I did something like this. I buy my electricity at wholesale prices, and the supplier has an API with price predictions, so I used node-red to compare insolation forecasts, and price forecasts to work out what time-blocks to run the pool pump (when solar high, or price low, or cheapest forecast times to achieve a minimum number of hours per day).

Not quite the same as home automation, but there's a home-made renewable energy system community too:

https://lemmy.world/c/hmres

!hmres@lemmy.world

Home Made Renewable Energy Systems

I gotta say... Your documentation is really good. You definitely have more experience with node red than myself so I am not sure how one would improve upon your work so far. Plus most of my improvements would probably be a little advanced for the aim of your project as I tend to go down a rabbit hole whenever I automate something lol.

Mostly, my two cents are for if you want to go further towards a smart pump and getting more data into home assistant:

• Look for a way to track the flow of water through the pump to watch for signs of blockage or pump failure.
• Look at what options would you have for water quality sampling/intervention (if you do any maintenance for that).