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A candle produces roughly the same amount of energy as a resting human

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Re: A candle produces roughly the same amount of energy as a resting human

#71

Post by RGamma »

cjmcqueen wrote: post #45
josefresco wrote: post #2

Text for those who don't do the bird site: A candle produces roughly the same amount of energy as a resting human — 80 to 100 watts, also consuming about the same amount of oxygen and producing the same amount of CO2. In an enclosed area, adding candles is about like adding people from an air quality standpoint.

Almost the exact same thread and thoughts shared on the tweet are here too... Interesting stuff. I wouldn't think Twitter and HN would be so closely aligned.

Turns out the "HN is turning into reddit" jokes only had the platform wrong.

Re: A candle produces roughly the same amount of energy as a resting human

#72

Post by danans »

medstrom wrote: post #51
aqme28 wrote: post #41

Why is a mostly-incorrect* analysis of candles on the frontpage? Just because Carmack is saying it? *: Wattage might be the same, but the effect on air quality is different. Humans don't exhale carbon monoxide and smoke.

It's not incorrect, just misuse of "air quality". In principle it looks like candles and humans could have a very similar effect, because both work by the process of combustion. Humans even supply fat as fuel which is similar to the candle wax. But the details differ so of course different gases could come out as a side effect. Both consume oxygen, which is certainly part of "air quality". But the lesson could've bee…

> It's not incorrect, just misuse of "air quality".

To ignore the the central subject of the comment - air quality - in order to call it "not incorrect" is doing quite a bit of work.

> Seems main takeaway is that one candle = one human, wrt. oxygen in the room. If the numbers are right.

If we can ignore air quality, what is the difference between this and the comparison between 2 60lb dogs and a human in a room? Or any other animals of similar mass that respirate in the same way?

Clearly the comment was an overtly reductive missive targeted at recent concerns about air quality issues created by indoor combustion.

Re: A candle produces roughly the same amount of energy as a resting human

#73

Post by medstrom »

jackmott42 wrote: post #12
h2odragon wrote: post #3

People concern for "air quality" lately has me wondering how in the world humanity survived to this point, in utter ignorance of the horrid damage everything they could smell was doing to them. Perhaps we should be encased in sterile bubbles at birth, with all inputs filtered for purity and consistency. Surely that would be the best way to avoid all the dire consequences of the pollutants surrounding us.

1. there were far less people with far less industry, so a lot of the problems we have didn't exist yet 2. there was, in some regions, lots of living indoors with fires and candles and sleeping with animals, because they had no other choice, and they died in their 30s or 40s at best anyway so it didn't really matter. Probably breathing soot all the time while indoors was part of the reason they died in their 30s and…

Re. point 2: I wish I had sources for this, but as I understand it, few adults have ever died in their 30s and 40s. We hear the average age was 35 in some periods of history, but I don't know how many scientists even said that, maybe it was reporters misunderstanding the point of the number, because to laymen it's a weird way of saying that "child mortality was high and disease was common". Once you were an adult and you didn't catch the plague, you lived to 60+.

Re: A candle produces roughly the same amount of energy as a resting human

#74

Post by HenrikB »

jvm___ wrote: post #48

How bad does our bedroom air quality get? or how much CO2 do two adult humans produce in a 10x10 closed room overnight? Is it enough to push the CO2 high enough to have an effect? I've noticed I sleep better when I sleep separately from my wife. I'm the more violent sleeper, so it's not movement related, so I'm wondering if it's air quality related.

Yes, the amount of CO2 each person produces is noticable, especially in such a small room.

If possible, keeping a bedroom window a bit open makes a noticable difference. Avoid closing bedroom door too.

Similarly, if you work from home, make sure to create a draft once in a while.

We got an Aranet4 CO2/humidity/temperature sensor mostly out of curiosity two months ago. Outdoors it's ~430 ppm CO2. 500-1000 ppm indoors is considered okay (according to the defaults), 1000-1400 ppm high, and >1400 ppm bad.

It's amazing how you don't notice how it slowly creeps up to 900-1000 and beyond. Without the device I would notice, except that I'd slowly get tired. I'd probably also drink more coffee. The device helps you see what's going on and how bad it is. Creating a big draft for 5 minutes clears everything out.

