[Hobohodo]

Would you be able to share where you might get such a cheap CO2 sensor/the name of it? I've had trouble finding them for less than £60 in the UK and would like to set one up.

[gsich]

MH-Z14 or Z19 are cheap, but not 8$ cheap, more like 25.

[sbr464]

https://www.co2meter.com/collections/sensors has a bunch of different ones, I usually look on Mouser also. I don't have a name of one currently. I've been using the particle.io platform with a particle device/LTE for sending out data and programming them.

[gsich]

None of them are in the 8$ range. There also seem to some copies which are way overpriced.

[sbr464]

Interesting to have an arbitrary $8 price point. You only live once, get the best!

[gsich]

Not my restriction.

[bhouston]

I always check aliexpress.com https://www.aliexpress.com/wholesale?SearchText=co2+sensor+m...

[RossM]

Adafruit sell a 1-60,000 ppm equivalent-CO2 sensor for £15. https://www.adafruit.com/product/3709

[aaaaaaaaaab]

This doesn't measure CO2 levels. It measures volatile organic compounds and calculates the amount of CO2 that would cause the same greenhouse effect.

>The SGP30 does have built in calibration capabilities, note that eCO2 is calculated based on H2 concentration, it is not a 'true' CO2 sensor for laboratory use.

[janekm]

Not even that. It is designed for hvac applications and measures VOCs on the assumption that they are from human breath and have a corresponding increase in CO2 levels due to breath.