5 ms·

I guess the problem is with the price of the sensors. Just look how expensive the Aranet 4 home shown in article is. There are worse devices for less like the I

I guess the problem is with the price of the sensors. Just look how expensive the Aranet 4 home shown in article is. There are worse devices for less like the IKEA alpstuga. I also don’t know how much electricity they pull.

Gigachad 3mo ago
I got the ikea sensor, I’d say it’s way more accurate than you need for personal use. I wouldn’t use it as a scientific instrument but it’s well good enough to see if the room is ventilated enough. I was shocked to see just how fast CO2 climbs while in a room, and how just opening the window just a crack was enough to restore the room to baseline co2. The thing runs on usb 5v so the power consumption is negligible. It also plugs in to home assistant great.
- p-e-w 3mo ago
  > The thing runs on usb 5v so the power consumption is negligible. There’s a huge leap from that to the power consumption being low enough to be integrated into a smartphone, as demanded by OP.
  - progval 3mo ago
    I don't think power use is the issue. I have this cheap CO2 sensor: https://www.domadoo.fr/en/devices/5882-heiman-zigbee-air-quality-sensor-co2-temperature-humidity.html https://www.domadoo.fr/en/devices/5882-heiman-zigbee-air-qua... which draws 0.5W. This includes thermometer and humidity sensor, Zigbee transmission, and acting as a Zigbee router, but it gives us an upper bound. It also measures continuously (picks up someone breathing on it within 10s), which is overkill. A phone could measure CO2 levels once every 10 minutes which would average under 0.01W, so that would work. However, this assumes the sensor would fit in a smartphone, which is not a given. And these things need air flow. And they also wouldn't work while the phone is in a bag or a pocket.
    - nnevod 3mo ago
      >A phone could measure CO2 levels once every 10 minutes which would average under 0.01W, so that would work. Not sure about that, at least NDIR sensors have to be at certain elevated temperature to work and they do some preheating when you turn them on from standby. So it's not possible to just measure less often as then energy would have to be spent on heating the sensor.
  - ac29 3mo ago
    I've got a NDIR CO2 sensor about 6 weeks into a supposed 1 year battery life, still reporting 100% battery. Power use is very low since it only fires up the CO2 sensor every 30 mins.
- odiroot 3mo ago
  Can it work with Zigbee network or is Matter/Thread required?
  - embedding-shape 3mo ago
    I'm using a bunch of IKEA's "smart home" stuff, all via Zigbee+HA, works great. Look for the Zigbee icon on the package, and the pairing for Zigbee vs their own home controller might have slightly different pairing sequence on the device, otherwise it just seems to work.
    - deleted 3mo ago
      [deleted]
    - microtonal 3mo ago
      ALSTUGA does not work with Zigbee. They recently overhauled their lineup and replaced all Zigbee devices by Thread + Matter. Some of the new devices (mostly those who support TouchLink, e.g. some of the lights) have a secret pairing mode with which you can use them with Zigbee, but it's only a subset of the new products.
      - embedding-shape 3mo ago
        > They recently overhauled their lineup and replaced all Zigbee devices by Thread + Matter. Uuh, seems not keeping up with social media finally backfired. That sounds horrible! So far IKEA been a great experience when it comes to HA+Zigbee stuff, and I started buying stuff relying on they'd keep just keeping up with that, really sad to hear they've changed course. The "secret pairing mode" stuff sounds the same as currently/before though, but they only do so for a subset is new and hope they again change their mind.
        microtonal 3mo ago
        Yeah, I bought a bunch of INSPELNING smart plugs when they were clearing out the inventory. The new GRILLPLATS switches are more compact though, which is nice.
- microtonal 3mo ago
