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Air conditioning's original purpose was to enable factory processes (ieee.org)
111 points by pross356 8 days ago | hide | past | web | favorite | 200 comments





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.


In a previous life I worked for a company that made extremely precise tooling for airplane manufacturing. These things were often upwards of 200ft long and 60ft tall. And they are so precise, that a difference of 5F could make the steel structures grow enough to be out of spec. Most aerospace factories have tightly controlled HVAC for this reason. Well, anyway, we installed a set of tooling in a factory in Japan where the summers can be quite hot. They didn't have HVAC in the factory and this resulted in a 30F gradient from bottom to top. This meant that we had to redesign some connections between parts to progressively account for thermal expansion. This crazy problem would not have existed had they just had HVAC!

Yeah no, it really depends on the working piece (geometry), material, manufacturing and so on...its incredible complex, some milling machines work 24/7 (even without a piece in it) just to uphold the overall machine temperature. A HVAC could make stuff even worse when your piece or machine comes in to the cold flow.

Do you think it would have been cheaper in the long term, e.g. 10-20 years, for them to install & run the HVAC continuously? Was the redesign terribly difficult & expensive?

It's been a decade so my memory is fuzzy, but it was likely on the order of $1-3million (USD) and 3-6 months. Not sure what HVAC would cost over that time.

The real problem is that these types of adaptations are only in spec over some range. Any deviation from that range can be problematic and non-linear.


wouldn't it be cheaper to buy a few dozen box fans from the local electronics store?

Circulation is not cooling.

Technically, parent says the issues was the temperature gradient, so this may have helped?

Normally, high precision measuring rooms have zero airflow, otherwise have a constant temperature in the room and on the piece is not possible.

Sorry, could you clarify? It seems like zero airflow would inhibit a constant temperature?

For example you putt those pieces like 24 hours (depends on thickness) before measuring in that room, the piece should have from it's core to the edges the same temperature.

Airflow inhibits a precise measurement, imagine you putt something in that room that changes the airflow just a bit, so more warm air from the ceiling hit's one side of the piece.

Always when you try to measure something, no outer energies should interfere (no temperature change and no force like airflow or even driving cars outside of the building), it could even be, that the airflow creates vibrations in the piece, like rolling cars do.


The issue is that the temperature in the room is non-uniform. The ceiling is 20 degrees hotter than the ground so over time the object will have the same distribution.

without HVAC wouldn't the temperature already change drastically throughout the day due to weather?


You'd need much more serious fans. And this method lacks any kind of real control. It would reduce the gradient though.

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.


Was wondering why the video quality looked like shit until I realized that it's a "virtual reality video"

I was wondering why a simple youtube video was making my CPU fans kick into overdrive, then I realized the same thing.

It's just mapping a rectangle to a sphere. I wonder what's wasting the CPU.

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.


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).


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.

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.


My very first apartment in Boston was on the fourth floor of an old building and management controlled (and paid for) the heat. The building was so inefficient that in order to heat the lower floors to a temperature just barely above freezing my unit would regularly be 85 degrees or more with the windows wide open.

I’ll never forget my first big winter storm thinking I was going to die of heat stroke because I had to shut the windows to keep the snow from blowing in. Some people on my floor would leave their window unit air conditioners in year-round to counteract the heat.

It was so wasteful and almost no one in the building had a comfortable temperature in their apartment all because it was cheaper/easier for management to just keep burning a ton of oil instead of investing in a bit of insulation.


A lot of the winter overheating comes from poorly insulated pipes, unmaintained steam valves, and broken radiator controls. I lived in Boston for a few years and had the same issue in my first spot - old apartment complex, big boiler in the basement, and way too hot in the winter.

Afterwards, I moved to a nicer but even older building where the landlord had bothered to retrofit a modern boiler with separate heating zones for the different apartments. Crucially, the radiators had new control valves the lines had modern insulation. It was like night and day. I think the retrofit cost over $10k, so like you said, the path of least resistance is often crappy heat.


