Carbon Intensity 
A Google Assistant Action to query your current local electricity carbon intensity.
View in the Google Assistant Directory.
Running locally
There's an odd limitation of the firebase-tools CLI that requires you to
export your configuration locally first. Otherwise you'll get some nice untyped
errors at runtime.
To do that first export your config:
firebase functions:config:get > functions/.runtimeconfig.json
Then run the local "emulator":
firebase serve --only functions
I like using ngrok to poke a tunnel into my NAT:
ngrok http 5000
Then point your Fulfilment link to your local endpoint which looks something like this: https://deadbeef.ngrok.io/carbon-intensity/us-central1/webhook
Deployment
cd functions
npm run deploy