  I have HA send me a notification to ventilate my office when the air reaches 1000ppm CO2. The IKEA ALPSTUGA is often off by 300ppm even under 1000ppm. If I'd use it, I'd be getting notifications at 700ppm. It is a thermal conductivity sensor, which is a very indirect way of measuring CO2 and is very sensitive to environment factors. You only get somewhat good readings in lab conditions. Don't by the ALPSTUGA for anything but very rough trends, there are much better affordable options.
  - Gigachad 3mo ago
    Within 300 ppm is more than good enough. Realistically 1000 ppm is not that bad. The average meeting room is multiples of that. Also in my experience it’s much more accurate than that.
    - microtonal 3mo ago
      I notice that thinking becomes less clear when going above 1000ppm, so I let HA send a notification at 1000ppm. With ALPSTUGA it would send already at 700ppm. By the way, above 1000 the divergences become even larger due to the inaccuracy also being 10% of the ambient CO2 concentration (in optimal circumstances, probably larger IRL). So, suppose you want to be notified at 2000 ppm, the IKEA sensor might already do so at 1500 or 1600 ppm and it continuously drifts, so it's not like you can use a particular offset. Besides that, what's the point? There are much better meters in a similar price class. As an additional benefit, they can last months or up to a year on two AA batteries. ALPSTUGA is an inferior product.
      - summm 3mo ago
        Can you recommend some?
        microtonal 3mo ago
        Mentioned two here: https://news.ycombinator.com/item?id=48783879 https://news.ycombinator.com/item?id=48783879
Liftyee 3mo ago
I would hesitate to say the IKEA is worse. Inside the IKEA is a reputable Sensirion all in one sensor module. It's much cheaper and smaller because the CO2 sensor in it is using different (newer) technology that only released a few years ago from Sensirion. (Upd: the IKEA does have lower accuracy, with ±100 ppm instead of ±30 ppm. From the SEN63C datasheet)
- deleted 3mo ago
  [deleted]
- microtonal 3mo ago
  No, it is crap. Yes, it is Sensirion, but it uses a thermal conductivity sensor, which is a very indirect method of measuring CO2. One part of the sensor emits heat and the other senses it and the idea is that heat transfer changes with different CO2 concentrations. However, a lot of other factors influence this as well, such as ambient temperature/humidity (which is why the sensor incorporates measurements from an SHT sensor), but also gas mixture, etc. You only get good readings at lab conditions. Even below 1000 ppm, I would often see readings that are 300 ppm from more expensive, known-good CO2 meters. If you want a CO2 meter on the cheap, either wire up an optical NDIR sensor like the SenseAir S88 (22 Euro) up to an esp32, which is possibly the best sensor you can get for the money (slightly cheaper version of the sensor that the AraNet4 uses). Or if you want something standalone with a display, get the SwitchBot Meter Pro CO2 for ~50 Euro, which uses a photoacoustic NDIR, but is still miles better than the sensor in the ALPSTUGA. Can also be hooked up with HA through an ESPHome BLE proxy or with the SwitchBot Hub. You can find a comparison of the IKEA sensor with other affordable sensors here: https://danieldk.eu/hardware/smart-home/ikea-alpstuga https://danieldk.eu/hardware/smart-home/ikea-alpstuga (Upd: the IKEA does have lower accuracy, with ±100 ppm instead of ±30 ppm. From the SEN63C datasheet) You forget to mention that it is ±100ppm plus ±10% of the ambient ppm, which makes a big difference. At 1000ppm it's ±(100ppm + 0.10*1000) = 200ppm and that's only in an environment with 25C, 50% RH, and 1013 mbar. So, that does not tell you much, given that thermal conductivity is very sensitive to environmental factors.
  - nok22kon 3mo ago
SideburnsOfDoom 3mo ago
> I also don’t know how much electricity they pull. It can't be much, since the Aranet 4 can run for years on 2 AA batteries.
mdf 3mo ago
Ruuvi Air[1] seems to be close to the middle in both price and CO2 measurement accuracy between aranet4 and the IKEA device. I don't have personal experience with Ruuvi Air specifically, but have been using their cheaper Ruuvi Tags (that don't measure CO2) for temperature, humidity and air pressure measurement at home and office. [1] https://ruuvi.com/air/ https://ruuvi.com/air/