This. There was a great video posted on HN a couple years ago, by one of the few guys around who tunes up these old radiator systems. Apparently a lot of them were quite genius in design, but years of neglect make them not work very well. Was a fascinating video to hear him talk about common problems, and the amount of troubleshooting and problem solving involved with making these radiator systems work as designed again.

Dan Holohan, for those interested. https://news.ycombinator.com/item?id=18430512


What a cool video and thread! Thanks for sharing! Sometimes I wish HN had a “random old thread” button like Wikipedia so people could stumble upon the hidden discussion gems like this one.

>It was so wasteful and almost no one in the building had a comfortable temperature in their apartment all because it was cheaper/easier for management to just keep burning a ton of oil instead of investing in a bit of insulation.

Making old housing stock efficient at scale is fundamentally incompatible with the laws in MA (local as well as state) that make it possible to both make incremental improvements as budget allows and be on the right side of the law.

People suffer through expensive old utility systems because they can't do X without hiring a licenses pro who can't do Y without pulling a permit and the town won't grant a permit for Y unless Z that has to be touched do do Y is brought up to modern code at the same time which would be fundamentally incompatible (usually for cost reasons) with the goal of the work.

Incremental improvement is more or less disallowed by law or at least massively dis-incentivized. You either have the cash to completely renovate a building and put all new everything in or you do nothing.


That’s true, and I’ve suffered from the same problem when I later bought a home in Southie built in the 1870s. Just replacing the water heater was thousands of dollars.

In the case of my first apartment though I know for a fact my landlord had more than enough cash to update the building if she wanted to - her husband owns the Red Sox.


Should have connected the hot side of your ac to the first floor lol.

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.

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.

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.


Also something interesting to note about Russia is hot water is provided by the municipality and not through a hot water tank in your own apartment like in North America. This would certainly reduce heating costs per person by offsetting them to the state.

> This would certainly reduce heating costs per person by offsetting them to the state.

Unless municipal hot water is somehow much more efficient than hot water heaters (and I'm skeptical, given the heat lost in transit), then it doesn't offset the costs per person, because those costs still have to be paid.


The main reason it can be more efficient is that they use waste heat from power plants.

In principle you can do the same thing at a smaller scale. Instead of burning natural gas or diesel/home heating oil in a furnace, burn it in a generator and heat your house with the engine coolant.


Correct. Here for example you can see a pipeline running superheated water at ~120 C (250 F) 8 miles from the fourth-largest coal power plant in the world (5 GW) to a medium size city:

https://goo.gl/maps/VmaFQrrX5VvRKFdu6

The plant generates so much waste heat (around 10 GW) while generating electricity that the heat loss in transport is pretty much irrelevant, as the heat is free anyway from the power plant's point of view.


You can use heat from burning garbage as well. My town has an incinerator which burns garbage at high temperatures, the heat is used to warm water which is used to heat buildings (as far as I know not as hot water directly).

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.

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...

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.


Unfortunately I don't own the building but thanks for the info about HRVs

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.


'Shared heating' needn't mean no control over the heating.

Many buildings in Denmark are supplied with heat (for room heating and hot water) by a municipal system, but each house or apartment can adjust the temperature of the room heating, with radiator valves or electronic thermostats.

We're charged based on how much heat we extract from the system.


a hundred years ago they thought fresh air was an important part of staying healthy, so building heating systems (those big cast iron radiators) were designed to heat effectively in winter with the windows open.

I lived in the Southern California mountains. For those who are unaware, yes, that means snow. Winter temps down to the low 20s(f). In summer, it seldom got over 90s. It was the house I grew up in, and I purchased it from my dad. Because it was an FHA loan, we had to have a heating/cooling unit installed, so we had a heat pump added.

