Peak load results difference between "HB Peak Loads" and Openstudio

[gogog]

Dear community!

I am trying to get the peak cooling and heating load of building, but not sure how to calculate it since there is a huge difference in the result from “HB Peak Loads” component and Openstudio.

1. As below capture shows, total peak cooling from “Peak loads” is much higher than the one from openstudio zsz. I’ve checked the results, and peak load of each room also has huge difference.
   

   

2. The peak of sum from “cool_bal” also not same with peak cooling results.
   

   

3. For heating, the result from “Peak Loads” and openstudio is similar, but the peak heating results is different with the sum of “heat_bal” data.
   

   

Attached the grasshopper script I’ve tested.
It would be very helpful if you can provide some comment on it.
Thanks!

testmodel.gh (121.1 KB)

[gogog]

seems there is no solar gain results for sizing calculation.
May I know why it doesn’t count solar load?

[gogog]

Seems the peak load difference between “HB Peak Loads” and Openstudio is because of solar gain load.
As below graph shows, it is unable to get the solar load for sizing day, but the annual energy balance has solar gain.
And the peak loads from openstudio is very similar with the one from “HB Peak Loads” without solar gain load

May I know if it is some bug with openstudio? or I didn’t setup the HB script properly?

[gogog]

I think I found the issue with “HB Model to OSM” component. Sky properties input from ddy file will be missed when this component write the idf file.

If I change the idf file same with “HB Peak Loads” and run again, it will get the solar gain results for summer sizing day.

So, the question is, how I can keep these two input from ddy for openstudio sizing?
@chris May I know if you any idea on this issue? many thanks!