[HN Gopher] Air conditioning's original purpose was to enable fa...
___________________________________________________________________
Air conditioning's original purpose was to enable factory processes
Author : pross356
Score : 44 points
Date : 2020-06-24 19:52 UTC (3 hours ago)
(HTM) web link (spectrum.ieee.org)
(TXT) w3m dump (spectrum.ieee.org)
| bcatanzaro wrote:
| It's interesting that this article didn't talk about the CO2
| emissions from heating the North. My understanding is that we
| would save emissions if people would move out of Boston and move
| to Houston because heating houses is more carbon intensive than
| cooling them. The temperature differential is a lot bigger when
| heating.
|
| There's something Puritan and not very well considered about
| viewing air conditioning as a new-fangled luxury while viewing
| heating as a necessity.
| saeranv wrote:
| However, it's a lot easier to passively heat a house then to
| passively cool a house. We could easily upgrade building
| envelope standards, incorporate a heat pump, and reduce the
| heating-associated CO2 emissions to a fraction. If we did that,
| I think on net the Houston C02 emissions might be larger, since
| there really aren't equivalent ways to passively cool space.
| post_break wrote:
| A lot of texas power grid is renewable however, which helps
| tilt the scales.
| saeranv wrote:
| This works both ways! You can clean the grid in the the
| Northeast[1], and the clean energy would go a lot further
| to condition your (properly energy-retrofitted) houses then
| a house in Houston.
|
| [1] For example in Toronto, Ontario, the electric grid is
| fueled from hydro (and we get passive cooling from lake
| water). And yet, Toronto's urbanization is so intense (and
| still growing) so the city still needs to reduce the energy
| consumption of it's buildings to manage it's peak power
| consumption. And I would argue this still has a huge impact
| on CO2 emissions given the reduction of transportation
| emissions associated with high density areas.
| lsllc wrote:
| The north east US is the largest heating oil market in the
| world, we consume 85% of the heating oil in the US. Most of
| these oil boilers will be 80% efficient at best. It does get
| quite cold here in the winter!
|
| The answer is building codes that require energy efficient
| construction techniques, and 0% loans for retrofitting existing
| houses with better insulation, windows and heating (actually
| much of this exists via HEAT loans). Tax breaks would help here
| ...
|
| Previously, the only real choices were some sort of fossil
| fuels with natural gas being the most efficient and cheapest
| (although it's only available in urban and most suburban
| areas).
|
| These days, a heat pump is more than capable of both heating
| and cooling even in the depths of a New England winter
| (although you still need a heat source for hot water). However,
| you need the right sized ducting for this which can make it
| cost-prohibitive for a retrofit (but there's no reason why any
| _new_ house should NOT have a heat-pump).
| gruez wrote:
| >but there's no reason why any _new_ house should NOT have a
| heat-pump
|
| Are heatpumps always more economical than gas/oil? I know
| that natural gas almost always beats electrical resistive
| heaters in terms of cost, even though resistive heaters are
| more efficient than natural gas. Heatpumps are supposed to be
| more efficient than resistive heaters, but in areas with
| expensive electricity it still might be more expensive.
| csours wrote:
| >"even though resistive heaters are more efficient than
| natural gas."
|
| You have to be careful about what you measure. Resistive
| heaters are 100% efficient by definition, but you have to
| look at the whole chain. The energy has to be converted
| from X (coal, natural gas, isotopes decay) to electricity
| and transmitted to your home. Only the last step is 100%
| efficient. You lose a lot of energy in generation and
| transmission of electricity.
| cmurphycode wrote:
| I was curious about this a while ago and did some napkin
| math.
|
| Natural gas is roughly $15 for 1 million BTU. There are
| 3412 BTU in a kwhr, so if you heated resistively, you'd
| need 293 kwhr to get 1 million BTU.
|
| In my area, which I feel has pretty high electricity cost,
| we pay $.24 per kwhr, so that'd be $70.
|
| Therefore, you need a 70/15 (4.666) COP for your heat pump
| to match natural gas by price. My understanding is that
| that would be an unusually high number for cold weather
| conditions.
| lsllc wrote:
| The State of NH Office of Strategic Initiatives has a
| nice Fuel Price comparison page that they keep up to date
| (and are adjusted according to cost per MMBTU):
|
| https://www.nh.gov/osi/energy/energy-nh/fuel-
| prices/index.ht...