Aside from being absolutely hideous, the unit was utter shit. The "heat" was mostly cold air in winter. The pump would turn on, and ducts' air was cold (being outside and all), cooling off the house MORE when it was already freezing. Eventually some lukewarm air would come in until the unit got too hot and would turn off, again pushing colder air back into the house. And in summer, the cool air was nowhere sufficient to cool the house. Your only bet would be to keep it on all day with all drapes closed, lights off, do not cook, and don't move around too much.

To contrast this, we generally used a wood stove to heat the house. A few logs would keep the house nearly uncomfortably warm for hours. In the summer, we ran an evaporative/swamp cooler. As long as there were no thunderstorms, the house was very pleasant. I cannot be convinced that heat pumps are the way to go.


It sounds like you had some kind of compliance system that was low-quality or not big enough for your needs. Heat pumps and air conditioners are the same technology, you just make the hot side the inside instead of the outside. They're how your freezer works, but in reverse.

Their main limitation is that they aren't effective in extreme cold. To pump heat there needs to be some to begin with. But most populated areas don't get that cold too often and they can be backed up by resistive heaters for the couple of nights a year when it is.


> Their main limitation is that they aren't effective in extreme cold.

I've researched this a lot since I want to install one and live in a cold climate. The new ones can put out a lot of heat at low temperatures.

As an example, see the linked "AHRI Certificate" for the product below. It states:

- 11,800 BTU/h at 47 degrees fahrenheit

- 7,800 BTU/h at 17 degrees fahrenheit

I feel like I've even seen some that say they put out 100% of the rated heat at like 5 degrees fahrenheit.

You have to make sure you get a cold weather one, with a base pan heater. They're usually more expensive.

Here's one I've looked at for reference. It costs $300 more than the less extreme temperatures one. I don't think it comes with a base pan heater, but I'm not sure: https://senville.com/12000-btu-mini-split-air-conditioner-se...


I have a friend who just installed a modern air source heat pump in a new build in Mass at the end of last year and he's pretty happy with it so far. The tech has improved significantly in recent years -- up until recently, they were not recommended north of DELMARVA.

>These days, a heat pump is more than capable of both heating and cooling even in the depths of a New England winter

Are you talking about air source or ground source? And by "the depths of a New England winter" do you mean temperatures below 50 F?

I lived in an apartment for a while that had some sort of heat pump, but there was a switch for "emergency" (i.e. resistive) heat that was necessary for any warmth in the winter.


Your heat pump had something wrong with it. Quite possibly it wasn't going into defrost mode or wasn't able to actually finish defrosting by the end of a cycle. The way that's intended to work is that after running for a bit when the ice starts blocking air flow and insulating the coils on the outdoor unit it'll switch to cooling mode and turn on resistive heating. That quickly thaws out the coils and then it switches back to heating and turns off the resistive heating inside. I find it odd that you even had to manually turn on emergency heat to get any heating out of it. Normally if the thermostat is too far below the setpoint it'll automatically start using resistive heating as well (most thermostats will indicate "aux heat" when that happens). Maybe your thermostat didn't? Or it did and the reversing valve was stuck so it was just stuck in cool mode 100% of the time.

Modern air source heat pumps can be effective down to -25C (-13F) in heat pump mode, and will automatically switch to resistance heating if needed.

I'm building a house where it can get to -35C at times (but usually above -20C in winter) and we will have an air source heat pump for hot water, heating and cooling [0]. Combined with good insulation and 10kW of solar on the roof, we should generate more electricity than we use over the year, and no need to burn any fossil fuels.

My wife has insisted we have a wood burning stove for atmosphere, so that will function as a backup heat source if needed, but most likely it will generate too much heat to be used regularly.

[0] https://www.daikin.eu/en_us/product-group/air-to-water-heat-...


I tend to take a dim view of the phrase "can be" because it's so weak. It's logically equivalent to "may not be" and is entirely consistent with "essentially never is".

But sure, the heat pump in your future home may well be much better than whatever they were doing decades ago. I don't know if my apartment used ground heat, but I doubt it.


