Powerwall integration should have energy and capacity sensors

The Powerwall integration currently exposes the battery charge % as a sensor however the Powerwall API also returns the battery charge energy in watts and also capacity in watts.

The tesla_powerwall Python library has two methods that returns these values

#=> 14807 (W)
#=> 28078 (W)

I think it might be useful to have these values returned as a sensor too.

The capacity is an interesting metric to monitor and compare over time for battery degradation.

Don’t forget to vote for your own request.

Can I also suggest temperature as a useful sensor. In the winter when the Powerwall is cold it charges slower so it’s useful to be able to monitor this.

If this is implemented, please use the correct units.

The energy and capacity are measured in ‘watt hours’ (Wh), not watts. The GitHub doc’s need correcting.
See https://www4.enphase.com/en-in/support/what-difference-between-watt-and-watt-hour

The Powerwall when new comes with 13,500 Wh, or 13.5 kWh of usable capacity.
From https://www.tesla.com/powerwall: “Energy Capacity 13.5 kWh”

I believe the 10 year warranty states that after 10 years, it should still have at least 70% of that capacity. So I second this RFE as a graph over the years will help to show if the Powerwall is staying within warranty or needs service from the supplier.

As someone with a failed powerwall this data would really help with the Tesla warranty process.
There were arguments over its capacity. Would be nice to have the history to show them.

System Status provides information on batteries and inverters. (nominal_full_pack_energy is useful for monitoring degradation over time

  "command_source": "Schedule",
  "battery_target_power": 15000,
  "battery_target_reactive_power": 0,
  "nominal_full_pack_energy": 42122,
  "nominal_energy_remaining": 34801,
  "max_power_energy_remaining": 0,
  "max_power_energy_to_be_charged": 0,
  "max_charge_power": 15000,
  "max_discharge_power": 15000,
  "max_apparent_power": 15000,