Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
When loading an EPW file, OpenStudio checks the file to see if it is AMY or TMY. This check is performed by seeing if all of the dates listed are in order, that the presence or absence of a leap day is consistent with the actual year, and that the data in the header is consistent with the actual year. If the file passes these checks then it is assumed to be an AMY file and OpenStudio sets the simulation run period to that actual year, otherwise OpenStudio sets the run period to the start day of week option. Certain functions in OpenStudio (such as calibration) are only available when an actual year is specified. The user can override the simulation run period if they want to specify that a file represents a specific year, they can even do this to perform calibration using TMY data (which is probably a bad idea). Therefore, it is a pain that the year from the AMY file is not brought into OpenStudio automatically if there is inconsistent data in the header. However, the user can override this setting and provide the actual year.
As I understand it there is some work underway to clean up how dates are represented in EnergyPlus. It is my hope that effort will clarify which settings are important and which are not.