Also, you can definitely see from the historical data when one goes to bed in a ~12 m2 bedroom and then an hour or so later the second person goes to bed. Same if one gets up before the other. Definitely good evidence that keeping a window open is a good thing (if you got clean air outside)

Re: A candle produces roughly the same amount of energy as a resting human

#75

Post by delecti »

Gordonjcp wrote: post #17
delecti wrote: post #14

Earlier quoted context omitted.

> how in the world humanity survived to this point By outbreeding the fact that we also died a bunch for unknown reasons. And I think this tweet is actually a fairly calming view on things. I wouldn't hesitate to share a room with a couple extra people, so I won't worry about a few candles occasionally, because they're a nice benefit to the space. Meanwhile it's an absolute no-brainer (for me and many other people) t…

> Meanwhile it's an absolute no-brainer (for me and many other people) to avoid gas stoves Surely you mean avoiding dangerous electric stoves, which emit hazardous electromagnetic radiation? Edit: Yup, everyone bit. Christ you're a bunch of dafties.

Based on this [1] source, which is clearly biased against electric stoves, an electric heater (lets include a stove in that) "can generate over 100 milliGauss (mG)". The SI equivalent unit is the Tesla, with 1 Tesla being equal to 10,000 Gauss. So that 100 mG from the stove is equal to 10 microTesla. A fridge magnet is about 1 miliTesla [2], so just holding a fridge magnet is 100 times as much "harmful" radiation. It's absurd to think electric stoves are a concern.

[1] https://emfguardtips.com/do-electric-stoves-emit-emf/ [2] https://sciencing.com/strong-standard-magnet-6853786.html

Re: A candle produces roughly the same amount of energy as a resting human

#76

Post by doublerabbit »

recuter wrote: post #66
cjmcqueen wrote: post #45

Earlier quoted context omitted.

Almost the exact same thread and thoughts shared on the tweet are here too... Interesting stuff. I wouldn't think Twitter and HN would be so closely aligned.

I am insulted and feel personally attacked by your reductionist sentiment. We are nothing like those people!

Twitter to HN. HN to SlashDot. SlashDot to Reddit. Reddit to Twitter only to arrive back on HN.

The perpetual internet carousel

Re: A candle produces roughly the same amount of energy as a resting human

#77

Post by blablabla123 »

aqme28 wrote: post #41

Why is a mostly-incorrect* analysis of candles on the frontpage? Just because Carmack is saying it? *: Wattage might be the same, but the effect on air quality is different. Humans don't exhale carbon monoxide and smoke.

Not sure, but I remember the comparison with a light bulb. A bit artificial but it puts unintuitive units in perspective

Re: A candle produces roughly the same amount of energy as a resting human

#78

Post by LazyMans »

amelius wrote: post #43
dekhn wrote: post #4

Earlier quoted context omitted.

except that candles don't just produce CO2, they produce soot and many other molecules which have been clearly associated with negative health outcomes.

This is why I only use hydrogen torches at my dinner table.

I prefer oxygen candles, personally.

Re: A candle produces roughly the same amount of energy as a resting human

#79

Post by implements »

themitigating wrote: post #61
implements wrote: post #59

A bit tangential, but an electric under-blanket on as little as a 10W setting makes a huge improvement to sleep quality in an otherwise chilly bed.

I don't even put the heat on in my apartment after buying an electric blanket. It gets down to 53F but with the blanket only on 3/10 I love it. Another benefit is my head stays cool which I find more comfortable

Ahh. I’ve been pondering creating an enclosed bed [1] - which I believe was common in medieval times.

[1] AKA: https://www.thevintagenews.com/2019/02/25/box-bed/

Re: A candle produces roughly the same amount of energy as a resting human

#80

Post by delecti »

s17n wrote: post #70
delecti wrote: post #14

Earlier quoted context omitted.

> how in the world humanity survived to this point By outbreeding the fact that we also died a bunch for unknown reasons. And I think this tweet is actually a fairly calming view on things. I wouldn't hesitate to share a room with a couple extra people, so I won't worry about a few candles occasionally, because they're a nice benefit to the space. Meanwhile it's an absolute no-brainer (for me and many other people) t…

> We can make gradual incremental change as we learn more though, and we should try to do so. We shouldn't thoughtlessly make gradual changes which sacrifice quality of life for safety (which is the direction that these changes always seem to go) without actually deciding that the benefits are worth the costs.

Agreed, and that was my entire point. I think the tradeoffs for candles are worth it, I don't think the tradeoffs for gas stoves are worth it, and they probably aren't for quite a few people.
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