I meant "can be" in that if you buy one rated for those temperatures it will reach that, but not all heat pumps are rated for that.

It would be ground source, and a day of 50°F would feel like shorts and sandals weather that time of the year.

You don't have to tell me. I was looking for sources of misunderstanding. In a multifamily structure, at 50 F, in my experience, heat through shared walls probably keeps you reasonably warm without any heat of your own.

>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.


>"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.


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.


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.


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.


Holy moly. That price per million btu is a lot less than the number I stumbled across. Makes it even more obvious.

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.

With 80% efficiency, you have to burn 1/0.8=1.25 units of fuel to get one fuel unit worth of useful heat. With 97% efficiency it's 1/.97≈1.03 units.

So if fuel prices and the amount of useful heat usage stayed the same, then your bill should be 1.03/1.25≈82% of what it was before. If your bill is "less than half" then something else must have changed.


He switched from burning oil to burning natural gas. According to the table, gas is way cheaper.

Yes, I switched from an oil burner (#2 heating oil) to a high efficiency natural gas boiler. The other key ingredient is that the oil boiler was 20 years old and did not have "cold start" (so it always keeps itself at temp even in the summer).

Any modern boiler (gas or oil) will almost certainly be cold start, so it only fires when there's a call for heat. This alone probably saves a gallon of oil a day at least.


There's a reason the Energy Saving Trust over here in the UK discourages people from replacing their gas boilers with heat pumps thinking it'll save them money, even though our climate is more suited to it than the colder parts of North America. Unfortunately, that doesn't stop our press pushing the idea we should go for heat pumps because Germany has. (They don't have such widespread natural gas connections to homes as the UK and so are reliant on oil-fired home heating, which as you can see has very different economics.)

Remember, oil prices cratered over the past few months. I'd take the current numbers with a grain of salt.

We also don't know what the long-term fallout is going to be. Natural gas has been unusually cheap recently because it's a byproduct of fracking for oil. But low demand for oil means less demand for fracking which mean less natural gas production.

It's really hard to predict where prices are going to be in a year, because you really have to predict how well the oil industry can predict future demand in this environment. If they shut down too much production and then demand comes back there could be a price spike. If they expect a quick recovery and are wrong, prices could remain on the floor for a good while.


This is also the "off" season for heating oil, so it's usually cheaper.

According to the NH page, that price was June 2. For the Commonwealth of MA, as of late May it was $2.07 on average and it's down 33% on last year:

https://www.mass.gov/service-details/massachusetts-retail-he...

You can see it has dropped from $3.04 on Jan 7 2020.


Austin, TX area:

We used to live in 1800sqft house built in 1992 in the affordable neighborhood (so fiberglass bats in 4x2 walls). Gas heater, electric cooling. Gas water heater. Gas stove (we don't cook much, so this one probably doesn't have significant effect). We regularly got a bill over $250 in the summer for electricity + gas. Sometimes over $300. In the winter combined bill would be around $150. In summer second floor was never comfortable (part of it was poor circulation I am sure, but part of it was HVAC not cooling well enough)

We also just finished new 3100sqft house. The new place doesn't have natural gas, so we decided to go all-electric - water heater, HVAC, cooktop/ovens, and new addition - pool-heater. Our electric bill now fluctuates between $200 - $280 year around. All appliances, including water heater, are heat pumps. Extra bonus - garage, where the water heater is located, is cool during summer. Both water heater and HVAC has resistive heating elements for very cold days (we get enough of these to matter).

I am sure I can get average bill lower a bit if I tweak pool water and heat pumps schedule.

The house has open cell foam installed around the envelope (so the attic is alright to be in even during the hottest days) and we have forced ventilation (since the house is sealed essentially).

The water heater (80 gal) I bought myself and it was $900 on ebay. Similar product bought at Home Depot would cost probably $1,200 - $1,400. A bit more than natural gas heater, but not prohibitively so. HVAC installation (2.0 and 2.5 tons units) was under $20k for the whole house. Not sure how much traditional gas+electric non-heat-pump install would be, but I don't think it would be significantly cheaper.

