Archives 2024

Besides all the automation that you can do with Home Assistant it also has a very nice Energy Usage dashboard to keep track of everything going on in your house. Having historic data is always good, especially if you don’t yet have any solar or a house battery so you can size the systems properly.

My setup keeps track of my grid electricity and gas usage thanks to a smart meter, solar via a couple of raspberry Pi, and water thanks to the fact that water meters broadcast their reading unencrypted!

Electricity and Gas

I finally relented last year and got a smart meter. My electricity is with British Gas and they rather cheekily just booked a meter replacement appointment without me asking. I decided to keep it rather than cancelling it as I’m a sucker for tech! I was put off because my existing meter would actually run backwards if I was generating more than I was using.

With the meter installed, it comes with a readout to show you how much you are currently using. Its not quite straight forward to get the details into Home Assistant. You can sign up on an app called Bright and get half hourly meter readings for free, and this has an integration built into Home Assistant. This is a nice quick way of getting the data but it isn’t very granular.

Alternatively you can get a different display from Hildebrand that not only will read your meter for instantaneous data, but also connects to your wifi and provides data via an MQTT connection to Home Assistant, with an associated integration.

Once connected, you can add the relevant entities into the Energy dashboard.

Solar

I have two relatively small grid tied solar installs (limited by the amount of roof space), one on the garage and one on the main roof both using Solis inverters. The problem with these inverters is that the default method of logging the data writes all the info off to a third party in China. Now I’m not necessarily a security nut, but I do like to avoid cloud based services wherever possible.

Thankfully, the logging stick that comes with the inverter actually just reads RS485 (modbus) registers. After much trial and error due to lack of decent documentation (or more to the point, documentation that actually agrees!) I managed to write a python script which reads the registers and posts the data to MQTT using the Home Assistant auto discovery layout.

This script is running on a PiZeroW, using the connector off the standard logging stick. I did ask if they had any broken sticks to save wasting a working one, throwing away all the electronics.

Water

The last bit of the puzzle for my house was a bit of a long shot. When we moved in we decided to go with a water meter due to the rates for our area being way too high. I didn’t think much of it, but as I now had a smart meter for gas and electric, plus all the solar being logged into Home Assistant, I thought I’d take a look. The fact that the Energy dashboard had a section for water definitely had a influence!

After wiping off a rather thick layer of dust from the meter, I got the model number and started looking things up about it. Turns out it broadcasts the meter reading on a standard 868Mhz, which of course can be listened in on using a simple, cheap USB digital TV dongle. I may have a few of them laying around the house (including one listening in to all the planes passing overhead). Even better, it was unencrypted.

Thankfully I didn’t have to write everything myself, there is already an open source program call wmbusmeters that will use an RTL dongle and output the data in JSON to the stdout. With a quick python wrapper to read that data and post it via MQTT for Home Assistant to read (again, using the auto discovery layout)

Energy Dashboard

All the entities created are then entered into the relevant sections in the Energy Dashboard. This automatically configures everything to display and record the information. It gives a nice page to view all the data. I’ve also got a number of devices hooked up with plug in energy meters so I can see the consumption of things like my server rack, computer, tv, etc. All of these will also get displayed on the dashboard.

Along with the dashboard, I also have graphs in Grafana for more granular details and spotting trends.

Future

At some point I want to possibly get a battery for the house. Once I’ve collected a year or so of data I’ll have a much better idea on the suitable size to get and should be able to calculate a fairly accurate ROI. For now I’m just happy to keep track of the energy usage.

As the weather is still terrible around here, I spent the weekend working on my home automation. A load of general maintenance such as replacing batteries and fixing broken things like the integration with the burglar alarm.

I also added a few new integrations:

• DVLA Link – This lets me query details about our cars, and more specifically the due dates for MOT and insurance.
• Waste Management – Link into the local government to know when and what type of refuse collection is coming up.

But, the most fun one was finally getting the 10 inch display and Raspberry Pi mounted on the wall as a custom control panel!

I’ve had it sat on my desk for about six months and decided it was actually time to get it done. I had to CAD up a box for wall mounting and hiding the electronics. Not the best design, and lots of things to improve, but its functional.

