It seems like this gets tangentially mentioned places but not really addressed much.
I have a bunch of loads - say lighting loads or HVAC loads - and I would like to see what the sum of those loads is on my energy dashboard. It’s not actionable data, so it doesn’t really need its own sensor (and if you build a template sensor, it means you don’t get any of the data prior to setting up the template sensor), but it is useful to know. I also can’t use a template sensor really because the various individual devices have different upstream devices so they can’t be combined using the existing “upstream device” modality.
In my case, I would like to see my HVAC loads both grouped (IE, another “individual devices” table with just those loads broken out) and summed (IE, total HVAC consumption). This would be really helpful because it would allow some visibility into the various tradeoffs between pieces of equipment that effect the same rooms in the house (IE, cool with device A might be more cost effective than cool with device B, or maybe AC-to-dehumidify is more or less effective than the dehumidifier or AC+dehumidifier).