So yeah, at least for southern places, heat-pumps appears to make a big difference.


In the UK they want to move as many people as possible onto heatpumps, away from natural gas combi-boilers.

I don't know how it works for blocks of flats.


If you don't want fossil fuels (even natural gas), then it'll likely be a ground source heat pump. You just drill a number of deep wells -- each 100' of well gives you about 1 ton of heating/cooling (1 ton is 12,000 BTU/hrs or ~3.5KWh). For a decent sized building you'd be looking at probably a dozen or two 1-2K ft deep wells.

The nice thing is, you don't need much room on site, you can even drill them into the basement after the foundation is done before the steel goes up.

With a split system, the heat-exchangers can be in the basement and the refrigerant (R410A) run to the air handlers located elsewhere.

Of course, the more you insulate the building, the less heating and cooling you need.


Heat Pump Domestic Water Heaters are becoming very popular, plus you can combine them with a Drain Waste Heat Recovery system that would provide you with a very efficient system, that you could take long showers. This system would be a good for the environment but a hard sell compared to 90+ efficient natural gas boiler systems.

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.

There is no evidence this is really possible. Houston homes cooling a house 25 degrees will still be significantly less than maintaining a 100 degree difference in Minneapolis during a -30F snap. Don’t forget that there is significantly less daylight to work with in the winter for this “passive heating” too.

There's plenty of evidence. One example is Passive House standards (which can be applied to commercial contexts as well), which reduce heating loads by 90% using the methods I discussed. There's a lot of factors you're not accounting for:

1. Waste heat from lights, equipment, and people is constantly offsetting the heating energy, and contributing to cooling energy. There's so much equipment in office/commercial buildings, it's common to need air conditioning all through winter.

2. It's not just air temperature difference, it's also about solar radiation gain. Even in cold climate zones the peak load for cooling is significantly higher then the peak load for heating.


Passive house standards don’t cut it. Reducing 90% doesn’t matter if many of those energy improvements also apply to cooling.

> Waste heat from lights

Use LEDs and this is irrelevant for a home.

> people is constantly offsetting the heating energy

Insignificant in the scheme of things. Humans can’t even keep themselves warm when holding still in 50F.

> it's also about solar radiation gain.

Do you realize how little sun cities in the north get during the winter? Conversely, solar electricity can conveniently capture plenty of electricity quite near the time it’s required in the South.

Peak air con time is when there is solar radiation. Peak heating time is in the dead of night.


Be careful here since it gets complicated between energy efficiency differences in heating vs. cooling, but also in greenhouse impact of the units themselves. For example, R410A used in modern A/C units is over 2000x more potent as a greenhouse gas than straight CO2, and A/C units leak quite frequently as they age. You also need to factor the greenhouse impact of the energy source of the local power grid during the season when heating/cooling are needed. It's hard to make a solid claim either way without looking at quite a bit of data.

A lot of texas power grid is renewable however, which helps tilt the scales.

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.


> hydro

Okay, the power company is named Toronto Hydro, but it buys electricity from whatever is available on the grid, be it hydro, gas, nuclear (Darlington wasn't built to power Ottawa...), wind (hello Chatham farmland!) or solar.


Ah I am humbled, I didn't know that.

Heating energy is highly dependent on insulation and energy source. In northern cities with CHP powered district heating & heat recovery ventilation, it's fairly good. This in addition to the nature of thermodynamics which makes cooling quite energy-inefficient to start with.

(Of course cooling could also be done with energy efficient city district cooling like they do in some places...)


Few places in the world get hot enough to kill you outright inside a house. Most of the north (and south in the southern hemisphere) gets cold enough during winter nights to kill without heat. I guess it's puritan now to not want to die?

It’s Puritan to view air conditioning as a new-fangled luxury, while viewing heating as a necessity.

