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### Shading control with variable transmittance schedule

I am investigating a simple concept on the impact of dynamic shading on buildings thermal loads using energyplus. I am using the "Shading:Zone:Detailed" class to define my shading surfaces as part of hipped roof overhangs. What I need to do is simply to deploy the shade during summer and remove it during winter.

To test this, I considered 4 scenarios; a) No shading surface at all, b) fixed shade with no transmittance schedule, c) fixed shade with transmittance schedule = 1, d) fixed shade with transmittance schedule = 0 and e) shade with seasonal transmittance schedule (i.e. sch = 1 in winter and sch = 0 in summer). My analysis showed that cases (b) and (d) are exactly matching, cases (a) and (c) are slightly different (0.1% and 0.4% difference in heating and cooling respectively). When I apply case (e) the results are 1.5% higher in heating energy compared to case (a) and 3% lower in in cooling energy compared to case (d).

I realized that the reason could be due to the "DetailedSkyDiffuseModeling" algorithm option that is enforced when the transmittance schedule varies, and thus the results may not be comparable. However, I tried to use the "DetailedSkyDiffuseModeling" algorithm for cases (c) and (d) but that didn't change the results from what it is (i.e. using "SimpleSkyDiffuseModeling" algorithm. I also tried to use EMS to vary the transmittance schedule, I can see that the values are changing but the program ends up using the base schedule assigned in the "Shading:Zone:Detailed" class.

I came across this relevant issue and this on GitHub and looked at the comments by @Archmage and @JasonGlazer. I am not sure if the issue is resolved? and is there any workaround?

Thank you!

### Shading control with variable transmittance schedule

I am investigating a simple concept on the impact of dynamic shading on buildings thermal loads using energyplus. I am using the "Shading:Zone:Detailed" class to define my shading surfaces as part of hipped roof overhangs. What I need to do is simply to deploy the shade during summer and remove it during winter.

To test this, I considered 4 scenarios; a) No shading surface at all, b) fixed shade with no transmittance schedule, c) fixed shade with transmittance schedule = 1, d) fixed shade with transmittance schedule = 0 and e) shade with seasonal transmittance schedule (i.e. sch = 1 in winter and sch = 0 in summer). My analysis showed that cases (b) and (d) are exactly matching, cases (a) and (c) are slightly different (0.1% and 0.4% difference in heating and cooling respectively). When I apply case (e) the results are 1.5% higher in heating energy compared to case (a) and 3% lower in in cooling energy compared to case (d).

I realized that the reason could be due to the "DetailedSkyDiffuseModeling" algorithm option that is enforced when the transmittance schedule varies, and thus the results may not be comparable. However, I tried to use the "DetailedSkyDiffuseModeling" algorithm for cases (c) and (d) but that didn't change the results from what it is (i.e. using "SimpleSkyDiffuseModeling" algorithm. I also tried to use EMS to vary the transmittance schedule, I can see that the values are changing but the program ends up using the base schedule assigned in the "Shading:Zone:Detailed" class.

I came across this relevant issue and this on GitHub and looked at the comments by @Archmage and @JasonGlazer. I am not sure if the issue is resolved? and is there any workaround? I am using energyplus v9!

Thank you!

### Shading control with variable transmittance schedule

I am investigating a simple concept on the impact of dynamic shading on buildings thermal loads using energyplus. I am using the "Shading:Zone:Detailed" class to define my shading surfaces as part of hipped roof overhangs. What I need to do is simply to deploy the shade during summer and remove it during winter.

To test this, I considered 4 5 scenarios; a) No shading surface at all, b) fixed shade with no transmittance schedule, c) fixed shade with transmittance schedule = 1, d) fixed shade with transmittance schedule = 0 and e) shade with seasonal transmittance schedule (i.e. sch = 1 in winter and sch = 0 in summer). My analysis showed that cases (b) and (d) are exactly matching, cases (a) and (c) are slightly different (0.1% and 0.4% difference in heating and cooling respectively). When I apply case (e) the results are 1.5% higher in heating energy compared to case (a) and 3% lower in in cooling energy compared to case (d).

