How do energy solutions interact with each other in Open Studio?

asked 2021-08-26 16:17:54 -0500

gspiridakis gravatar image

updated 2021-08-27 04:07:25 -0500

So i have modeled a building and I am applying energy solutions to observe the evergy savings of each solution.

For the first energy saving solution i add insulation to the external walls of the building (Solution A). For the second one i reduce the infiltration of the building (Solution B). For the third and last one, i combine the two previous solutions, so i end up with a building with insulated walls and reduced infiltration (Solution AB).

When checking the savings of each solution i realized that the energy savings of solution A + the energy savings of solution B are less than the energy savings of solution AB. Does anybody know why that is?

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Which numbers are you looking at exactly? Have you looked at hourly (or even 'Detailed' timestep) results to see when you actually get a discrepancy? Do you have AC for the summer in your building? I'm trying to understand what interactivity between both measures could explain it.

Julien Marrec gravatar image Julien Marrec  ( 2021-08-27 03:26:25 -0500 )edit

I am looking at the total electrical energy consumption which comes from the electrical devices, lighting and the AC. Yes i have looked at more detailed timestep and it seems that AB solution savings are closer to A+B savings in the winter. In the summer AB savings are slightly lower than A+B savings.

The AC is set at 26C in summer and 22C in winter although it is fixed for all the above scenarios. I can't seem to understand how these two solutions interact with each other that leads to that decrease in the savings.

gspiridakis gravatar image gspiridakis  ( 2021-08-27 03:42:45 -0500 )edit

This is a diagram that i made with the savings of A,B and AB where A is B and B is D in the diagram and also the Utilizability Index which is basically (AB savings)/((A savings)+(B savings))

gspiridakis gravatar image gspiridakis  ( 2021-08-27 03:52:41 -0500 )edit

Is this just the impact of thermal lag creating slightly different interior/exterior temperature gradients, which in turn partially determines the magnitude of conduction and infiltration. Specifically, if the HVAC perfectly supplied enough energy to maintain the 26C setpoint AB would equal A+B, but the impact of thermal lag should prevent that, creating: deviations from the 26C; setpoint, deviations in the temperature difference, and thus deviations in the magnitude of A and B when modeled together.

saeranv gravatar image saeranv  ( 2021-08-28 12:29:34 -0500 )edit

I get what you are saying and it is something that i had on my mind but answer me this. Thermal lag applies to all solutions (A, B and AB). What makes thermal lag in Solution AB different from the thermal lag happening in A and B? That is what i am trying to figure out.

gspiridakis gravatar image gspiridakis  ( 2021-08-28 14:09:57 -0500 )edit