The installation of my fuel cell heating required a bi-directional power meter. Bonn Netz, my local power network provider, uses meters of type EasyMeter Q3M which have two infrared interfaces: A bidirectional D0 interface, and a read-only info interface. I use the info interface (INFO-DSS) to read out power consumption and production of the three phases. For this, I built an optical interface, a 3D printed housing for it, and use the UART of a Raspberry Pi with python to get the values.
I want to integrate my new Viessmann Vitovalor 300-P fuel cell heating into my home automation. For this, I use the Optolink interface, vcontrold from the openv community, and create my own configuration files from several sources.