogy [0, 8760]),
Does vensim have any function to solve it?
or, this question is needed to build two models to interconnect each other?
Thank you for your attention!
Does Vensim embed loop intervals?
Re: Does Vensim embed loop intervals?
I am so sorry that I ask the question twices.
I resubmitted the question due to typographical erros.
Say sorry again to everyone.
I resubmitted the question due to typographical erros.
Say sorry again to everyone.
Re: Does Vensim embed loop intervals?
No problem - we can delete one. Is this the better copy?
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Re: Does Vensim embed loop intervals?
I think the thing to do is to discretize the LDC into a number of segments, represented by an array dimension. Then you can compute utilization of each plant type in each segment. Then the price is the highest-cost plant with nonzero utilization in the segment. (The allocation functions might make this really easy.)
Then you can SUM() over the array to find each plant's utilization, revenue, etc. over the year.
Then you can SUM() over the array to find each plant's utilization, revenue, etc. over the year.
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Re: Does Vensim embed loop intervals?
Hi, thank you for your reply.tomfid wrote: ↑Thu Dec 12, 2019 2:48 am I think the thing to do is to discretize the LDC into a number of segments, represented by an array dimension. Then you can compute utilization of each plant type in each segment. Then the price is the highest-cost plant with nonzero utilization in the segment. (The allocation functions might make this really easy.)
Then you can SUM() over the array to find each plant's utilization, revenue, etc. over the year.
From your suggestion, I build an example model in the attachment, just focus on the discretize the LDC.
I set the load duration(d) to days, so I get 365 line and the software has begun to become sluggish. I am not sure if the software can work normally if the d is set to hours and the time step is set small.
Re: Does Vensim embed loop intervals?
Does it make sense to have a small time step in a long-term capacity model? Or if it does, could you then dispense with the array and observe actuals?
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