|
| You can see that as of June 2, measured at $ per MMBTU
| (million BTU): Natural Gas
| $8.31 Oil $17.62 Propane
| $32.93 Wood pellets $21.92 Resistive
| electric $48.84 Air src heat pump $18.74
|
| The fossil fuels are all measured assuming 80% heating
| efficiency, whereas for propane or natural gas you might
| well have a high efficiency unit up to 97% which gains
| you a bit more savings.
|
| These prices may vary depending on location and also I
| think natural gas isn't that common in NH as it's a
| mostly rural state.
| cmurphycode wrote:
| Holy moly. That price per million btu is a lot less than
| the number I stumbled across. Makes it even more obvious.
| mindslight wrote:
| Remember, oil prices cratered over the past few months.
| I'd take the current numbers with a grain of salt.
| lsllc wrote:
| I'm really glad I recently replaced my old 80% efficient
| oil boiler with a 97% efficient natural gas boiler. My
| winter bills are less than half what they were and it
| barely uses any gas during the summer for hot water.
| lsllc wrote:
| A heat pump is only moving heat from one place to another,
| it's not heating "resistively". So your energy cost is to
| run the heat pump, not to "heat" the house.
|
| Having said that a typically, your system is designed for a
| 99% "heating" or "cooling" dry-bulb outside temp from the
| ASHRAE climatic design conditions based on your location.
|
| For example. Boston (Logan Airport) the 99% heating temp is
| 12.3F, so you'd size and design your system for this to get
| your heated space to 70F. There's a secondary heat source
| that fires if the temps drop below this (which happens, the
| 99.6% heating temp for Boston is 7.4F and it often goes
| below 0F). This is often resistive, but could be a hydronic
| coil if you had an on-demand gas combi-boiler for hot
| water. This is also used in an air-source heat pump for de-
| icing the condenser. A ground source heat pump (aka
| geothermal) doesn't have this problem, but requires a well
| to be drilled (100ft per ton of heating/cooling) to provide
| ground water as a heat source.
| baybal2 wrote:
| This is always stunned me how USA manages to spend so much
| more money on heating than Russia.
|
| Then, I learned that USA has near no cogeneration, and
| district heating + detached house living with mostly terrible
| insulation. Most North American apartments are no better,
| with most highrises looking like radiators.
| saas_sam wrote:
| The US generates $65k per capita vs. Russia's $11k. That we
| spend more on heating probably has more to do with having
| more money to spend on heating. I doubt very much that
| Russia's buildings' insulation is much better.
| [deleted]
| kazen44 wrote:
| you would be quite suprised actually. especially in
| cities.
|
| Also, appartment buildings are far easier to heat, not to
| mention a lot of soviet era appartments only have
| communical heating available. Which basically means the
| heating gets turned on in oktober for entire
| city/appartment blocks, Some of those don't even have the
| option to change the temperate/flow.
| zeroonetwothree wrote:
| Some US apartments have shared heating. It's pretty
| annoying because you have no control. I've had to keep my
| windows open in the winter because the heating was set
| too high.
| Lammy wrote:
| I keep my windows cracked in the winter despite having
| control (and payment responsibility, mind) of our
| heating. It's worth being able to think clearly all
| winter:
| https://www.yaleclimateconnections.org/2016/07/indoor-
| co2-du...
| baybal2 wrote:
| Another thing that strikes most Russians when they go
| abroad is how well ventilated the buildings are, and how
| high is the indoor air quality.
|
| In Russia, it's most likely an inverse of venue class.
| Malls, public venues, indoor markets, govt buildings all
| like to save on ventilation.
| harpastum wrote:
| Depending on your climate and what you mean by "windows
| cracked", you would be much better off with a heat
| recovery ventilation (HRV) system. They have the explicit
| purpose of pulling in outside air while only losing about
| 20% of the heat difference between indoor and out.
|
| With slightly open windows, you're losing a bunch of heat
| for very little ventilation.
| bcatanzaro wrote:
| Russians take cold seriously. I lived there for two
| years. Everyone lives in huge apartment buildings which
| have much less surface area to volume ratio than US
| single family homes. And heating is done by big
| centralized plants. It keeps things warm despite the
| weather. Where I lived it would stay below freezing from
| September to April.
