The price light

The Plus Plug UK and the Plug S have a ring of light round the socket. The plugin can colour that ring by the price of electricity, so you can see at a glance whether now is a good time to put the washing on:

Ring colour Means
Green The cheap rate — below Cheap Below, 20p a unit to start with
Amber The standard rate — anything between the two
Red The peak rate — above Peak Above, 30p a unit to start with

The ring is bright while the plug is switched on, and dim while it is off, so you can still tell which plugs are on.

What it needs

The plugin does not fetch prices itself. It reads them from an Indigo variable that something else keeps up to date — another plugin, or a script of your own. It can use either or both of these:

  • A list of the day’s rates, in the form Octopus Energy publishes them: a list in JSON text with a start time, an end time and a price including VAT for each period, under the names valid_from, valid_to and value_inc_vat. With this, the ring changes on the minute the rate does. You can give it today’s rates and tomorrow’s rates in two separate variables.
  • The price now, as a number of pence per unit. The plugin uses this when there is no list, or when the list does not cover the present moment.

Setting it up

  1. Open Plugins → Shelly Direct → Configure and tick Show Electricity Price on Plug LED Rings.
  2. Choose the variables in Today’s Rates (variable), Tomorrow’s Rates (variable) and Current Price (variable). Leave any you do not use on - none -.
  3. Set Cheap Below (p/kWh) and Peak Above (p/kWh) to suit your tariff, and click Save.
  4. Choose Plugins → Shelly Direct → Show Electricity Price on All Plugs. The Event Log says which plugs now show the price, and which have no ring.

To do it one plug at a time instead, double-click the plug in Indigo and tick Show Electricity Price on LED Ring.

How it behaves

  • The plugin works out the price once a minute, and changes the ring only when the band changes.
  • A plug that is switched off at the wall, or away, is brought up to date when it comes back.
  • The first time the plugin colours a ring, it notes how the ring was set up, and puts it back exactly as it was when you untick the plug or choose Plugins → Shelly Direct → Stop Showing Electricity Price on Plugs.
  • Untick Show Electricity Price on Plug LED Rings in the plugin’s settings and every ring goes back to how it was.
  • If the menu item cannot reach a plug to find out whether it has a ring, it ticks it anyway, and the ring shows the price when the plug is back, if it has one.
  • Each time the band changes, the plugin’s own log notes the new rate and the price.