Following a few days with all the windows closed (thanks cold weather), I’ve started looking into devices I could integrate for (mainly) Co2 monitoring.
I thought other people might benefit from the information I’ve gathered, since it’s not much more effort beyond me just doing the research.
I haven’t purchased quite yet, and may add an update when I do.
Prices are in GBP.
Option 1: Random-name amazon/alibaba jobbies.
- Price: £20-40
- Connectivity to hass: WiFi or Zigbee.
- Sensors: Co2, VOC, Temperature, Humidity, PM2.5 (allegedly…)
- Pros: Very cheap.
- Cons: Data returned is effectively useless, when it gets returned at all.
- These sensors generally don’t have a proper Co2 sensor, and instead estimate it from a VOC reading.
I nearly bought one of these a few times, fortunately there is now more data about them.
Once I have my proper solution, I may buy one just to chart how off they are!
As a main device, I would not buy any of these.
Option 2: Awair Element
- Price: £160 new, £70-110 second hand
- Connectivity to HASS: Local API or network API over WiFi.
- Sensors: Co2, VOC, Temperature, RH, PM2.5
- Pros: Decent sensors, integrates with HASS via a local API. AQI read-out on the device itself.
- Cons: Users report wifi issues, which the manufacturer isn’t acknowledging.
This can mean periods where the data is not reported.
Firmware is closed source, specifications of sensors are not stated (but have been found unofficially)
These are not a bad solution, so long as you are happy dealing with a WiFi device and an API back-end that is closed source.
There is a slightly insane history to the Awair .
When they first released, they could contribute to a system called PlanetWatch, which paid tokens in exchange for readings.
These tokens (somehow) had value, so people started…Yep, they started buying multiples, and mining with them.
This has now ceased, afaik, so there is good second hand supply.
I’m hesitating a little, just because of the reports of wifi issues, which coupled with a potentially problematic wifi connectivity, could leave me with a brick one day.
Option 3: AirGradient (Open Air and One)
- Price including shipping: £120 for the Open Air, £135 for the One
- Connectivity to HASS: ESPHome via WiFi/BT.
- Sensors: Co2, VOC, Temperature, RH, PM2.5
- Pros: Open Source, maintainable, specifications and accuracy clearly stated.
- Cons: A little pricey, availability in Europe not known.
I like this one, and honestly, I could see myself buying it.
I rather like the OLED display on the ONE, too.
They also offer a more basic build-your-own without VOC detection for about £60
Option 4: Roll-your-own, with an ESP32 and an SCD30
- Price: £70 for the SCD30, £10 for the esp.
- Sensors: Co2 and RH
- Connectivity to HASS: ESPHome via Wifi/BT (or whatever you want)
- Pros: Open source, maintainable, specifications and accuracy clearly stated. Most accurate.
- Cons: A little work required, only tests Co2 and RH.
I would definitely consider this, however, it’s not that much more for the more featured AirGradient. A cheaper option would be using a SensAir S8, at around £40, which is still as accurate as the AirGradient.
Option 5: Air-q
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Price: £280 for Light, £390 for Basic, £540 for Pro
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Sensors:
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Light: Co2, VOC, Temperature, Noise, RH, AH.
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Basic: As Light, plus CO, KPa, PM1/2.5/10.
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Pro: As Basic, plus O2, O3, SO2, N02
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Connectivity to HASS: Native integration over WiFi, local network.
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Pros: Very comprehensive sensor array. Specifications and accuracy clearly stated. Simple Good/bad LED readout on the device.
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Cons: Oof, that’s expensive. Closed source.
If I had unlimited money, I’d probably get one of these, because it’s pretty damned comprehensive.
And I definitely respect them for making a turn-key “it does everything out of the box” solution, and completely understand that’s why it’s expensive.
I am in central Europe and I have both the AirGradient One and the AirQ Basic. The AirQ is much more capable, with more sensors (especially a dedicated VOCs sensor), and has a better design, and the Home Assistant integration works really well locally. It is quite expensive though.
The AirGradient One took a long time to ship (almost three months, but that was expected and communicated clearly by the AirGradient folks) but it definitely is available for shipping to Europe, so probably also the UK. It has fewer sensors but you can (and I did) flash it and customise it with Esphome. Look for the github repos of user MallocArray. So it also works very well locally, using the esphome integration.
So it really depends on what you want to measure. If it is just Co2 and pm2.5 then the AirGradient is probably enough and much cheaper. With the AirQ you pay a lot more but you get many more sensors.
Recently received an AirGradient One. Added it to HA via ESPHome. The setup was pretty smooth. It shows the following sensors in HA:
- CO2
- Humidity
- NOx Index
- PM 0.3
- PM 1.0
- PM 10.0
- PM 2.5
- PM 2.5 AQI
- Temperature
- VOC Index
I have four Awairs and I’m happy with them for now. Snagged at $50/ea.
Edit: for -> four
I may set up some eBay alerts in that case! As multiple sensors certainly wouldn’t be a sad thing.
I’ve got a Qingping Air Monitor Lite - it’s small, not ugly, and from what I read at the time, has a decent CO2 sensor. It integrates perfectly with Home Assistant via Bluetooth. Seriously, no issues once I got it setup - which I believe did require their app to do initial setup/updates/etc… https://www.home-assistant.io/integrations/qingping/ https://www.amazon.ca/Qingping-Monitor-Compatible-Temperature-Humidity/dp/B092HK4BB1
I have done 3 and 4, and I definitely prefer the air gradient, it is a nice sleek little box that is flashable with esphome making it tie directly into HASS. Will be getting more of them in the near future.
Apollo AIR-1 seems like a good option. Open source software and hardware.
It seems very nice! Do you have it? How is it? Do you know what gasses the gas sensor measure?
I don’t but I have a couple of the presence sensors from the company and like them a lot. They sort of require some tuning but have been quite reliable since.
I have a ‘roll-your-own’ using an adafruit SCD-30 module https://www.adafruit.com/product/4867 IR-based CO2, temp & humidity; I2C with python libraries, so integrating it with an RPi is easy. Sensor is self-calibrating over time, so if you leave it in a higher CO2 space with no exposure to fresh air, it will eventually drift such that the lowest observed CO2 reports as 420 ppm. Newer SCD-40 is only $45, but different sensor technology.
Dunno about their shipping outside the US.
I have a few airthings pluses. They’re pricey, but work with ha and flawlessly. And they measure just about everything you can.
There is an easily hackable and cheap device from IKEA by the name of “VINDRIKTNING”. There are YT videos on how to wifi-enable that thing and integrate it into home automation services.
i’ve got one and hacked it with an ESP32. it’s awesome, but it’s not a CO2 sensor, it detects fine particles in the air.
I stand corrected. Thank you!