Tesla officially launches Charge On Solar

July 29, 2023

BHASD July 29, 2023

Charge on Solar

With Charge on Solar, your Tesla vehicle can charge using only excess solar energy produced by your Tesla solar system. Using excess energy to charge your electric vehicle maximizes the value of your home’s solar system. Use the Tesla app to set Charge on Solar limits and have your vehicle charge using extra solar energy.
To use this feature, you need the following hardware and software at a minimum:

Hardware	Software
Model S, Model 3, Model X or Model Y	2023.26 or Higher
Powerwall with solar on site	23.12.10 or Higher
Tesla app	4.22.5 or Higher

Note: 2012-2020 Model S and 2015-2020 Model X are not eligible for this feature.

Setting Up Charge on Solar in the Tesla App To set up Charge on Solar in the Tesla app, follow these steps:

Open the Tesla app.
Select your vehicle.
Tap ‘Charge on Solar.’

Follow the prompts to set your charge limit and a charge location.

Every time you charge at your configured location, Charge on Solar will automatically charge your vehicle to your set charge limit using only extra solar energy.

Charge Limits

In the Tesla app, Charge on Solar has a sun slider that lets your vehicle charge from any energy source, so you have confidence your vehicle has the range you need for your daily driving needs, even if there isn’t enough excess solar to charge your vehicle. This slider appears to the left of your usual charge limit slider you’re already familiar with.

Charge on Solar sun slider in the Tesla app

You can adjust your charge limits in the Tesla app or from the vehicle touchscreen when your vehicle is at your Charge on Solar charging location. Follow these steps while your vehicle is plugged in:

Open the Tesla app.
Select your vehicle.
Drag the left slider with a sun icon left or right. Your vehicle will charge to this level from solar and the grid.
Drag the right slider left or right. Your vehicle will charge on excess solar to this charge limit.

Your vehicle will charge from solar and the grid when your current charge level is below the left sun slider. After your vehicle's charge level passes the sun slider, your vehicle automatically switches to only charge on excess solar up to your charge limit. Solar power and home loads are variables so if you ever want to charge faster, you can simply increase the lower charge limit to a desired range. To maximize solar charging and have enough range, plug in your vehicle during daytime whenever you’re at home. Set the Charge on Solar sun slider at a level that ensures you always have enough range for daily driving if there is not enough excess solar to charge your vehicle above this limit.

Typical Operation

The scenario below shows typical Charge on Solar behavior when a Tesla vehicle is plugged in at a home with Powerwall. Notice that the vehicle will adjust charge power approximately every 10 seconds to match the excess solar power and power consumption elsewhere in your home. Note: Your vehicle may delay the start of charging until there is at least 1.2kW of stable excess solar to maximize efficiency and lifetime of your charging equipment.

Tesla app vehicle and Tesla Home screens with Charge on Solar

Using Scheduled Charging with Charge on Solar

Scheduled Charging allows you to charge your vehicle’s battery with excess solar only until a specific time. Once your selected time arrives, your vehicle will accept charging from any source up to your lower charging limit. If you have a time-of-use rate plan, you may benefit from using both Charge on Solar and Scheduled Charging since your Tesla vehicle will charge from excess solar during the day and, also, charge from the grid at night when energy costs are low. To schedule charging in the Tesla app, follow these steps:

Open the Tesla app.
Select your vehicle.
Select ‘Schedule.’
Enable ‘Schedule’ and select a time.

Using Powerwall Modes with Charge on Solar

The following Powerwall modes work seamlessly with Charge on Solar:

Storm Watch
Powerwall will prioritize charging from any source to prepare for an outage during severe weather events before allocating any excess solar power for vehicle charging.
Backup Reserve
If your Powerwall’s stored energy is below the Backup Reserve, your Powerwall will prioritize charging to the set Backup Reserve percentage before allocating any excess solar power for vehicle charging.
Self-Powered
With Self-Powered, Powerwall will allow your Tesla vehicle to charge on excess solar until the set charge limit while covering changes in home loads and solar production until the vehicle adjusts its charging power. Once the vehicle has met its charging limit, your Powerwall will charge on excess solar as usual. This is the recommended mode to maximize Charge on Solar operation with your vehicle.
Time-Based Control
With Time-Based Control, Powerwall stores energy when energy costs are low and may sell that low-cost energy back to the grid when energy costs are higher instead of using the excess solar energy for Charge on Solar. You may also see this behavior during Virtual Power Plant or Utility Program events. In most cases, you will see the vehicle pause charging during Peak to prioritize total savings or charge your Powerwall from excess solar while charging your vehicle during Off-Peak from the grid.
Go Off-Grid
When Powerwall is off-grid, your Tesla vehicle will continue to charge on excess solar unless Powerwall prioritizes saving energy for home use during the outage.