Gigachad 3mo ago

I got the ikea sensor, I’d say it’s way more accurate than you need for personal use. I wouldn’t use it as a scientific instrument but it’s well good enough to see if the room is ventilated enough. I was shocked to see just how fast CO2 climbs while in a room, and how just opening the window just a crack was enough to restore the room to baseline co2. The thing runs on usb 5v so the power consumption is negligible. It also plugs in to home assistant great.

p-e-w 3mo ago
> The thing runs on usb 5v so the power consumption is negligible. There’s a huge leap from that to the power consumption being low enough to be integrated into a smartphone, as demanded by OP.
- progval 3mo ago
  I don't think power use is the issue. I have this cheap CO2 sensor: https://www.domadoo.fr/en/devices/5882-heiman-zigbee-air-quality-sensor-co2-temperature-humidity.html https://www.domadoo.fr/en/devices/5882-heiman-zigbee-air-qua... which draws 0.5W. This includes thermometer and humidity sensor, Zigbee transmission, and acting as a Zigbee router, but it gives us an upper bound. It also measures continuously (picks up someone breathing on it within 10s), which is overkill. A phone could measure CO2 levels once every 10 minutes which would average under 0.01W, so that would work. However, this assumes the sensor would fit in a smartphone, which is not a given. And these things need air flow. And they also wouldn't work while the phone is in a bag or a pocket.
  - nnevod 3mo ago
    >A phone could measure CO2 levels once every 10 minutes which would average under 0.01W, so that would work. Not sure about that, at least NDIR sensors have to be at certain elevated temperature to work and they do some preheating when you turn them on from standby. So it's not possible to just measure less often as then energy would have to be spent on heating the sensor.
- ac29 3mo ago
  I've got a NDIR CO2 sensor about 6 weeks into a supposed 1 year battery life, still reporting 100% battery. Power use is very low since it only fires up the CO2 sensor every 30 mins.
odiroot 3mo ago
Can it work with Zigbee network or is Matter/Thread required?
- embedding-shape 3mo ago
  I'm using a bunch of IKEA's "smart home" stuff, all via Zigbee+HA, works great. Look for the Zigbee icon on the package, and the pairing for Zigbee vs their own home controller might have slightly different pairing sequence on the device, otherwise it just seems to work.
  - deleted 3mo ago
    [deleted]
  - microtonal 3mo ago
    ALSTUGA does not work with Zigbee. They recently overhauled their lineup and replaced all Zigbee devices by Thread + Matter. Some of the new devices (mostly those who support TouchLink, e.g. some of the lights) have a secret pairing mode with which you can use them with Zigbee, but it's only a subset of the new products.
    - embedding-shape 3mo ago
      > They recently overhauled their lineup and replaced all Zigbee devices by Thread + Matter. Uuh, seems not keeping up with social media finally backfired. That sounds horrible! So far IKEA been a great experience when it comes to HA+Zigbee stuff, and I started buying stuff relying on they'd keep just keeping up with that, really sad to hear they've changed course. The "secret pairing mode" stuff sounds the same as currently/before though, but they only do so for a subset is new and hope they again change their mind.
      - microtonal 3mo ago
        Yeah, I bought a bunch of INSPELNING smart plugs when they were clearing out the inventory. The new GRILLPLATS switches are more compact though, which is nice.
microtonal 3mo ago
I have HA send me a notification to ventilate my office when the air reaches 1000ppm CO2. The IKEA ALPSTUGA is often off by 300ppm even under 1000ppm. If I'd use it, I'd be getting notifications at 700ppm. It is a thermal conductivity sensor, which is a very indirect way of measuring CO2 and is very sensitive to environment factors. You only get somewhat good readings in lab conditions. Don't by the ALPSTUGA for anything but very rough trends, there are much better affordable options.
- Gigachad 3mo ago
  Within 300 ppm is more than good enough. Realistically 1000 ppm is not that bad. The average meeting room is multiples of that. Also in my experience it’s much more accurate than that.
  - microtonal 3mo ago
    I notice that thinking becomes less clear when going above 1000ppm, so I let HA send a notification at 1000ppm. With ALPSTUGA it would send already at 700ppm. By the way, above 1000 the divergences become even larger due to the inaccuracy also being 10% of the ambient CO2 concentration (in optimal circumstances, probably larger IRL). So, suppose you want to be notified at 2000 ppm, the IKEA sensor might already do so at 1500 or 1600 ppm and it continuously drifts, so it's not like you can use a particular offset. Besides that, what's the point? There are much better meters in a similar price class. As an additional benefit, they can last months or up to a year on two AA batteries. ALPSTUGA is an inferior product.
    - summm 3mo ago
      Can you recommend some?
      - microtonal 3mo ago
        Mentioned two here: https://news.ycombinator.com/item?id=48783879 https://news.ycombinator.com/item?id=48783879