| saeranv wrote:
| The effectiviness of heat pumps is insane. I worked in an
| architectural firm, and had an epiphany one day that every
| single one of our highest energy performing projects used
| some sort of (air/ground/water) source heat pump. We had a
| 100% glass building that was better performing then buildings
| designed to PassiveHouse standards because the former
| incorporated a GSHP.
| closeparen wrote:
| Thermodynamics isn't against your quite so much with heating.
| redis_mlc wrote:
| AC was first introduced to US subs in WW2 to make the fire
| control computers more reliable.
|
| Although more comfortable for crew, they lost bunk space for the
| AC equipment.
| 1996 wrote:
| It's funny (and sad too) how in some parts of the world, AC is
| frowned upon: I visited France and Spain, the two sides of the
| border by the Mediterranean had about the same temperatures, but
| AC was a rare oddity in France, while it was very common in
| Spain.
|
| It seemed to be due to beliefs, as the locals said they were
| afraid of getting sick due to AC -- while I don't disagree
| improper maintenance can provide breeding grounds for a bunch of
| microbes, just do the scheduled maintenance and everything will
| be fine!
| f6v wrote:
| It's also that "it's hot only several days in Summer, why do we
| need Acs?" and then year over year Western and Central Europe
| is suffering from "unexpected" heat waves. What makes it worse
| is that residential buildings haven't been built for this kind
| of climate.
| altoidaltoid wrote:
| https://en.wikipedia.org/wiki/2003_European_heat_wave
|
| 14000+ dead in France that year...
| thisisauserid wrote:
| I learned that from James Burke on Connections:
|
| https://www.dailymotion.com/video/x68uf3j
|
| He says it was for treating malaria though.
| hk__2 wrote:
| > It's original purpose was to
|
| Side note: as a non-native speaker I'm always shocked by these
| basic errors made by natives, even more when they're so
| prominent: here it's the very first word of the lead.
|
| Edit: as pointed in the comment the author is not a native. This
| was a general remark.
| smitty1e wrote:
| The extraneous apostrophe is such a common error as to border
| on acceptable usage.
|
| The only people using datum in the singular and data in the
| plural are academics and Latin aficionados.
|
| The fact that the real cost driver was industrial is
| interesting. But improvement of the human condition has been
| ever about the follow-on uses of some new gadget, from fire for
| heat to whoever decided to cook food using the heat from fire.
| gruez wrote:
| > The extraneous apostrophe is such a common error as to
| border on acceptable usage.
|
| And that's sad, especially since it leads to more ambiguity
| in sentences.
| washadjeffmad wrote:
| I couldn't think of an example that would trip up a native
| speaker. What was an example you had in mind?
| chillacy wrote:
| There are so many non-native speakers of english (owing to it
| being the current international language) I don't even bother
| correcting grammar anymore in code comments in pull requests
| anymore. Unless it's like, user facing or something. But
| anyways, all the better I suppose to focus on content.
| vbezhenar wrote:
| Grammar will be fine when browsers and other tools will
| implement good grammar checking. I don't understand why
| browser developers don't focus on it. There are some
| companies like Grammarly solving that issue, but that
| should be standard feature rather than paid opt-in. I can
| translate website in Chrome with a single click, but I
| can't check grammar. And translation is a really hard task,
| while grammar is pretty much formalized and could be coded
| without any AI breakthroughs.
|
| I'm not native speaker and my text likely contains a lot of
| errors. For example I fix spell errors, because browser
| underlines them instantly, I'd fix grammar errors and may
| be I would develop some kind of grammar literacy after some
| time with proper computer assistance.
| chillacy wrote:
| How do you know the author is a native speaker?
| akuma73 wrote:
| What always confused me was that "its" is meant to denote
| possession. For example, I find this to be more consistent.
|
| Bob's purpose vs. It's purpose
|
| For consistency, shouldn't we use: Bobs purpose
| anw wrote:
| Bob, in this case, is a proper noun. It, in the other case,
| is a personal pronoun.
|
| Generally, nouns can go from the nominative (subjective) case
| to the independent genitive (possessive) case by adding an
| apostrophe _. If a word ends in "s", then the apostrophe goes
| after that "s". If the word does not end in "s", then you add
| an apostrophe, followed by an "s" after the end of the word.
|
| A pronoun is treated differently than a proper or common noun
| when being used in its genitive case. Pronouns have
| declension (inflection) that can change their endings so they
| become different words.
