Setup guides → Tesla

Tesla

Sunplug talks to your car rather than your wallbox, which means there is nothing to install in the garage and nothing to configure on a charger. It sets the charging current amp by amp as the sun changes, and because it can read the battery it knows when to stop.

Which cars work

All of them. Model 3, Model Y, Model S and Model X, of any year Tesla's own API supports.

That includes pre-refresh Model S and Model X, which matters more than it sounds. Tesla changed how commands are sent partway through: newer cars require cryptographically signed commands sent over a different path, while older ones use the original REST endpoints. A tool that only implemented the new path silently stopped working for anyone with an older S or X, and several did exactly that.

Sunplug speaks both, and picks per car — so a household with one of each is fine. My own Model X is a 2020, which is rather how I came to notice.

Connecting

1. Settings → Equipment → Cars → Connect with Tesla
2. You are taken to Tesla's own sign-in page. Sunplug never sees your password.
3. Approve the permissions Tesla lists, and you are returned to the app.
4. Your cars appear on the dashboard within a few seconds.

You can withdraw access at any time from your Tesla account, without touching Sunplug.

What Sunplug asks for, and why

Location is the one worth a sentence. Sunplug uses it for a single question: is this car at your house? Without it, a car plugged in at work could be sent a charging command based on your roof. If you would rather not share it, leave the permission off and Sunplug assumes any plugged-in car is at home — which is right almost all of the time.

Setting your targets

Each car gets one slider with two handles. The blue stretch is the floor the grid guarantees overnight or during your set schedule; the amber stretch is how much further the sun is allowed to take it.

The car is always usable in the morning, sunshine does the rest, and it never charges past your solar target unless you ask. Boost charges now at full rate; Trip takes a departure time and a target, then works backwards and starts only as late as it needs to.

Two cars

Both charge at once, sharing whatever surplus there is, inside the combined limit your wiring allows. You can give one car priority or split evenly. AI-driven charging decisions are coming: with several cars, Sunplug will work out which one to charge first.

This is the thing ChargeHQ never did, and the reason Sunplug exists.

If you change the rate in the Tesla app

Sunplug notices. If it commands 16 A and the car reports something else for long enough, it concludes a human is driving and hands control back rather than fighting you over the same setting. The car card shows "control paused" and you resume it when you are ready.

When it does not work

"Something went wrong. Try again later"

If Tesla's own sign-in page shows this, the problem is at their end and not yours — nothing you can change in Sunplug will affect it. Tell me and I will check whether it is the known fault or something new.

Commands are accepted but nothing happens

Newer cars need a virtual key added before signed commands are honoured. If Sunplug reports success and the car does not change rate, this is usually why, and the app will prompt you to add it.

The car shows as "away"

Sunplug thinks it is not at home. Either it genuinely is not, or the location permission was granted and the home position needs correcting in Settings.

Charging stops and starts repeatedly

It should not — Sunplug waits several minutes before stopping and longer before restarting, precisely to avoid this. If it happens, the wait times in Settings have been turned down too far. Every cycle wears a physical contactor, so the defaults are deliberately patient.

Not a Tesla? Everything here except the state of charge works through your wallbox instead, whatever you drive.