Liftyee 3mo ago

I would hesitate to say the IKEA is worse. Inside the IKEA is a reputable Sensirion all in one sensor module. It's much cheaper and smaller because the CO2 sensor in it is using different (newer) technology that only released a few years ago from Sensirion. (Upd: the IKEA does have lower accuracy, with ±100 ppm instead of ±30 ppm. From the SEN63C datasheet)

deleted 3mo ago
[deleted]
microtonal 3mo ago
No, it is crap. Yes, it is Sensirion, but it uses a thermal conductivity sensor, which is a very indirect method of measuring CO2. One part of the sensor emits heat and the other senses it and the idea is that heat transfer changes with different CO2 concentrations. However, a lot of other factors influence this as well, such as ambient temperature/humidity (which is why the sensor incorporates measurements from an SHT sensor), but also gas mixture, etc. You only get good readings at lab conditions. Even below 1000 ppm, I would often see readings that are 300 ppm from more expensive, known-good CO2 meters. If you want a CO2 meter on the cheap, either wire up an optical NDIR sensor like the SenseAir S88 (22 Euro) up to an esp32, which is possibly the best sensor you can get for the money (slightly cheaper version of the sensor that the AraNet4 uses). Or if you want something standalone with a display, get the SwitchBot Meter Pro CO2 for ~50 Euro, which uses a photoacoustic NDIR, but is still miles better than the sensor in the ALPSTUGA. Can also be hooked up with HA through an ESPHome BLE proxy or with the SwitchBot Hub. You can find a comparison of the IKEA sensor with other affordable sensors here: https://danieldk.eu/hardware/smart-home/ikea-alpstuga https://danieldk.eu/hardware/smart-home/ikea-alpstuga (Upd: the IKEA does have lower accuracy, with ±100 ppm instead of ±30 ppm. From the SEN63C datasheet) You forget to mention that it is ±100ppm plus ±10% of the ambient ppm, which makes a big difference. At 1000ppm it's ±(100ppm + 0.10*1000) = 200ppm and that's only in an environment with 25C, 50% RH, and 1013 mbar. So, that does not tell you much, given that thermal conductivity is very sensitive to environmental factors.
- nok22kon 3mo ago

SideburnsOfDoom 3mo ago

> I also don’t know how much electricity they pull. It can't be much, since the Aranet 4 can run for years on 2 AA batteries.

mdf 3mo ago

Ruuvi Air[1] seems to be close to the middle in both price and CO2 measurement accuracy between aranet4 and the IKEA device. I don't have personal experience with Ruuvi Air specifically, but have been using their cheaper Ruuvi Tags (that don't measure CO2) for temperature, humidity and air pressure measurement at home and office. [1] https://ruuvi.com/air/ https://ruuvi.com/air/