What amount of extra power is used by a Tesla’s Sentry Mode?
I was curious myself, so I measured my Tesla Model Y (Long Range), with SentryCam (Software 2021.4.12) on with my Sense whole house power monitor. Below is an expanded section of my power usage.
A time at night was selected when no other power usage in the home was changing to establish a baseline power usage without Tesla charging. This allows seeing just the additional amount of the Tesla charging by subtracting out the baseline.
The temperature at night was about 35F degrees. There was almost no traffic (certainly not within 30 feet of the car), and the nearby animals are mostly rabbits and squirrels, if that makes any difference to the usage.
SentryCam On Results
As can be seen on the power monitor results shown at the top, the average usage baseline for the home is about 1000 watts. The 2 orange peaks shown, which are the Tesla charging times, are about 8900 watts. Subtracting out the baseline yields about 7900 watts for the peaks. So the 1st peak is 9 minutes at 7900 watts and the second is 15 minutes at 7900 watts. The time spacing between the charging times was a consistent 6.5 hours over many days with Tesla sitting idle.
So the car is charging at approximately 7900 watts for a period of 9 to 15 minutes, or about 1185 to 1975 watt hours every 6.5 hours.
Using the larger one, the Tesla recharged 1975 watt hours. Averaging that out over 6.5 hours frequency means the standby power usage averages, at most, about 300 watts each hour. That means it uses about 0.4% of the 75 kwh Model Y Long Range per hour. If I left it at a parking facility at 70% charge and let it run to 20% charge, it would run for about 125 hours or 5 days
SentryCam Off Results
After running with SentryCam off overnight and outdoor night temperatures being the same, there was no charging of the car at all.
SentryCam is resulting in about an average 300 watts per hour usage (with a low end of 180), and the Tesla Model Y Long range (as of software version 2021.4.12 and in middle of March 2021), charges the car every 6.5 hours (probably due to some thresholds of charge replenish internal settings).
For an average US electric cost of $0.1319 per kWh as of February 2021, that means it would be costing $0.95 per day to run, or $346.63 per year when idle.
So depending upon where you live, and what kind of damage to your car you might experience, it may only be appropriate to turn on SentryCam where and when needed.