Linky smart meter electricity consumption logger

This program requests electricity consumption data from a Linky smart meter and stores it in a Postgres database.

That makes it easy to visualise the data in Grafana.

This was my initial implementation, and it is useful for backfilling old data, but the one I run daily can be found at: https://cgit.twilken.net/dotfiles/tree/tw/services/personal-data-exporter.scm#n50