|
| For example, we can decline the pronouns to show possession
| using any of these cases:
|
| Accusative (objective) case / Possessive Adjective case /
| Genitive (possessive) case
|
| me / my / mine
|
| you / your / yours
|
| it / its / its
|
| her / her / hers
|
| him / his / his
|
| us / our / ours
|
| them / their / theirs
|
| _Case 1.* "The dog belongs to _"
|
| _Case 2._ "This is _ dog".
|
| _Case 3._ "That dog is _".
|
| In all of these cases, a pronoun does not take an apostrophe,
| unlike you would see with common/proper nouns.
|
| __Note that this can apply to more than just the noun, in
| the case of "The Queen of England's dress", where Queen does
| not take the
| glial wrote:
| I can only remember the rule by remembering that "its",
| "his", and "hers" are pronouns and none have apostrophes.
| brigandish wrote:
| What if their name is "Bobs"? You'd have no way to
| distinguish the name as names are always going to be the
| least consistent part of the language - would you then use
| "Bobss"? But what if their name is "Bobss"...? ;-)
|
| Funnily enough, if their name was Bobs then the possessive
| would be _Bobs '_, but you'll see natives use Bobs's and even
| say "Bobses" (Gollum like) as it's confusing even for us.
| That kind of consistency isn't a strength of the language,
| and the education system is failing too many people (that's a
| whole other discussion).
| dragonwriter wrote:
| > Funnily enough, if their name was Bobs then the
| possessive would be Bobs'
|
| Actually, no; s' is for possessives of plural nouns ending
| in s (well, an s or z _sound_ , which might be an s, x, or
| z, but usually for a plural will be an s, and most plurals
| ending with s won't have it silent, but...); plural nouns
| not ending in s or singular nouns, including those ending
| in s, get 's.
|
| Except for the special rules for classical and Biblical
| names, where then the _number of syllables in the base
| name_ (which then makes the s or z _sound_ rule more
| interesting, because names ending with silent s, x, or z
| are a thing) becomes relevant because English.
|
| https://www.merriam-webster.com/words-at-play/what-
| happens-t...
|
| > as it's confusing even for us.
|
| True, that.
| brigandish wrote:
| There's an article on the front page about Perl 5.7, I'm
| starting to wonder which one has the more difficult
| grammar ;-)
| FabHK wrote:
| Genitive -s works in other languages (eg German) without
| apostrophe and without confusion.
| brigandish wrote:
| How strange that the world does not want to use German as
| its lingua franca then.
| jrockway wrote:
| Many style guides recommend the "Bobs's" form over "Bobs'".
|
| Those style guides also mention many more special cases,
| like "the students' questions" (but "the dutchess's hat",
| because students is plural and dutchess is singular) and
| even break that down to the case where the next word starts
| with s, like "the dutchess' style".
|
| Basically, it is not by any means clear cut.
| dsdklfjskldj wrote:
| The author is not a native speaker.
| https://en.wikipedia.org/wiki/Vaclav_Smil
|
| As a native speaker, it bothers me quite a bit.
| hombre_fatal wrote:
| This is almost always a mistake in muscle memory error than the
| author literally not understanding "its" vs "it's".
|
| It's a typo. The author goes on to use "its" correctly the rest
| of the post.
|
| As a grammar nazi myself, being a typo nazi annoys me. It's as
| useful to the discussion as getting on your case for using the
| U+2019 quotation mark instead of an apostrophe in your
| contraction of "they're" and "it's" in your comment.
| hk__2 wrote:
| > It's as useful to the discussion as getting on your case
| for using the U+2019 quotation mark instead of an apostrophe
| in your contraction of "they're" and "it's" in your comment.
|
| U+2019 _is_ the preferred character to use for apostrophe
| according to the Unicode standard [1][2].
|
| To stay on the point: I agree it's annoying to be annoyed by
| such small, irrelevant details. I wish I could unlearn my
| {grammar,typo}-naziness most of the time.
|
| [1]:
| https://www.fileformat.info/info/unicode/char/2019/index.htm
| [2]: https://en.wikipedia.org/wiki/Apostrophe#Unicode
| not2b wrote:
| I think that the mistake is common because it is triggered by
| a language irregularity. Normally in English, 's indicates a
| possessive. By that logic, something that belongs to "it"
| should be "it's", just as something that belongs to John is
| "John's". But no, we spell the possessive pronoun "its".
