They have deals with the power company for frequency regulation or some other high value service I would guess. That's why only certain electricity companies are allowed.
I bet the homeowner gets a reduction in their bill on the basis of total kWh per month, but Tesla is participating in the local energy market on an hour by hour basis, earning far more money in the afternoon "peak AC" hours.
I bet the homeowner gets a reduction in their bill on the basis of total kWh per month, but Tesla is participating in the local energy market on an hour by hour basis, earning far more money in the afternoon "peak AC" hours.