It sounds very strange...
I could easily reproduce this in OpenStudio by starting a new file (I have used version OS App 1.7.0 and SDK 3.7.0), drawing a simple box model (one thermal zone), applying the default ASHRAE office space type, construction set, and schedule set (including heating and cooling setpoints), activating ideal loads in the thermal zones tab, and without applying any measure (not even the default reporting measure), launch a whole-year simulation with a 6-timestep configuration.
The following code lines always appear at the end of the IDF file generated in run folder, corresponding to Output:Meter objects not configured by the user (and not present in the original OSM file):
Output:Meter:MeterFileOnly,
NaturalGas:Facility, !- Key Name
Daily; !- Reporting Frequency
Output:Meter:MeterFileOnly,
Electricity:Facility, !- Key Name
Timestep; !- Reporting Frequency
Output:Meter:MeterFileOnly,
Electricity:Facility, !- Key Name
Daily; !- Reporting Frequency
Output:Meter,
Electricity:Facility, !- Key Name
Timestep; !- Reporting Frequency
Output:Meter,
NaturalGas:Facility, !- Key Name
Timestep; !- Reporting Frequency
Output:Meter,
DistrictCooling:Facility, !- Key Name
Timestep; !- Reporting Frequency
Output:Meter,
DistrictHeating:Facility, !- Key Name
Timestep; !- Reporting Frequency
Even more, if I model a DHW system, Air-loop based HVAC system, etc., you can get a lot more Output:Meters, always in timestep reporting frequency.
In this simple box model I get the output in sql and eso files for only the Output:Meter objects corresponding to DistrictCooling:Facility and Electricity:Facility, as DistrictHeating:Facility is not supported in the last versions of EnergyPlus (now it's called DistrictHeatingWater:Facility).
Any idea on how to avoid this?
UPDATE: I could reproduce it identically also with OpenStudio App 1.5.0 (SDK 3.5.1).
By timestep frequency are you referring to the zone timestep or the system (HVAC) timestep? Zone timestep can be modified by the user in the Number of Timesteps per Hour input field, but the system timestep cannot.
https://bigladdersoftware.com/epx/doc...