|
| And I've often seen autocorrect try to turn a correct "its"
| into an incorrect "it's" or vice versa.
| hombre_fatal wrote:
| Sure, I can see why people mess it up. But unless you see
| someone consistently mess it up (thus, confusion about how
| it works), it's just a typo and not worth derailing
| conversation.
|
| At least grammar nazis can tell themselves that they're
| spreading wisdom.
| acheron wrote:
| There isn't anything irregular about it, pronouns are just
| different from nouns. His, hers, yours, ours, theirs, its.
| jedberg wrote:
| For some reason my computer will underline both it's and
| its with a red line, regardless of context.
|
| On the plus side, it gets me to double check that I did it
| right. But it's still really annoying!
| eatingCake wrote:
| > Normally in English, 's indicates a possessive.
|
| It seems that the opposite is true. ' indicates a
| contraction first, and possibly a possessive iff no such
| contraction exists.
| belltaco wrote:
| "John is" is not contracted to "John's", so it's
| confusing to have "It is" contracted to "It's".
| samatman wrote:
| Fun historical fact: "John's knife" was once a
| contraction of "John his knife".
|
| No longer of course, the latter isn't grammatically
| correct in modern English. But that's where it comes
| from.
| acheron wrote:
| This is not true, it came from an inflectional ending in
| Old English. https://www.merriam-webster.com/words-at-
| play/history-and-us... uses the example "cyning" (king)
| and "cyninges" (king's). In theory the apostrophe stands
| for the missing e.
| Stratoscope wrote:
| > _" John is" is not contracted to "John's"_
|
| John's not sure he agrees.
| nslav wrote:
| I spent a couple summers working at a printer in Massachusetts
| around 2005-2006 and the first year the shop did not have air
| conditioning. The paper came off a large roll at the back of the
| press which was pulled through from the front. Part of the
| process involved sending it through an oven presumably to set the
| ink, then it would go over a chilled roller to cool it off again.
| On particularly hot and humid days it would be difficult to
| restart the press after stopping it as the condensation on the
| chilled rollers would saturate the paper and it would immediately
| rip (referred to as a "tear out") and would then have to be
| manually spliced back together with tape. One night we spent
| something like 10 hours trying to get the press started up again
| after stopping it to change the plates.
|
| Anyway, that's just my story about humidity and printing. The
| second summer I worked there they had installed air conditioning
| and those problems went away. I'm sure they did it for business
| reasons and not because they thought it was cruel to force people
| to regularly work in 100+ fahrenheit temperatures.
| csours wrote:
| I wonder if octovalve/superbottle is coming to home hvac. I spend
| energy to make my water hot for showers and washing. I spend
| energy to make my air cold so I can work without sweating. I
| spend energy to chill my groceries.
|
| I can't help but feel that coordinating those better would lead
| to reduced energy usage (thus reduced cost). I don't know if I
| can feasibly do that right now with residential/consumer tech.
| thebluehawk wrote:
| That's a compelling idea. I've seen systems that use
| essentially solar panels on the roof that heats up a liquid in
| a loop then goes to a heat exchanger which heats up your water
| before it goes to the water heater, thus making it so the water
| heater doesn't have to work as hard.
|
| Could we use the exhaust from your fridge, A/C, furnace, etc.
| to also heat coolant in a similar system that circulates to
| your pre-water heater, thus boosting efficiency. Especially if
| you can dump the exhaust of your fridge outside rather than
| paying to heat up that air, then cool in down again with your
| A/C.
|
| The question is if the cost savings would be worth the cost of
| the system.
| csours wrote:
| > The question is if the cost savings would be worth the cost
| of the system.
|
| I think it might be, if it was built into the home from the
| beginning, and the engineering cost was spread out over a
| large number of units. In other words, I don't expect it to
| make sense for one homeowner to retrofit their house.
|
| It would make more sense in a condo/apartment/multi-
| unit/commercial situation.
| extrapickles wrote:
| There would be decreased costs for the entire house as you then
| no longer need a heat pump in you fridge, water heater, etc if
| you tried to emulate current hot/cold use. If I designed the
| system, it would just be a hot and a cold loop that goes
| throughout the building, with a standard outlet that had both
| the hot and cold lines present.
