Divert Excess Power - Control Relay

I’m still using a manual timer clock to divert solar power to my hot water. Obviously there are times when solar production is low and I’m using power from the grid.

What are other people doing?

My new heat pump hot water system will have its own timer. I will program it to only allow heating during the middle of the day (11am to 3pm) which corresponds to our Time Of Use off-peak (cheaper) tariff. If the sun is shining during this time & the hot water is below the heating set-point then the water will be heated along with power to other behind-the-meter devices, otherwise the excess power is exported to the grid.