Anybody here owns a Roadster? My company does and it has Open Vehicles Monitoring System, OVMS in it.
I can see were it is, control the charge, etc and it uses almost nothing. The Roadster has almost no vampire drain.
I don't see a reason why Model S should. Staying connected and sending some bytes to a app doesn't use 2,5kWh a day.
A iPhone could do the same inside Model S and only use 30Wh/day.
No, something inside Model S is not very efficient.
What's interesting, is the Tegra 3 in the center console unit was designed with a special low-power core designed just to handle background tasks that would seem ideally suited for what the car needs while asleep:
Tegra 3 5th Core
I wonder if it's some other subsystem that's responsible for the signficant power usage...