Good Air Quality

[frognumber]

I found air quality has a big impact on me:

1) Keeping pollutants (especially allergens like pollen) down

2) Keep low CO2 levels

3) Nice temperature

4) Reasonable humidity levels (not too low for health, and although this has not been a problem, not too high for mold).

Those push against each other. Opening windows means ice-cold air in the winter, hot in the summer, and pollen-filled in the spring.

* I have an air purifier in my room, which makes a world of difference.

* I started monitoring PM2.5 and CO2 levels with an AirGradient running ESPHome (which I'm very happy with), Apollo AIR-1 running ESPHome (which I'm happy with), and a set of devices I set up ad hoc with ESPHome (which I'm less happy with). I was surprised at how much of an impact CO2 seems to have on me (or something which correlates with it; who knows?).

* I use a normal window AC in the summer, and radiators in the winter. They don't always keep up on especially hot / cold days.

I thought I'd ask about good ideas of what I ought to do. My general thoughts:

* I could rig up some kind of air filter to suck in air from outdoors. This would reduce CO2 without letting in allergens.

* That would risk mold in the summer, since I'd be pulling in hot air and cooling it. I'd also lose heating / cooling

* I could use an ERV, but those are $$$, huge, and it feels a bit experimental. I'm not quite sure the best way to rig that.

* I could use an HRV (heat exchanger) for some of the benefit, but those are well-known to lead to mold issues.

I just thought I'd open up to discussion.

If anyone knows people who nerd on this (AirGradient and Apollo Automation especially), that'd be an especially good discussion.

[mchannon]

Go low-tech.

Indoor plants can bring your indoor CO2 levels way lower than ambient (which I submit is way healthier than ambient).

Devote 10% of your interior planview space to indoor plants. This used to be commonplace in the 20th century and for some reason just lost popularity.

[mikeodds → mchannon]

Disclaimer: I like indoor plants.

Wouldn’t you need a very large number of indoor plants to bring C02 sub ambient levels with - a human in the room exhaling C02 - compared to just having an open window and cycling the air.

[mchannon → mikeodds]

Let's suggest you're using pineapple plants. They are nowhere near the best choice if CO2 mitigation is your goal.

One human produces 51.4g CO2 per day (note: this number is from the leading source on Google, which is on the low end of a wide range of reported numbers).

100cm2 of leaf area consumes roughly 1g CO2 per day.

So you'd need roughly 5,000 cm2 of pineapple leaf area, or 0.5 m2, or (roughly) 5 square feet of leaf area. Easily doable.

You'd want to triple that to get the numbers noticeably below ambient. Also doable.

During my travels I've measured large buildings that have lots of indoor plants. They feature the lowest CO2 ppm numbers I've ever recorded, anywhere, around 200ppm.

[gnabgib]

Should this be an Ask HN? There isn't a direct question, but perhaps you can form one.

[giantg2 → gnabgib]

Yeah, doesn't seem like an HN question. Maybe better for and HVAC or DIY reddit.

I'd probably look into a minisplit.

[throwaway598]

Well worth AskHN IMHO as it's a worthy discussion.

I enjoy variance. I do get light hayfever, occassionally. But I let the windows open. Let the seasons happen. Enjoy the rain when it rains, and the sun, and the snow. Differences every day stimulate.

[aristofun]

I only wish someone told me earlier in my life that air purifiers do work and do make sense.

I was dumb enough to confure them with compact air humidifiers and discard as snake oil.

[p1esk]

I setup my AC so that it takes in ~20% of fresh air (from outside). This keeps my CO2 levels below 1000 most of the time.

How bad are your CO2 levels?