It’s nice living in de Netherlands, you can read your energy meter with DSMR indeed (and get all the data including solar delivered back to the network etc). Or you buy this thingy [0], plug it in and boom all data flows into Home Assistant’s very excellent energy dashboard.
I own one as well and actually flashed it with my DSMR library combined with nerves. Another way is to let the slimmelezer-plus expose a TCP server and let Elixir’s genserver just parse the incoming telegrams through this package (see the livebook examples)
There are some other countries using this format as well. I know at least Belgium, Luxembourg, Ireland, Spain, Germany, Denmark, Sweden, Finland, and Hungary, though compatibility can vary.