Hello, I have came here to gather any ideas you have to help saving cost for electricity on heating of my mother’s house. We have spot eletricity instead of fix price ie there is different price every hour.
Background:
- Heating is done via 12kW electric boiler that has Shelly (wifi) relay in it for turning the boiler on/off
- Standard wall radiators are used without any smart valves
- House have solar plant with 10kWh battery. When heating is on, battery consumption is forbiden as heating would depleted it in few hours.
- Mom has spot electricity and the prices are available in Home Asisstant
Current status of heating
- HA switches electric boiler ON
-
Only on 11 cheapest hours of current day (Line Hranice vytapeni on graphs shows where the heating will be ON)
-
Only if any room temperature is under the target temperature
-
Some thoughs I am having
… And I cannot come to answer
- Would we save if we would be ignoring the spot price and just heat all over the day?
- Would we save if we would wait for the lowest electricity price of certain part of a day (night/day) and start heating from that point (black crosses on example)? In other words wait for the lowest point of each wave and start heating from this point?
This idea is based on fact that the start of the heating after long period of heating off is most power demanding (12kW). After water is warmer in the system, boiler eats less as you can see below.
