Beginner: nod-red-contrib-tibber-api : where can i find HOME ID?

Trying to run my first flow, getting Tibber energydata using https://flows.nodered.org/node/node-red-contrib-tibber-api

copied from above site : Tibber Feed node (tibber-feed)

tibber-feed

Realtime power consuption data from Tibber Pulse. Provide API token, Home ID and select what kind of information you want to retrieve.

I have entered my Tibber API code (I have) but cannot figure out where to find the HOME ID code?

All help is welcome!