Tesla’s ‘Charge on Solar’ lets Powerwall owners send excess energy to their EV

Tesla has launched a feature called “Charge on Solar” that allows owners to fill up their electric vehicles’ batteries using only excess solar energy. As TechCrunch notes, the automaker started testing the capability in May, but now it’s more widely available to Tesla customers in the US and in Canada. The number of people who can access the feature, however, likely remains pretty limited. To start with, it will only be accessible to those who have newer Teslas — 2021 and later — who also have a Powerwall. That’s the company’s battery system that stores solar energy harnessed by solar panels. 

To enable Charge on Solar, users will need to fire up their Tesla app, choose the feature and then set it up. They’ll then see a slider with a sun icon within the feature’s settings that they can drag left or right to set the charge limit. The vehicle will charge itself from solar and the grid like usual before it reaches the sun slider, ensuring users have enough power to get where they need to. But after reaching the sun slider, the vehicle will only charge itself using excess solar energy. 

The Powerwall will still prioritize storing backup energy or charging other appliances when it’s in Storm Watch mode before allocating any excess solar power for vehicle charging. Charge on Solar will truly only charge EVs using excess energy, which is also why owners worried about not having enough juice can set a time limit for it. Of course, they can also adjust their charge limit, or switch off Charge on Solar entirely if they want to be absolutely sure that their batteries will get fully charged.