A quick couple of holes in the wall, and it was mounted.

Once I have the local voice assistant details finished, this will get that installed too. That will need a redesign of the case to support some speakers and volume controls. The actual dashboard needs a bit more work, and possibly an LCARS theme as an option.

But at least its off my desk and working now. Very handy for a quick glance at the calendar, weather, alarm status, and also to view the front door camera.

Over the years I’ve messed with various home automation systems. From X10 in the early 2000’s, through Mi Casa Verde and z-wave going into the 2010’s, a few years using OpenHAB, up to the current day where I’m using Home Assistant.

Home Assistant has been around for a while, but I was loathe to move from OpenHAB as I already had a lot set up. However, as OpenHAB fell behind I finally bit the bullet and installed HAOS on a spare Raspberry Pi. This turned out to be a good thing.

I’ve been using it now for a couple of years, and it works really well as a central hub for all the different technologies in the house. This post is a quick overview of what I have set up.

Technologies

The beauty of Home Assistant is that it acts as a hub for many different home automation protocols, devices, and other information. A quick list of technologies I have integrated:

• Zigbee
• Z-wave
• ESPHome
• Matter
• Thread
• MQTT
• WLED

But not only does it talk to these home automation systems, it can also tie into other things such as:

• 3d Printers (Octoprint, Klipper, Bambu Labs)
• Google Assistant (Ties your home automation into google voice commands)
• Jellyfin/Plex
• Fitbit
• Raspberry Pi
• Roomba
• Smart Meters
• Printers (you know, the none 3d kind)
• Frigate (CCTV)
• Solar Production

And lastly, you can pull in information from web APIs to help with automations:

• Weather
• Sunrise/Sunset
• Moon phases
• Astronomy Weather (More detailed weather more geared to astronomers)
• Github (Monitor commits, issues, etc.)
• Whois (Keep an eye on domains expiring)
• DVLA (MOT and insurance due dates)
• Waste Management (get dates and types of refuse collection)

This is a lot of tech, and this isn’t a complete list of everything I have tied in, just the majority.

My Setup

So, enough of what it can talk to. How is my house set up?

Core

The main core of the system is a Raspberry Pi 4 running Home Assistant OS. This is a simple install onto a Pi and is fully managed by Home Assistant. Everything runs in containers and gives you everything you need to get started.

The Pi is run from PoE in a rack, to keep things simple, and also has everything installed onto an SSD drive as it is a lot more reliable that using an SD Card (My old OpenHAB system was on SD Card and I had to rebuild it every now and again as the SD card wore out). Plugged into the Pi are two USB dongles, one for z-wave and one for Zigbee/Matter. This direct connection lets me control the majority of the devices I have.

Also, installed as part of HA OS I have a few other addons. These are:

• InfluxDB – This keeps a historical record of all the stats in the house, which can then be pulled out into a Grafana Dashboard
• Mosquitto MQTT Broker – Some devices talk directly to an MQTT server, so this is running to fill that role
• ESPHome – A system designed to convert simple ESP32 or ESP8266 boards into home automation devices using a simple yaml language. Some commercial devices can also be flashed with ESPHome for extra functionality.
• HA Google Backup – Backups!!
• Lets Encrypt – Automatically renews my SSL cert
• VaultWarden – A locally run version of Bitwarden password manager.

These are all running on the same Pi quite happily.

CCTV (Frigate)

I have a second Pi 4 running a system called Frigate. This is an open source CCTV system that integrates really nicely with Home Assistant. It also has functionality for not only motion detection but facial detection too so that it will only trigger if it detects a human (not a cat or squirrel) which definitely helps cut down on false positives. I have had to block out certain areas for detection tho, as in high winds it sometimes thought some of Joy’s flowers were a human!

I’m hoping to upgrade this to a Pi 5 when the PoE hat comes out, as I currently have 4 cameras going into it and it does struggle a bit. I do have a USB Coral AI stick from Google that I can offload some of the more AI related tasks too.

NAS (TrueNAS Scale)

I do have a NAS box set up that has a simplified Kubernetes system installed. On this I run a few other services, including Grafana for viewing stats of my home, Spoolman which keeps track of my 3d printer filament usage, and Trilium Notes for keeping track of the random things in my brain.

