I thought I would share my latest gadget
It takes energy that would otherwise be exported to the grid and diverts it to the Hot Water Cylinder (HWC).
It is only applicable for a grid tied solar system (with or without batteries) and requires a separate CT clamp meter to measure the amount of exported energy.
The reason we want to do this is due to the disparity between the cost of importing energy vs price of exported energy. In my case it costs approximately 3 times as much money to import energy from the grid than I make exporting. So best use it locally.
With the export sensor information, a HA automation controls how much energy to put into the HWC.
The device contains a relay to turn on/off diversion mode and controls an SCR to adjust the amount of power.
Warning. This project deals with high voltage, high current please do not attempt to replicate this unless you know what you are doing.
Here is a link to my repository for more details Export Diversion Controller
