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.

There is a device called solic that diverts excess solar to hot water heater

I can’t see why an iotawatt couldn’t control a hot water relay, even allowing for a manual override.

@overeasy - what do you think?

I think something like that should have its own controls, and the IoTaWatt would only be used (as is) to validate whether it is working properly and to measure any savings.

Hmm, or the other way round - something could use iotawatt data to work out when to turn relay on and off.

My understanding of those devices is that they vary the power into a resistive load, typically with a triac. So the control logic needs to be quantitative rather than qualitative. With their own control, they can regulate at very fine granularity, even per cycle, whereas using data from something like IoTaWatt would be coarser.

That said, my understanding of the OPENevse EV charger is that it responds to surplus energy data from an MQTT broker to adjust charge levels to a surplus energy metric.

The line starts to be fuzzy between what is an energy monitor and what is an energy manager. It’s all academic as far as IoTaWatt is concerned. I don’t have enough time to finish the energy monitor functionality, much less start on management functions.

The good news is that it’s all open, so anyone so inclined can add their own process to the firmware to do whatever strikes their fancy.

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