PH recommends using siteID for each individual building even on a campus. It would be useful to have a location or campus ID so that weatherRef, tz, utility, etc do not need to be separately accommodated for lookups.

We are working on an energy digital dashboard for a small Net Zero Energy mixed use project and using NREL's energy data bus for our time series data. We are organizing each building (siteID) into siteGroups - entire campus, commercial (all commercial), retail, commercial kitchen, commercial office - so that we can show energy intensity for each group. Perhaps we can add a tag that indicates that a specific site group is a masterSite so that certain values are shared across siteIDs.

Any thoughts on grouping siteIDs to designate a geographically contiguous campus?

PH recommends using siteID for e

Just to be pedantic, its actually the siteRef tag

Any thoughts on grouping siteIDs to designate a geographically contiguous campus?

You can create whatever entities you need and organize them with refs. There is no standardized tags for organizing sites, but I think most people use region or campus.

For example:

id: @Va-Tech
campus

id: @Lee-Hall
site
campusRef: @Va-Tech