|
| For residential, you could install faucets that had a internal
| heat exchanger that would let you have actually cold or hot
| water for cheaper than a traditional on-demand water heater.
| HVAC would be better as individual control of the heat for each
| room wouldn't add much extra cost, so your south facing rooms
| can get more cooling without having to freeze everyone in the
| other rooms.
|
| For restaurants, the system would be particularly attractive as
| they can have heated/chilled food holding (and work surfaces)
| and they would be able to be swapped between the two by
| flicking a switch, so the winter menu (or the lunch menu even)
| could feature more hot items, and the summer (or dinner) menu
| more cold things without wasting capital (and space) on
| equipment that isn't used all the time.
| airstrike wrote:
| Sounds very interesting! I'd love to learn more if others could
| chime in
| lotsofpulp wrote:
| A version of it is a heat pump water heater:
|
| https://www.energy.gov/energysaver/water-heating/heat-
| pump-w...
|
| In my home, we leave the garage door open when it's warm so
| the cold air that the heat pump water heater expels can come
| into the house.
|
| It's basically an air conditioner that dumps heat into the
| water, instead of the outside air.
| blakesterz wrote:
| Funny, being from Buffalo I've always heard it was invented here,
| and I read this and it says... Brooklyn?!
|
| In 1902 the factory's operators asked Willis Haviland Carrier
| (1876-1950)... I guess he's FROM Buffalo, but created it FOR the
| place in Brooklyn. Good to know the details of this little trivia
| piece now.
|
| https://www.bizjournals.com/buffalo/blog/the_last_laugh/2011...
| elicash wrote:
| Florida also claims credit because of John Gorrie.
|
| In fact, in Congress each state contributes two statues to the
| National Statuary Hall Collection. One of Florida's is of John
| Gorrie -- that's how much state pride is taken in it.
|
| https://www.floridainvents.org/john-gorrie/
| MattGaiser wrote:
| Yet another misery conquered by technology.
| AceJohnny2 wrote:
| Evil, unholy technology!!!1
|
| https://en.wikipedia.org/wiki/Cool_Air
| hetspookjee wrote:
| What a splendid read! Thanks for the link. Here's the
| original short story:
|
| https://www.hplovecraft.com/writings/texts/fiction/ca.aspx
| AceJohnny2 wrote:
| > Characters: Doctor Munoz: A Spanish physician of _"
| striking intelligence and superior blood and breeding"_
|
| I can't believe I glossed over how racist Lovecraft was when
| I read this in my teens.
| sand500 wrote:
| 99% invisible podcast about AC
|
| https://99percentinvisible.org/episode/thermal-delight/
| AnotherGoodName wrote:
| A much better article since it discusses home design. You
| really can live comfortably without AC in even harsh
| environments. In particular houses with basements that have
| airflow through to the rest of the house. Underground the earth
| is ~55F the world over and it's really not difficult to design
| houses to make use of this fact.
| post_break wrote:
| All of that is dependent on location. If I dig a basement I'm
| under water.
| chaz wrote:
| I toured the main FedEx hub in Memphis several years ago. They
| have many buildings that sort packages on high-speed machinery.
|
| In one building, there was a long line of parcel trays, each
| carrying a single item. The trays would move fast down the line
| and, at just the right moment, tip the parcel out and into a bin
| below, each for a different flight. Because of the tray's speed
| (and the trays don't stop), the tipping needed to start well
| before it was over the bin, at a precisely calibrated time. A
| video of these machines is here, at 1m 45s:
| https://youtu.be/xytmh6t3Grk?t=105
|
| It was one of the few sorting buildings that was air conditioned
| in the hot Memphis summers, and not for the humans. The humidity
| affected how quickly the parcels slipped off of the tray, and
| they might end up in the wrong bin.
| nimbius wrote:
| Anecdotal evidence but my ex boyfriend was an HVAC technician and
| frequently serviced suburban households. He was always stunned at
| how cold most customers wanted their homes in the summer. "theyre
| like chubby little eskimos in front of the TV" he used to
| chuckle, and most would ardently refuse energy saving ideas like
| acclimating to 75 degrees in the home, installing ceiling fans,
| or opening windows instead of running the HVAC system. Most
| people would just run the system constantly until the blower died
| or the compressor burned up every six or seven years.
|
| Summertime is supposed to get a little warm :).
