JuMP design question

Specific Domains Optimization (Mathematical)
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Hi,

I am building a model which is made up of smaller models. The smaller model definition can be found here: JuMP: which solver should I use for my problem?

For context, the model linked above is a heat pump h which consumes a certain electrical power P_t^{(h)} at each timestep t.

Now I also have an electricity grid model defined in JuMP, which consists of buses and lines. I want to add a heat pump to each bus, electrically this is simple but I am not sure how to do it in JuMP.

I guess this comment JuMP Multiple Models Design Question - #2 by odow would be the right way to include the submodels in the larger model? It’s an older comment so I am not sure it still applies.

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Read Design patterns for larger models · JuMP

You cannot embed models inside other models.

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I read that, but I cannot make the connection from the knapsack example to my problem. There is a lot happening in that tutorial I can’t figure out which part of it I need.

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I’d say you need all of it :smile:

Perhaps you could post a small example of what you would like to do, and then we can show how it should be written.

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Okay that’s disappointing, I thought I could just add one model to the other. That would save me a lot of time and rewriting :slight_smile: there should be a level of modularity possible here I think.

Seems like the main task now is to rewrite the heat pump model into functions that add the constraints, variables and objectives separately to the ‘main’ electrical model?

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Yes. Exactly this.

Don’t build subcomponents as JuMP models. Build them as function which add components to an existing JuMP model, and use either a naming convention, or an external data structure to manage the relevant variables and connections between components.

If you’re building an energy system model, take a look at the design of PowerSimulations.jl, and read through (and watch the videos) of Open Energy Modeling at JuMP-dev | JuMP

I’ll point you particularly to:

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I get it, thanks for explaining. Submodels are possible in pyomo, I was expecting a similar mechanic in JuMP :slight_smile:

Thanks for the resources, appreciate the help. It’s becoming clearer to me what to do now.

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We’re discussing this in Explore namespace ideas · Issue #3791 · jump-dev/JuMP.jl · GitHub

Note that its a different design choice. But Pyomos approach is not obviously better. There are a number of trade offs to consider. JuMPs approach is different but people have demonstrated you can easily build large and highly flexible models with it.

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