I forgot the WAF factor.
Since there were no cables, I thought I'm on the safe side. This is not the case.
I have to admit that I did not check first with my wife, but started enthusiastically to program in node-red and with the dashboard. I got totally lost connecting blocks with wires and watching the messages moving through the flows. But this project is connected with the real world, with people, a car, the weather, etc.
Instead of thinking in node-red flows and dashboard buttons, I need to think in use cases.
The basic use case is this:
- we come home with our car and plug it in
- we have something in mind about when we will need the car again and what charge level it should have to feel safe
- we want this to be cost optimised and we want a direct feedback about what this means
We solved this in the pre-node-red-aera by looking at the sky, checking the Tesla screen on how long the car thinks it needs to charge, and then decide, if we plug it in or not and wait for the sun to come out.
To solve the above use case with node-red (and without a mobile phone (WAF!)) I need a hardware box with buttons and screen near the charging plug. Luckily I have an ESP32 with OLED in my toy box, and ordered a rotary encoder with push button. I plan to use this as the control device, instead of a node-red dashboard.
The default for this box is to be disabled, which means the charge control is manual as before.
If the box is enabled, then it will show the estimated charging times for the three cases: charge with solar power only, charge with solar power and at low tarif times, charge immediately. Then with the rotary encoder you choose the charging strategy.
The box will basically replace the dashboard.
This will take some time, stay tuned.