| Grakel wrote:
| I would like to politely disagree; I think the point of having
| control of the temperature in your house is to have it be
| exactly the way you want it all the time. Now, it may take a
| while for the technology to catch up to that, but I think
| people would happily install a new system every few years,
| rather than lose that control. I personally like it cool enough
| to wear layers, regardless of what month it is.
| maerF0x0 wrote:
| The issue is that many people do not realize the range to
| which they can acclimatize. And the acclimatization has
| varying degrees of value depending on the temperature
| differential to outdoors.
|
| Eg: in Canada one can keep their home a few degrees cooler in
| the winter to save quite a bit of money. Same idea in hotter
| climates -- keeping it 75 instead of 70 is something one can
| acclimatize to, but has more value when the out door
| temperature is 100f vs 80f.
|
| Overall I think it's just momentum. When I had a nest I used
| the dynamic range that said only cool if my place is over 78
| and only heat if it's 68. Everything else, just roll with the
| ambient.
| londons_explore wrote:
| > The issue is that many people do not realize the range to
| which they can acclimatize.
|
| Said acclimatization normally comes with downsides... When
| its hot, one might be less productive, feel less motivated
| to get stuff done, etc. It's pretty hard to measure that
| cost on a personal basis.
| ksdale wrote:
| If you feel worse enough to be less productive, have you
| actually acclimatized?
|
| I grew up in a house with air conditioning on all the
| time during the summer and thought that there was no way
| I could ever handle indoor temperatures of, say, 75. Then
| I spent a couple years in Arizona and wanted to save on
| AC costs in the summer, it took a while to get used to,
| but now an indoor temperature of 70 in the summer feels
| very cold to me.
| jdofaz wrote:
| As a kid in Phoenix my parents forbid setting the
| thermostat below 80, unless the humidity outside was low
| enough we could use the swamp cooler instead of the air
| conditioner.
|
| Now I'm comfortable at 78 with a ceiling fan, to me 75 is
| cold and 70 would be freezing
| mamon wrote:
| But what is the point of cooling your apartment to 65
| Fahrenheit, when there's 90 degrees outside? In summer you
| would still wear shorts and t-shirt when inside, not
| sweatpants and hoodie, right? Setting AC to 75 degrees
| instead would be much more reasonable.
| cgriswald wrote:
| I wear shorts and t-shirt in sub-50 degree weather. 75
| degrees is uncomfortable, even if I'm sitting doing
| nothing. Forget about doing things around the house at that
| temperature. At a certain point, I'd rather not even have
| AC at all than spend money to make it marginally more
| comfortable. (I also have huskies who don't like 75 degrees
| all that much.) On the flip side, I'm more than comfortable
| having the house be 55 degrees in the winter.
| balfirevic wrote:
| This is why it makes no sense to question how cold or
| warm other people like their home. I'm probably most
| comfortable around 25 degrees C (except perhaps when I'm
| exercising) - this is both during the summer and during
| the winter (and also during the day and night).
| adrianmonk wrote:
| One difference, and part of the appeal, is how quickly you
| cool off after being outside for a long time.
|
| Let's say it's 100degF, and you're outdoors for 2 hours.
| You feel lethargic and sapped of energy, and you look
| forward to going inside. When you finally do, you get a
| gigantic cold beverage, take off your shoes, plop down on
| the couch, and wait to feel normal again. It might take 30
| minutes before you start to get there.
|
| If it's 65degF inside, this process happens faster than if
| it's 75degF.
|
| No doubt, the moment you get inside, you already feel
| better whether it's 65degF or 75degF because neither one is
| 100degF. But if you're alternating between inside and
| outside a lot, colder is still preferable.
| jschwartzi wrote:
| Actually I find that if I'm acclimated to 90-degree
| temperatures it doesn't take very long for me to cool
| down in 75-degree temperatures at all. That's how
| acclimatization works, after all. You get used to the
| temperature and your body doesn't perceive it as hot or
| cold anymore.
| fizixer wrote:
| I moved to a new apartment and noticed my roommates would turn
| the main floor into a freezer (I live on second floor). I
| noticed thermostat levels as low as 50 F.
|
| A few days later the HVAC stopped working and what do we know,
| it's because of of ice buildup.
|
| The other thing, the vent-ways are designed so my room on
| second floor has a floor-vent. This works for heating but not
| for cooling. The cool air that comes out of the vent stays in
| the region between the floor level and roughly 1 foot above it.
