This Price Light manual covers everything a SaveElectro Shelly plug can do: the colours, brightness and night dimming, and the optional Power when cheap mode with its one-touch boost, stop-when-full and safety off without internet.
For a Shelly Plus Plug S, Plug S Gen3, Plug PM Gen3 or Plus Plug UK running the SaveElectro plug script from My price lights.
The Price Light is an ordinary Shelly smart plug with a small SaveElectro script on it. The plug's light shows the electricity price right now as a colour: green when it is cheap, yellow when it is normal, red when it is expensive. You see the price at a glance from across the room, without opening an app.
You choose per plug in SaveElectro what its socket does — three choices — and Boost gives power right now:
The plug only shows the price colour; its socket is off. This is how every Price Light starts.
A normal socket that also shows the price colour: the power stays on, and the plug's button switches it on and off as usual.
The socket gives power only while electricity is cheap (green or lime light). Plug in a battery charger and it charges when electricity is cheap, by itself.
In Light only and Power when cheap, press the plug's button or Boost 1 h on My price lights: power for 1 hour at any price (+1 hour on the phone if needed). Press again during a boost to end it early — the plug goes back to what you chose.
http://192.168.33.1 in the browser.192.168.1.57.Keep the script private: it contains your key. If you think it has been shared, press New key in SaveElectro and paste the new script into the plug.
The colour follows the spot price including VAT for the current quarter-hour, the same price levels you see everywhere in SaveElectro, so the plug, the website and your alerts always agree. The plug checks the price every quarter-hour.
| Light | Spot price incl. VAT (standard) | Meaning |
|---|---|---|
| Purple | below 0 c/kWh | Negative price |
| Cyan | 0 c/kWh | Free |
| Green | up to 3.8 c/kWh | Very cheap |
| Lime | up to 6.3 c/kWh | Cheap |
| Yellow | up to 10 c/kWh | Normal |
| Orange | up to 18.8 c/kWh | Expensive |
| Red | above 18.8 c/kWh | Very expensive |
| White | — | No internet or no fresh price: the plug can't reach SaveElectro. It turns white within about two minutes and never keeps showing an old "green". Without Wi-Fi, and while reconnecting, Shelly's own red or blue signals may show instead. |
Your own colour limits (Premium): if you set your own price colours in Settings → Price colours, the plug follows them too, within a quarter-hour.
Choose Bright, Medium or Low for each price light in SaveElectro. With Power when cheap on, the light is a bit dimmer while the plug's power is off, so you can tell whether it is switched on.
Tick Dim at night and the light goes to Low during your quiet hours: 22:00–07:00 on the free plan, or your own quiet hours on Premium. "🌙 dimmed now" in SaveElectro shows when it is in night mode.
Changes reach the plug with its next price check, within a quarter-hour. Nothing needs to be changed on the plug itself.
In this mode the plug's own switch follows the price: power on while electricity is cheap — the light is green or lime, or cyan (free) or purple (below zero) — and power off at yellow, orange and red. On Premium you can also allow yellow (normal price) for an appliance that should run more often: choose “Cheap or normal” under Power on when on My price lights.
Press 💡 Light only — power off to switch the socket off (the light keeps showing the price), or 🔌 Always on for a normal socket.
In Power when cheap mode, the plug's button always wins for one hour:
The button works on the plug itself, so it works without internet too. SaveElectro shows "Boost until 22:45" or "Off until 22:45" once the plug has reported it.
In Light only — power off the button works the same way: press = power for 1 hour, press again = off sooner. In Always on it is the plug's normal on/off button.
Battery chargers keep drawing a little power after the battery is full. With Stop when full (on by default), the plug switches off when an appliance that was running has used almost nothing for ten minutes. It tries again at the next cheap period, or after one hour if the price stays green.
Technically: the appliance counts as running above 20 W and as finished below 3 W. This needs a plug that measures power, which all the listed plugs do.
Turn Stop when full off for an appliance that has long pauses but should keep its power, for example a dehumidifier that stops when the room is dry.
