SDK support of deprecated EnergyPlus output variables

Issue overview

The OpenStudio SDK (as well as the Application) supports deprecated output variables, i.e. no longer supported by EnergyPlus. Examples include:

• "Zone Windows Total Transmitted Solar Radiation Rate"
• "Zone Windows Total Transmitted Solar Radiation Energy"
• "Lights Radiant Heat Gain" (see Side Note below)

Both "Zone Windows Total Transmitted Solar Radiation" variables are supported up to EnergyPlus 24.1. With release 24.2, these have been renamed as:

• “Enclosure Windows Total Transmitted Solar Radiation Rate”
• “Enclosure Windows Total Transmitted Solar Radiation Energy”

I don't find SDK source code entries for the "Enclosure" variants.

Current Behavior

SDK source code files currently reference these variables (see here, here, here & here).

Regardless how (e.g. via the Application), an SDK-generated run/in.idf file could hold something like e.g.:

Output:Variable,
  *,
  Zone Windows Total Transmitted Solar Radiation Rate,
  Timestep;

This is now caught and reported in the generated run/eplusout.err file:

Warning ** The following Report Variables were requested but not generated -- check.rdd file
     ~~~   ** Either the IDF did not contain these elements, the variable name is misspelled,
     ~~~   ** or the requested variable is an advanced output which requires
                   Output : Diagnostics, DisplayAdvancedReportVariables;
                   ...
                   Key=*, VarName=ZONE WINDOWS TOTAL TRANSMITTED SOLAR RADIATION RATE, Frequency=TimeStep

This now creates unnecessary confusion for users, notably newcomers. Maybe best not to support deprecated output variables in OpenStudio. Maybe I'm missing something obvious - unsure ...

Expected Behavior

SDK source code files should no longer include/support deprecated EnergyPlus output variables. The OpenStudio Application should no longer offer these as options.

Steps to Reproduce

See Context below.

Possible Solution

Prior to upcoming SDK releases, (automatically?) track EnergyPlus changes in available output variables (e.g. here). Adapt SDK source code accordingly.

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Side Note

Raised a similar EnergyPlus documentation issue on “Lights Radiant Heat Gain”. My understanding is that this output variable hasn’t been available in EnergyPlus for more than a decade, yet continues to be listed in the IO Reference (even in 25.1). I think this is strictly a documentation fix on the EnergyPlus side. Nonetheless, OpenStudio (both SDK & App) still support a request for this deprecated variable (e.g. 3.6.1, 3.9.0). Just as with “Zone Windows Total Transmitted Solar Radiation” (“Rate” or “Energy”), probably better not to support deprecated output variables in OpenStudio.

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Context

Looking into reported output variable issues in this UMH post, I ran a small side experiment using the OpenStudio Application (1.6.0 & 1.9.0), requesting all (557) possible output variables for a variant of the US DOE Prototype SmallOffice (see here), and enabled the following (just in case):

OS:Output:Diagnostics,
  {fd2b9480-2f48-497a-96c6-b7ed055c5b05}, !- Handle
  DisplayAdvancedReportVariables;         !- Key 1

As expected, around 200 requested output variables weren’t generated by EnergyPlus (as reported in the run/eplusout.err file). This is expected for the vast majority of reported failures: for instance, any requested variables on fuels (e.g. diesel) or fluids (e.g. steam) will fail if these are not present in the model (fair enough). Yet a few failures seemed odd to me, including the ones listed above. I have not pursued this any further (i.e. on other failed variables). I can’t locate an SDK source file or online protocol that is intended to track deleted (or added) EnergyPlus output variables, similar to EnergyPlus. May be necessary at some point.

Start by reviewing the referenced output-variable entries in src/model/OutputTableMonthly.cpp, src/model/ThermalZone.cpp, and src/model/Lights.cpp, then compare them with the EnergyPlus 24.1-to-24.2 transition list. Check how the SDK and Application expose these requests, and verify that deprecated variables are no longer generated or offered while the Enclosure variants are handled where appropriate.