Heating a swimming pool

[Azelphur]

Hi folks,

I've recently got a new solar system installed with 53kWh battery. I've got predbat up and running and the basics are up and running. predbat is already doing the thing and saving me money, yay.

The biggest power consumer in my home by far is the heat pump for the swimming pool. It'll quite happily chew through 40kwh in a day. But of course the fun part is that it doesn't matter when it runs. The pool looses about 1°C per day, and I'm quite happy for pool temp to be in a reasonable range of temperatures (could even "store" energy in the pool).

My question is what's the best way of making predbat aware of this? I currently have:

  export_triggers:
    - name: 'pool'
      minutes: 30
      energy: 1.5

Because the heat pump will typically use about 1.5kwh of energy in 30 minutes, it obviously wants a lot more than that in a day (should I be scaling that up to eg energy 6 minutes 120?). This seems to work, but I'm not convinced it's financially optimal, it'll run the pool heater on excess solar (which is worth 12p/kwh) when it could run it on grid later for 3p/kwh).

I looked into iBoost but wasn't initially convinced since it doesn't let me set a target temperature, but feel free to tell me I'm wrong there.

The only other thing of note is there's a bit of counterintuitive here, usually you'd run a heat pump 24/7 and let it maintain temperature. The reason I am not doing that is because running the heat pump also requires running the water pump, which is 500w constant load. So ideally we want to run the water pump (and thus the heat pump too) for as short a time as possible.