A plug that gives power by price must not get stuck on when it can't see the price. Two safety rules handle that:
The button still works offline, also right after a power cut: a press gives one hour of power, then the plug switches off again until the price is back. The plug counts the hour itself, so it doesn't need the internet or a clock for it.
Power when cheap switches the power off and on without asking the appliance. Only use it for appliances that are happy with that.
Stay within the plug's limit: for the Plug S Gen3 that is 2 500 W for a resistive load. Never use an extension lead or a multi-socket after the plug to go over it. Follow the appliance maker's charging advice: some batteries should not be charged unattended or at night.
Each price light shows the price now, its colour and where it sits on the colour scale. In Power when cheap mode you also see what the plug is doing:
| You see | What it means |
|---|---|
| ⚡ Power on | The price is cheap, the appliance has power. |
| ○ Power off | Waiting until the price is cheap (or normal, if you allowed yellow). |
| ⚡ Boost until 22:45 | Boost: on at any price (button or phone). |
| ○ Off until 22:45 | Someone pressed the button: off for one hour. |
| ✓ Finished | The charger has finished. Tries again at the next cheap period. |
| ⚠ No price | The plug can't reach SaveElectro, so its power is off for safety. |
"● Connected" means the plug checked in during the last half-hour. "Last seen" with a warning means it hasn't: check that it is plugged in and on Wi-Fi.
One script works for all choices; changes you make on My price lights (and Boost) reach the plug within about 10 seconds — it checks for them every 10 seconds; My price lights shows ⏳ until the plug confirms. New features sometimes need a newer script: paste it again when My price lights asks you to (One more step).
Run only one SaveElectro script per plug. If you created a second one, stop the old one and turn off its Run on startup. Also remove any schedules or auto-off timers you set up for the plug in the Shelly app, so they don't fight with Power when cheap.
| Feature | Free | Premium |
|---|---|---|
| Price lights | 1 | Up to 10 |
| Price colours, live status | ✓ | ✓ |
| Brightness, night dimming | ✓ (night 22–07) | ✓ (your quiet hours) |
| Power when cheap, button, stop when full, safety off | ✓ (cheap) | ✓ (cheap, or cheap and normal) |
| Your own colour limits | — | ✓ |
| "Pays for itself" blink by your full price | — | ✓ |
The plug hasn't checked in with this light's key. Check that the script is started on the plug. If it is, the key may be old: press New key, copy the new script and paste it over the old one.
It is on, but has no internet or can't get a fresh price. It turns white within about two minutes of losing the internet, and takes the price colour again within a minute or two of the internet coming back. Shelly's own red or blue blinking while it reconnects is normal. If it stays white with a working internet, check the Wi-Fi: open the plug's address shown on My price lights.
The plug picks up changes with its next price check, at most a quarter-hour later. To see it at once, stop and start the script on the plug.
The plug runs an older script. Press Install plug script and replace the script on the plug once (see Updating the script).
Either the charger finished (Stop when full: the status says Finished), someone pressed the button (Off until …), or the plug had no fresh price for 30 minutes. Press the button for an hour of power, or turn off Stop when full if the appliance has long pauses.
SaveElectro locks the Price Light plug with a password, so that system cannot connect to it and the two never work against each other. If you want the other system to switch this socket instead, choose 🔌 Always on in SaveElectro and give that system the plug's password (Show plug password on My price lights).
SaveElectro has locked the plug. User admin, password: Show plug password on My price lights. After a factory reset the plug is unlocked; SaveElectro locks it again with the same password within a minute.
That is Shelly's own start-up signal. The price colour returns within a minute.
Yes, within 14 days of receiving it, without giving a reason: Withdraw from contract here (you need the order number from your order email). A faulty plug is covered separately, also after the 14 days. See the Refund and Returns Policy.
One Shelly plug, one script, and the price is in the room with you. Free for one light.
Plug limits: Shelly: What's the difference between the Plug S, Plug M and Plug PM Gen3?