I realized that the reason could be due to the "DetailedSkyDiffuseModeling" algorithm option that is enforced when the transmittance schedule varies, and thus the results may not be comparable. However, I tried to use the "DetailedSkyDiffuseModeling" algorithm for cases (c) and (d) but that didn't change the results from what it is (i.e. using "SimpleSkyDiffuseModeling" algorithm. I also tried to use EMS to vary the transmittance schedule, I can see that the values are changing but the program ends up using the base schedule assigned in the "Shading:Zone:Detailed" class.

I came across this relevant issue and this on GitHub and looked at the comments by @Archmage and @JasonGlazer. I am not sure if the issue is resolved? and is there any workaround? I am using energyplus v9!

Thank you!

### Shading control with variable transmittance schedule

I am investigating a simple concept on the impact of dynamic shading on buildings thermal loads using energyplus. I am using the "Shading:Zone:Detailed" class to define my shading surfaces as part of hipped roof overhangs. What I need to do is simply to deploy the shade during summer and remove it during winter.

To test this, I considered 5 scenarios; a) No shading surface at all, b) fixed shade with no transmittance schedule, c) fixed shade with transmittance schedule = 1, d) fixed shade with transmittance schedule = 0 and e) shade with seasonal transmittance schedule (i.e. sch = 1 in winter and sch = 0 in summer). My analysis showed that cases (b) and (d) are exactly matching, cases (a) and (c) are slightly different (0.1% and 0.4% difference in heating and cooling respectively). When I apply case (e) the results are 1.5% higher in heating energy compared to case (a) and 3% lower in in cooling energy compared to case (d).

I realized that the reason could be due to the "DetailedSkyDiffuseModeling" algorithm option that is enforced when the transmittance schedule varies, and thus the results may not be comparable. However, I tried to use the "DetailedSkyDiffuseModeling" algorithm for cases (c) and (d) but that didn't change the results from what it is (i.e. using "SimpleSkyDiffuseModeling" algorithm. algorithm). I also tried to use EMS to vary the transmittance schedule, I can see that the schedule values are changing (by reporting the new schedule) but for the results the program ends up using the base schedule assigned in the "Shading:Zone:Detailed" class.

I came across this relevant issue and this on GitHub and looked at the comments by @Archmage and @JasonGlazer. I am not sure if the issue is resolved? and is there any workaround? I am using energyplus v9!

Thank you!

### Shading control with variable transmittance schedule

I am investigating a simple concept on the impact of dynamic shading on buildings thermal loads using energyplus. I am using the "Shading:Zone:Detailed" class to define my shading surfaces as part of hipped roof overhangs. What I need to do is simply to deploy the shade during summer and remove it during winter.

To test this, I considered 5 scenarios; a) No shading surface at all, b) fixed shade with no transmittance schedule, c) fixed shade with transmittance schedule = 1, d) fixed shade with transmittance schedule = 0 and e) shade with seasonal transmittance schedule (i.e. sch = 1 in winter and sch = 0 in summer). My analysis showed that cases (b) and (d) are exactly matching, cases (a) and (c) are slightly different (0.1% and 0.4% difference in heating and cooling respectively). When I apply case (e) the results are 1.5% higher in heating energy compared to case (a) and 3% lower in in cooling energy compared to case (d).

I realized that the reason could be due to the "DetailedSkyDiffuseModeling" algorithm option that is enforced when the transmittance schedule varies, and thus the results may not be comparable. However, I tried to use the "DetailedSkyDiffuseModeling" algorithm for cases (c) and (d) but that didn't change the results from what it is (i.e. using "SimpleSkyDiffuseModeling" algorithm). I also tried to use EMS to vary the transmittance schedule, I can see that the schedule values are changing (by reporting the new schedule) but for the results the program ends up using the base schedule assigned in the "Shading:Zone:Detailed" class.

