Tesla Powerwall update makes it smarter during a power outage
For those charging Tesla cars at home, the Powerwall will work with the charging system to prioritize needs.

A smarter battery.
Tesla's Powerwall backup battery system for home use just got smarter. In an update released Friday, the Powerwall can now work with Tesla charging stations at home to prioritize energy needs during a power outage.
Before the update, in the event of a blackout, the Powerwall kicked in to supply power to the home and continue to serve juice to a Tesla charger if the car was plugged in. Now, the Powerwall will communicate with the Tesla charger and the two will work together to share energy.
If the Powerwall doesn't have enough energy stored to power the home's essential needs, such as air conditioning, it will automatically stop charging the car. Even if the home begins to show an uptick in energy needs, the Powerwall will slow the amount of juice headed to a Tesla before cutting it off entirely.
One of Tesla's at-home battery devices stores 13.5 kilowatt hours worth of energy, which isn't a whole lot when it comes to powering a home and charging an EV. Of course, you can buy multiple Powerwalls to boost the amount of energy storage. Without solar power, these devices charge from the grid, so hopefully there's enough juice before the grid goes down for some owners. It's more of a helpful tool for those with solar power at home.