Other Hardware

So what have I actually got set up?

Most of the main lighting in the house are Phillips Hue lights, with their dimmer controllers. However, since realising just how much data the Hue hub was sending back, I removed that and now everything is directly controller via Zigbee. The only main exception to this is the garage which initially had fluorescent tubes and I use a z-wave in wall module to control that.

I’ve a lot of smart sockets around the house too, from plugin units to actual in wall faceplates. The vast majority of these allow for energy usage collection too so I can not only turn things on and off remotely, but I can also monitor the energy usage of various items such as 3d printers, server cabinets, desktops, TVs, etc.

The burglar alarm is also connected in, which turns all the various door and motion sensors into sensors that Home Assistant can use for automations.

WLED is a system to install onto an ESP8266 or ESP32 to control a string of RGB LEDs. I’m starting to incorporate more of these into the setup and they tie very nicely into Home Assistant

Control

What does all this gain me? The main benefit is a single app on my phone to control everything. I don’t need a Hue app, a Roomba app, to access a webpage to control my WLED lights, etc. I can create a dashboard on Home Assistant to give me a nice overview of the controls in the house. For instance, my setup main dashboard consists of an overview page (simple controls such as lights, along with main thermostat control and some other status) with the ability to click a room and get more detailed controls and information. That covers about 90% of everything.

Along with this, as I have Google Assistant integrated, I can also just ask google to turn lights on, set the thermostat, etc.

Automations

So far, most of the stuff is just allowing for remote control, but the real beauty is making things automatic. I’ve only really got some basic automations done at the moment and want to expand on this in the future.

• Automatic outside lights. I have the lights set to come on at sunset, and turn off at midnight. They’ll also come on in the morning if Joy is going to work and its still dark out.
• Turn the thermostat down at night. The thermostat will drop a couple of degrees at midnight whilst we’re asleep to save some energy. I have got the alternative set to turn it back up in the morning, but thats disabled for now as its just as easy to turn it up manually depending on what time we get up.
• Send an alert if someone comes to the front door, and turn the light on. This is one of the reasons I want to upgrade the Frigate Pi. The Pi 4 is just a little slow on this, and hoping the extra processing power will speed things up.
• Show video feed on my google home displays when someone is detected on the front door camera.
• Automatic office lights. I’m terrible at remembering to turn my light off in the office, so I have a simple motion detector to automatically turn the lights on and off. They do turn off occasionally if I’m in the office concentrating on something and not moving much (such as writing a blog post about my home automation system) so I’ve just ordered some mm wave detectors to try which should be more sensitive.
• Notifications when prints have finished or theres an issue.
• Daily notification if a battery is low in a device. All my Phillips Hue Dimmers were bought at the same time, and I’ve just had to replace all the batteries at once!

Theres room to do a lot more of course, but these will do for now.

Monitoring

So, I’m a nerd and I like stats. One of my favourite things that Home Assistant does is store historical data so that I can pull information out and graph it in Grafana. I’ve no idea if this will have future uses, but it does produce some pretty pictures such as the one on the left that shows temperature and humidity over time.

Also, Home Assistant has an inbuilt energy dashboard. You can select the various entities you monitor for energy usage from smart meters or solar panels, and it will generate a nice dashboard to show your energy usage.

Water consumption is on there because it seems UK water meters broadcast their readings unencrypted on a band that can be read with a cheap USB dongle. I wrote some python to read the meter and push the stats into Home Assistant. I also wrote some software to run on a Pi connected to my two solar systems to read the meter information there and push it into Home Assistant.

I’m hoping once I’ve collected data for a full year, I can work out if I can get a decent ROI on a house battery.

Future Plans

One of the big things at the moment is LLMs (I won’t call them AI!) and Home Assistant can actually make use of them right now. This means I can replace all my spyware Google Homes with a fully local solution running on some low powered Raspberry Pi zeros, using a local LLM for more natural language communication. Plus you get the ability to add custom wake words, which will be fun.

I’ve also got a Pi with a 10 inch display on my desk that I want to turn into a control panel to put somewhere in the house, possibly in the entrance way.