I came across this relevant issue and this on GitHub and looked at the comments by @Archmage and @JasonGlazer. I am not sure if the issue is resolved? and is there any workaround? I am using energyplus v9!v9.1!

Thank you!

 6 retagged shorowit 7533 ●68 ●8 https://www.nrel.gov/b...

### Shading control with variable transmittance schedule

I am investigating a simple concept on the impact of dynamic shading on buildings thermal loads using energyplus. I am using the "Shading:Zone:Detailed" class to define my shading surfaces as part of hipped roof overhangs. What I need to do is simply to deploy the shade during summer and remove it during winter.

To test this, I considered 5 scenarios; a) No shading surface at all, b) fixed shade with no transmittance schedule, c) fixed shade with transmittance schedule = 1, d) fixed shade with transmittance schedule = 0 and e) shade with seasonal transmittance schedule (i.e. sch = 1 in winter and sch = 0 in summer). My analysis showed that cases (b) and (d) are exactly matching, cases (a) and (c) are slightly different (0.1% and 0.4% difference in heating and cooling respectively). When I apply case (e) the results are 1.5% higher in heating energy compared to case (a) and 3% lower in in cooling energy compared to case (d).

I realized that the reason could be due to the "DetailedSkyDiffuseModeling" algorithm option that is enforced when the transmittance schedule varies, and thus the results may not be comparable. However, I tried to use the "DetailedSkyDiffuseModeling" algorithm for cases (c) and (d) but that didn't change the results from what it is (i.e. using "SimpleSkyDiffuseModeling" algorithm). I also tried to use EMS to vary the transmittance schedule, I can see that the schedule values are changing (by reporting the new schedule) but for the results the program ends up using the base schedule assigned in the "Shading:Zone:Detailed" class.

I came across this relevant issue and this on GitHub and looked at the comments by @Archmage and @JasonGlazer. I am not sure if the issue is resolved? and is there any workaround? I am using energyplus v9.1!

Thank you!

### Shading control with variable transmittance schedule

Update I am updating this question since I did the test again using the latest version of EnergyPlus (V9.6).

I am investigating a simple concept on the impact of dynamic shading on buildings thermal loads using energyplus. I am using the "Shading:Zone:Detailed" Shading:Zone:Detailed class to define my shading surfaces as part of hipped roof overhangs. surfaces. What I need to do is simply to deploy the shade during summer and remove it during winter.

To test this, I considered 5 scenarios; scenarios:

• a) No shading surface at all,
• b) fixed shade with no transmittance schedule, schedule,
• c) fixed shade with transmittance schedule = 1, 1,
• d) fixed shade with transmittance schedule = 0 and 0,
• e) shade with seasonal transmittance schedule (i.e. sch = 1 in winter and sch = 0 in summer). summer).

My analysis showed that cases (b) and (d) (d), and cases (a) and (c) are exactly matching, cases (a) and (c) are slightly different (0.1% and 0.4% difference in heating and cooling respectively). matching. When I apply case (e) the results are 1.5% higher in heating energy compared to case (a) and 3% (c) and lower in in cooling energy compared to case (d). (d) (about 4% difference).

I realized that the reason could be due to the "DetailedSkyDiffuseModeling" algorithm option that is enforced when the transmittance schedule varies, and thus the results may not be comparable. However, I tried to use the considered "DetailedSkyDiffuseModeling" algorithm and "updating frequency = 1" for cases (c) and (d) but that didn't change the results from what it is (i.e. using "SimpleSkyDiffuseModeling" algorithm). all the cases.

I also tried to use EMS to vary the transmittance schedule, schedule (overriding a schedule), I can see that the schedule values are changing (by reporting the new schedule) but for the results the program ends ended up using the base orignal schedule assigned in the "Shading:Zone:Detailed" Shading:Zone:Detailed class.

I came across this relevant issue and this on GitHub and looked at the comments by @Archmage and @JasonGlazer. @JasonGlazer but I am not sure if the issue is already resolved? and if there is there any workaround? I am using energyplus v9.1!workaround!

Thank you!