Ideas for electricity price based heating automation

Hi! I have a Thermia geothermal heat pump that powers the whole-house underfloor water heating. In Home Assistant I have an hourly price for electricity:
Screenshot 2022-02-06 at 12.36.48
and the following controls for the pump via ThermIQ-MQTT:

Here are the following automations I’m either running or planning to implement:

  • When 3kw or 6kw heaters turn on
    • turn off the heaters if the electricity price is too high (I’ll have to figure out how not to create favourable conditions for legionella)
  • during summertime, the compressor turns on approximately once per day, so I am planning to schedule this run for a time when the electricity price is cheapest
  • when I have a calendar event such as “Vacation” or “Visiting wife’s parents” that lasts for more than 2 days, then I plan on turning the pump off ahead of the event (e.g. 1 day before) and turning the pump back again based on the actual and desired room temperature difference and the time when we’ll be back

I probably forgot something, but feel free to suggest your ideas. Also, feel free to point out the parameters that I could play with that I’m probably not aware of right now. I’m mostly setting the indoor target temperature and hotwater start and stop temperatures. And also turning the pump on and off. I’m not messing with the curve.

I have thermostats installed in all rooms, but the thermostat system is only turning off and on different parts of the floor heating based on the temperature. It cannot directly call for heat from the heat pump. I could do that, but I haven’t seen the need, as setting the general indoor temperature, plus, adjusting certain rooms to cool down for the night is usually enough.

I plan on measuring price differences compared to not running any automations to figure out whether it’s worth it. I have quite a well-insulated house and floor heating has huge thermal inertia, so short-term changes are not likely to affect the bill that much. I’m not expecting huge gains, but it’s still nice to do all of this and know that it at least saves money rather than increases our utility bills.

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Thanks for sharing. I just bought Husdata H60 for my thermia diplomat G3.

Maybe this give u inspiration?

Thanks! I’ll take a look.