- powerwall owners can now set a state-of-charge threshold to determine when a tesla is charged during blackouts.
- the powerwall update also will adjust the amount of energy shared with the tesla based on demand from the house.
- it only works with the model 3 and model y in north america right now; model s and x are coming soon.
tesla’s powerwall, essentially a giant battery plugged into the wall, gives homeowners the ability to store power produced either by solar panels or during off-peak times to be later used to power their home or charge their evs. a new change to the setup addresses concerns that, during an outage, it could potentially suck all available power while a car is charging, leaving the house itself high and dry. an update to powerwall has been pushed to make it a bit smarter.
if you’re a tesla and powerwall owner, the tesla app can be used to set the threshold of power being transferred from the powerwall to the vehicle in different scenarios. if everything is fine with the grid, the vehicle charges as it normally would. but if the power is out, the powerwall adjusts its output.
for example, if there is a blackout and demand from the house is low, the vehicle will be charged with surplus power while maintaining the amount of electricity, keeping the house going. if the demand from the house is high, the tesla’s charge rate is lowered to prioritize the home even more.
if at any time the state of charge of the powerwall falls below the owner's set threshold during a blackout, the powerwall will completely stop charging the vehicle. so if you use the app to set the threshold to 80 percent, the powerwall will only charge your tesla until the powerwall's state of charge hits 79 percent.
updates to both the tesla and the powerwall were needed to make this a reality. the system currently works with north american model 3 and model y vehicles. tesla says updates for models s and x, and vehicles in other regions, are coming soon.
the update is particularly important for folks living in california. fire season is coming up and with it, the state again expects to be subjected to rolling blackouts to keep power lines from sparking fires. during those blackouts, with this update, a house could be prioritized over a vehicle, especially if stay-at-home orders related to the coronavirus pandemic are still in place.