Outdoor Air Quality sensor for my town

Summary

It’s a AirGradient Air Quality sensor for the outdoors. It can tests a variety of air quality metrics, mostly notably CO2 which is one of the most looked at metrics for air quality. I know high CO2 levels are higher in cities and urban neighbourhoods and that CO2 is very bad for the human body; it causes fatigue, anxiety and confusion for most people. I’m excited to build it because I’ll get a real, hand on experience with soldering and electrical circuitry. My town isn’t too small but not as big as a large city with multiple air quality sensors already existing. I’m planning on putting the sensor outdoors and creating a website (with probably Svelete) and sharing it on my towns’s Reddit page as a way for people to see the real-time air quality metrics of real, realistic, neighbourhoods inside the town.

Plan

I have a few friends and family that are great with soldering that can teach me some things. I’ll need a soldering iron and some solder which I recently recieved for Christmas. Well thinking of soldering all the parts first, configuring everything, ensuring that it can work in low temperatures (-20C), creating a docker to monitor and log the information, then maybe if I have enough time finally creating the website in Svelte to share with my town. I actually attempted this project early last year but ran into some issues with the solder I was using; the solder was way to thick and I believe did not have a rosin core causing it to melt a lot slower. In my past experiences, I know both the micro-controller and LCD screen are fairly easy to short out and break in the past so I included another one for good measure. Now that I have a new & good soldering iron and solder, a friend that is very good with soldering, I think I’ll do pretty well.

For clarification all the parts I’m purchasing are apart of a guide that has full instructions on assembly. Jeff Geerling did a video on the project and that is what inspired me.

Budget

For both the PCB and the outdoor enclosure, I already own so I gave a rough estimate on how much it cost. I don’t think there is any sales tax for the ones on AliExpress. All prices are in CAD. Note that AliExpress takes a few months to ship to Canada so it’ll be a while before I get the parts.

ProductSupplier/LinkCost
1.3” Inch OLED ModuleAliExpress$3.09
Wemos D1 Mini ProAliExpress$2.25
SHT31 Temperature & HumidityAliExpress$2.62
SGP30 TVOCAliExpress$7.14
JST 1.25 8P ConnectorAliExpress$1.21
SenseAir S8 C02 SensorAliExpress$31.02
PMS 2.5 Air Particle Quantity SensorAliExpress$19.07
AirGradient PCBPCBWay$0
Outdoor EnclosureAmazon.ca$0
Subtotal$67.14 CAD ($49.92 USD)
Shipping to Canada$15.23 CAD
Total$82.37 CAD ($61.24 USD)