Our electricity demand is billed in kVA, not kW. I know that kW demand would be tagged as "total ac elec demand sensor point".

How is everyone tagging apparent demand? "total apparent ac elec demand sensor point"?

This seems incorrect because elec-demand is a sub-type of active-power.

We are also measuring instantaneous apparent power, which would be tagged as "total apparent ac elec power sensor point", and I want to differentiate between the two.

Thoughts?

Hi Will,

Thanks for the feedback.

How is everyone tagging apparent demand? "total apparent ac elec demand sensor point"?

Looks close to me. I would suggest adding the elec tag and a tag that indicates the direction of electricity flow (i.e., net, import, or export). Also, the point entity should have a tag for hisMode with a consumption value.

This seems incorrect because elec-demand is a sub-type of active-power.

I can see why this might be confusing. Please note we might also need to add support for electric current demand to Project Haystack which can make this concept even more confusing. We will look into improving the relevant documentation.

For now please note instantaneous electric power sensor measurements should have a hisMode tag with a sampled value.

FYI, recently we defined a Xeto spec ElecTotalImportAcApparentDemandSensor that describes a sensor for total AC electric apparent demand imported.

Also, we defined a Xeto spec ElecTotalImportAcApparentPowerSensor that describes the sensor for total AC electric apparent power imported.

These Xeto specs are under development and subject to change, however, we expect these initiatives will improve how we model these systems.

Stay tuned for more updates on this.

-Rick

Hi, I would like to add to this conversation.

Utilities track KW, KVA (apparent power), and KVAr (reactive power). The beer analogy is as follows: Your beer glass is 16 ounces (KW), 12 ounces is liquid beer (apparent) and 4 ounces is beer foam (reactive). You are billed for the foam, but it really does no work.

Important to this conversation is most modern meters (and utilities) track all three. And in some cases, charge for carrying reactive loads, so tracking this in your tagged data is essential to capturing current and future costs.

-Mark

Hi Mark, thanks for sharing!

FYI, Project Haystack defines how to model active, reactive, and apparent power demand.