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.
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.
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
I saw a post by chris and got work reconstructing my DDY file with the ASHRAE clearsky model which is sufficient for my needs. I also realized that using the LB EPW to DDY the results are just 2 design days (winter and summer, the DDY had multiple months of design days) and also with clearsky. With this, the results are very similar between the HB to OSM and Peak Loads!
Maybe try to unify the sky model using chris’s post that I mentioned along my screenshot.
Hi, @adrisonet
Many thanks for your reply and suggestion.
I’ve tried your recommendation to re-create the ddy file, but the problem I had is the openstudio module delete the sky properties data when running the design day sizing (Peak load component doesn’t have this issue, it works well).
Therefore, even I reconstructed the ddy file as your way, the sky properties will be ignored by openstudio component.