| So my feet are fine, but I'm otherwise feeling hot.
|
| It's a straightforward solution that cooling-vent should be in
| the ceiling and heating vent on the floor. But it costs more to
| have this kind of installation that's why most landlords/home-
| owners don't go for it? I don't know.
| cgriswald wrote:
| A fan blowing the cool air up (or a ceiling fan running
| "backwards") is the solution to that problem and a lot
| cheaper than running extra ductwork and controls to divert
| air inside the walls.
| lsllc wrote:
| Sounds like it might be low on coolant, you might want to get
| it serviced.
| amluto wrote:
| There's a possible explanation: humidity. The temperature that
| people find comfortable depends on humidity, and most AC
| systems have little or no ability to independently control
| temperature and humidity. Designing a system to achieve, say,
| 75F at 50% RH in a given climate for most of the summer is a
| black art, and most systems fail. So you can get 75F and feel
| sticky or you can get 65F and feel okay if slightly chilly.
|
| A lot of builders in humid climates will install AC _and_
| central dehumidification, which can work better. In theory, one
| can tweak the indoor heat exchanger temperature to change the
| sensible vs latent cooling ratio, and there is at least one
| obscure heat pump vendor that claims to do this on the fly. I
| don't know how well it works in practice.
| gruez wrote:
| > He was always stunned at how cold most customers wanted their
| homes in the summer. "theyre like chubby little eskimos in
| front of the TV" he used to chuckle, and most would ardently
| refuse energy saving ideas like acclimating to 75 degrees in
| the home
|
| Or maybe they like cooler temperatures. Kind of like how
| sometimes you see someone outside wearing a tshirt + shorts
| when the weather's only 50-60f. It's only absurd if they've set
| the temperature low AND they're shivering or wearing a
| jacket/sweater/blanket.
| renewiltord wrote:
| I wonder if there's a correlation between population BMI and
| a propensity to wear non-insulating clothing. Of course the
| natural correlation would be body fat % but I wonder if it
| shows up in large population metrics like BMI. Certainly with
| a 40% obesity rate, we could see a large number of people
| claiming they 'run hot' when they're really just obese.
| nradov wrote:
| Air conditioning probably makes some people slightly
| fatter. There is a metabolic cost to regulating body
| temperature. As the temperature rises you actually burn
| more calories on thermoregulation.
|
| https://abcnews.go.com/Health/Diet/story?id=2120381&page=1
| goda90 wrote:
| Funnily enough, my thermostat had some bug last night and kept
| the air conditioner on all night long. It's usually set to 72F
| and it got down to 58F(while outside hit a low of 60). I got it
| to turn off, but since it's relatively cool and partly cloudy
| today, my house has taken all day to get to 66 and now I'm
| acclimatizing to it.
| jdofaz wrote:
| wow, you're lucky your a/c didn't freeze up
| chills wrote:
| Meanwhile in NYC: my apartment is regularly heated to 85
| degrees in the winter, and it's commonplace to open the window
| and let in some freezing air to fight the radiator.
| cfallin wrote:
| This is apparently an artifact of the 1918 flu pandemic:
| building architects / heating engineers intended for windows
| to be kept open to ventilate spaces in the winter, and so
| steam heating systems were over-provisioned. A number of
| friends in old apartments in Pittsburgh had the same issue
| with building heat.
|
| (Relatedly, I wonder what effect the current pandemic will
| have on the modern trend of well-sealed homes...)
| causality0 wrote:
| The headline is not strictly accurate. Putting aside non-
| mechanical indoor climate conditioning that dates back thousands
| of years, in 1842 John Gorrie used an evaporative cooling machine
| to create cold air for hospital patients. Carrier was just the
| first to use an electrically-driven compressor.
| hinkley wrote:
| It's odd to me how both this history and the one on Wikipedia
| seem to keep industrial refrigeration and industrial air
| conditioning at arm's length, as if air conditioning isn't a
| walk-in cooler scaled up to building size.
|
| 30 years before Carrier, Carl von Linde was refrigerating beer
| for Spaten Breweries and within 10 years everybody was doing it.
| It seems like the key difference is that his chiller was
| indirect, freezing water instead of chilling air.
|
| I think I first heard of this on Connections 3, which of course
| makes these connections because that's what they do.
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