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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

#141

Post by qlm »

HenrikB wrote: post #74
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…

I've never been sure how to reconcile this with advice about insulation.

It's currently really cold where I live, and I am trying to limit outside air coming in as much as possible. This then leads to the air having uncomfortably high levels of CO2, as confirmed using an air quality sensor.

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

#142

Post by tofof »

anonymouskimmer wrote: post #134
LazyMans wrote: post #78

Earlier quoted context omitted.

I prefer oxygen candles, personally.

My dad was on submarines and talked about these. Do they also provide light, and if so what color and intensity?

They burn at 600C (1100F) so I don't think you'd want to view the reaction directly; usually they have to be deliberately contained to contain the heat to sustain the reaction.

https://youtu.be/g3Ud6mHdhlQ?t=738 (linked to correct timestamp) shows the remains of a burned one and loading fresh ones on a submarine.

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

#143

Post by red-iron-pine »

singularity2001 wrote: post #97
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.

"they produce soot and many other molecules" welcome to my family Also s/produce/release/g

Underrated response. Not only a subtle fart joke but also pedantic about words.

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

#144

Post by tnorthcutt »

rsynnott wrote: post #105
dsfyu404ed wrote: post #13

Earlier quoted context omitted.

The chemical alternatives don't exactly give me confidence (though who really knows what's in a modern candle?). At least candles are a known-known even if non-optimal.

I mean, cooking with wood fires is a known-known and we've been doing it forever... but it's the biggest cause of death by air pollution.

Even bigger than pollution from e.g. burning coal/oil/etc.?

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

#145

Post by anemoknee »

anonymouskimmer wrote: post #134
LazyMans wrote: post #78

Earlier quoted context omitted.

I prefer oxygen candles, personally.

My dad was on submarines and talked about these. Do they also provide light, and if so what color and intensity?

Depends on what state the oxygen is in and any other friends who may react/combust with.

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

#146

Post by tuatoru »

patwolf wrote: post #131

I live in a newer house which is air sealed to improve energy efficiency. With all the talk of indoor pollutants like CO2 and NOx, I often wonder if the air quality is worse than it would be in an older, drafty house. When I research it, most of the results on google are from companies that perform sealing, making it difficult to get unbiased answers.

Install an energy recovery ventilation system[1] [2]. If you have the money.

1. https://en.wikipedia.org/wiki/Energy_recovery_ventilation

2. Schematic picture: https://www.panasonic.com/nz/hvac/products/energy-recovery-v...

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

#147

Post by nicholsonpk »

CamperBob2 wrote: post #136
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.

He's off by at least an order of magnitude. Otherwise, lighting 10 candles would be like firing up a 1000-watt space heater, which is obviously not the case.

Or the space heater is more efficient because it's not producing light.

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

#148

Post by Atheros »

qlm wrote: post #141
HenrikB wrote: post #74

Earlier quoted context omitted.

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…

I've never been sure how to reconcile this with advice about insulation. It's currently really cold where I live, and I am trying to limit outside air coming in as much as possible. This then leads to the air having uncomfortably high levels of CO2, as confirmed using an air quality sensor.

It can't be reconciled. Which is why there are going to be more posts about air exchangers on HN in the future.

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

#149

Post by danans »

tristor wrote: post #139
danans wrote: post #128

Earlier quoted context omitted.

> It doesn't matter if you use induction, radiant, or coil electric, they all produce just as much cooking fumes as gas, and the gas burning has a negligible impact. > I've confirmed this myself many times over with calibrated sensors. This really means nothing considering that rigorous studies and metastudies [1] have been performed and the results published that demonstrate the opposite: that gas stoves result in C…

> Most range hoods in single family homes are externally vented, I wish this were true, unfortunately it's not. Most homes in the US, including freestanding SFHs, use recirculating range hoods. > that gas stoves result in CO and other harmful emissions that electric stoves don't, independent of what is being cooked. This is true. It's also a negligible difference, and mostly immaterial if you are externally venting f…

> I wish this were true, unfortunately it's not. Most homes in the US, including freestanding SFHs, use recirculating range hoods.

We must have very different anecdotal sample populations of single family homes, because I've only ever seen the recirculating types in condos and apartments, where they are done that way due to space/ducting constraints. But there is very little data available on this question. The closest I found was in this study relating specifically to California:

"A survey-based study of 1448 detached houses built in 2003 reported that 80% had range hoods exhausting to outdoors and 4% had downdraft ventilators, while 13% had recirculating range hoods and 3% had no range hood or did not know [34]"

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7729668/

Those stats echo my own observations in two places: California and the Midwest. But it's possible that it's completely reversed in other places. Building codes can vary a lot, after all.

I completely believe that recirculating fans are more prevalent in low-income resident properties, though. That's also something I've seen extensively.

> Externally vented range hoods are both quieter and are actually effective, and train people to use them once they're exposed to them.

People are really bad at diligently doing inconvenient things, even if it means an improvement in their health. My dentist is always on my case about flossing more, but I end up starting up a week or two before my cleaning. Also, we are bad at evaluating invisible or quotidian risks, which is why many have an incorrect understanding of the risks of flying vs driving.

The long term solution to this problem is to require automatic makeup air ventilation systems for all kitchens in the codes, but that will probably be a long pull. As for indoor gas stoves, I imagine with time they will have the same trajectory as ICE cars. Remember that gas stoves were once the novel high tech replacement for wood and coal stoves, and also on the basis of the improved health and convenience, just as induction is today.

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

#150

Post by CyberDildonics »

Gordonjcp wrote: post #103
fastball wrote: post #30

Earlier quoted context omitted.

Is non-ionizing radiation hazardous?

Put your hand on the cooker ring and tell me.

You understand that if things touch each other the heat transfer isn't from radiation right?
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