Developer: Neil K's Plugins
Category: Energy Monitoring
Github: Github Repo
Assistance: Get help!    Check the online documentation
Plugin ID: com.barn.indigoplugin.GlowmarktCAD
Latest release: v0.0.13 released on Oct. 24, 2020
Release downloaded: 0 times
Requires: Indigo v7.0.2 or higher
(Check the Releases tab below for older releases that may have different requirements)
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An Indigo Plugin that integrates with the Glowmarkt "Smarter Meter" service and specifically their combined "In Home Display" (IHD) and "Consumer Access Device" (CAD) available from Hildebrand Technology Limited.

I have no affiliation with Glow, Glowmarkt or Hildebrand Technology Ltd, this plugin is not endorsed or supported by them, it does use their API's and MQTT service. It is provided on an as is basis as a community contribution.

The Glow combined IHD and CAD replaces the very limited IHD that was probably supplied when you had your smart meter installed. Even without Indigo integration, this is already a huge improvment providing real time "Bright app" based access to your energy usage (for Gas it is a little less real time due to the way the metering works, and the Gas meter being a battery operated slave to the powered smart electricity meter). The Glow CAD/IHD connects to the Smart Meter Personal Area Network (PAN) via Zigbee, but you cannot access this data locally or pair your own devices to the meter. Hildebrand can as they are licensed to access the DCC (the infrastructure than all energy suppliers must use to collect smart meter data, and to enable simple Smart Meter switching without losing "smartness" on the way). As a result with the latest generation SMETS2 meters (as all new ones must be) you can access your consumption data independenlty of your supplier, and gain access to all of it not just the limited information your supplier may share and in real time. You cannot access the Zigbee data directly, it has to go to Hildebrand's infrastructure (The Glow IHD/CAD connects to your wifi to enable this), but they provide the data back in the form of an API and an MQTT service. The first version of this plugin utilises both the MQTT data and the API.

The plugin consumes the payload sent from the associated MQTT service and builds on the excellent work by one of the Indigo Communities most prolific contributors (flyingdiver). You do not need to learn anything about MQTT beyond downloading the MQTT Broker Plugin and configuring it (for which I will provide detailed instructions). It also optionally uses the Glowmarkt API to pull historical data, and is then useful for people who do not wish to invest in the CAD hardware to gain real time access. If you do not have a CAD you will only be able to access data from the previous day, but you can do this with a free account, and without relying on your energy provider. Some of this functionality overlaps with my Octopus Energy Plugin but this is intentional as it removes the dependancy between energy providers and hardware to the largest extent possible. It does mean you can compare the two data sources to ensure consitency as they way the data is collated is different even though the source was your smart meter.

The UK Smart Meter implementation started with first generation "SMETS1" meters that were essentially tied to a specific energy supplier, and that in many cases reverted to being "dumb" if you changed energy suppiers. Hildebrand produce the "GlowStick" that interfaces with SMETS1, but I do not have access to a device to test, but I am happy to work with someone if they send me a copy of the relevant JSON payload from MQTT service (and I can explain how to do that in Indigo). These are being migrated to the DCC which should allow them to work, but I will need to work with users to test this.

The plugin appears as an energy monitoring device in Indigo that also shows the "real time" electricity consumption in Watts, which is updated every few seconds when a MQTT payload arrives. It also shows historical consumption for gas and electricity across various periods (Day/Month/Year) that are available in the MQTT data. (and potentially more via the API in the future). I have also integrated it with my Octopus energy plugin so that you can project an "hourly" electricity cost based on your actual current usage. All of these stages can be graphed, trigger on high usage/cost to shape demand and many more approaches I have not considered. It essentially allows you to control when you consume energy, to alert your family the best times to consume energy. This has broader benefit than cost optimisation, as the times of low rates also coincide with good availability of renewable energy.

I have also configured this to work with the excellent Grafana plugin giving near real time graphing of energy usage and cost, as well as with My Octopus Energy Plugin.

Documentation is

The current versions are tested but only by myself at this stage, and by using it then you may experience errors, including on the interpretation of the data (that is done by the plugin) but you will help me test and validate this.

Known Limitations : I cannot test against a SMETS 1 Meter and Hildebrand's glow stick. This is likely to impact the MQTT real time functionality, but with a little cooperation in testing it should be possible to address this very quickly. The other area that may be different is between SMETS1 which reports Gas Usage in kWH and SMETS2 which reports in Cubic Meters. My understanding is the API does the necessary conversion, but again I cannot validate that assumption

Release details
Released on: Oct. 24, 2020
Requires: Indigo v7.0.2+
Downloaded: 0 times 
Changes in this release

Fixes and issue of an uncaught error if the Glowmarkt API is not available. No other functionality changes

Release details
Released on: July 4, 2020
Requires: Indigo v7.0.2+
Downloaded: 0 times 
Changes in this release

This version adds no new functionality but adds meaningful state labelling for the device states for each 30min Cost or Consumption status. The initial version each state was labelled "Electricity State" which with 48 of them was not helpful when trying to create control pages. In this version they appear as "Consumption from 00:00" etc, which is a compromise as the same states are used for Cost and Consumption data depending on the device configuration. Given this only impacts Trigger or Control Page state labels it is reasonable but open to other suggestions.

Release details
Released on: June 28, 2020
Requires: Indigo v7.0.2+
Downloaded: 0 times 
Changes in this release

This version is stable but has not been tested by other users. Issues may occur but I will monitor closely.


This version has not been tested with the Glowstick which supports UK first Generation Smart Meters (SMETS1), the API functionality will work but we may need to work together to validate the MQTT instantaneous consumption, I will respond to questions on the forum as quickly as possible