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Equivalent thermal R and C of house

asked 2017-06-13 12:11:48 -0500

Prateek gravatar image

updated 2017-06-16 03:11:43 -0500

I have developed an EnergyPlus house model using BEopt. I am trying to use a simplified HVAC model for the optimization purpose. Though the model may not give exact result as detailed EnergyPlus model, I am using this model for optimization only. For the model, Equivalent thermal resistance (R) and equivalent thermal capacitance (C) of the house is required. How do we estimate roughly, the parameters R and C. The model of heater when on is image description The model of heater when off is image description

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answered 2017-06-16 03:22:25 -0500

updated 2017-06-16 03:22:39 -0500

Q is the heater output right? I haven't spent more than 30 seconds thinking about it (so less time than writing this), but I don't really see any other way than getting the model output as time series and fitting your model against it to get your parameters. Your dependent variables are zone temperature and heater output (or Zone Air System Sensible Heating Energy maybe), your independent ones are your R and C.

Across a full year simulation, you should have more than enough datapoints to fit your model, but there's a chance your fit will be terrible, and you will probably need to downsample (aggregagate over longer periods of time).

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Asked: 2017-06-13 12:11:48 -0500

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Last updated: Jun 16