50,000-70,000+ people died in Europe in 2003 due to heat. “Gets hot/cold enough” eyeballing notwithstanding.


well don't forget that petrol vehicles tend to run rich until they get to a good operating temperature and you can see these spikes. in some cases it can be worse in winter than summer.

as others will point out, moving is not an option but improving energy sources and how its expended are the "well duh" means to manage it. the issue there of course is the scale is beyond what most can conceive and even some who think they understand the scale undershoot by a lot; akin to why some people wonder that it is so difficult to deliver high speed internet to everyone.


Thermodynamics isn’t against your quite so much with heating.

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.

IMO evap isn’t even worthy of consideration when discussed in the context of the south where you’re dealing with 90+% humidity.

By evaporative cooling I mean using controlled phase-change of a cooling medium in closed-loop condensation/evaporation coils, not something analogous to a swamp cooler. Sorry if I wasn't clear.

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.


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.


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.


The closer you get to the equator, the more you're likely to see these. When I was visiting Turkey, I didn't notice them in Istanbul because most rooftops are not visible from the street, but then I visited Safranbolu, a small tourist town, and there almost every century home had this recently-made metallic hot water tank on top which completely destroyed the bucolic architectural character of the town.

One of my uncles here in Canada built a passive system by just putting a giant 1" PVC tube coil on the backside of his roottop to heat up water for the swimming pool, since the swimmable season is pretty short anyway.


Not sure if it’s exactly what you’re talking about, but something similar is pretty common in China as well. I’ve heard people call the system “solar power“, but what they’re referring to is effectively a tank of water on the roof that is heated by the sun which is used as the hot water source for showers, etc.

It is very much solar power, it's just not fancy high-tech photovoltaics.

> 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.


Solar water heating has been on the decline recently because photovoltaics & heat pumps surpassed them thanks to ridiculous scale & modularity.

A refrigerator consumes 200 watts. That is equivalent to 2-3 old lightbulbs. Sorry, but there is nothing to heat up with this power, even if you could use it 100% efficiently. For reference a water kettle is 1200watts.

I understand the coefficient of performance for a heat pump in a refrigerator can be 5, so consuming 200W of electricity, you can get 1200W of heat. (But that heat won't be hot enough for boiling water.)

It could be hot enough for a pre-stage on a water heater. Many houses don't have the fridge close to the water heater, but some do, and if you were designing a house around a system like this, you could choose your layout.

Sure it only consumes 200W but it moves a lot more than that, which is what can be taken advantage of instead of radiating/convecting it off the back of the fridge

Sounds very interesting! I'd love to learn more if others could chime in

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.


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 :).


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.


For most houses in the south, if your having humidity problems in the 75F range your system is to large. AKA, flipping the AC on, and blasting a lot of air with a 35F drop into the house, then cycling off for 70% of the time doesn't remove nearly as much humidity as just running a smaller system closer to 100% of the time. Further most homes not built in the past 15 years are hugely flow constrained and mis balanced. So the AC runs, but doesn't provide even airflow so there are hot/cold spots.

For areas where its not 90+ out for 8+ months a year, a large part of the comfort of the newer systems (and their larger SEER ratings) is that they can run at 1/2 speed (or whatever) to keep the AC unit running longer. Plus they are frequently sold with duct work upgrades.

This is also why a "properly sized" system with a high EER can frequently save money over a high SEER system with a lower EER in FL/TX/LA/MS/etc.

The problem though is that pretty much 100% of AC companies are just going to put in the same size system as they took out, and the home builders are just seat of the pants overspecing everything. It should be possible to determine heat load, and TXV flow/etc over a year, and then come back and resize the condenser/evaporator/airflow to go just slightly over the worse case. But no one is going to do that, and if they mess up and the customer can't keep the house at 78F when its 110 out, its going to be a costly problem to fix. So, better to just overbuild everything and deal with the significant efficiency decrease.


> 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.


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.

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


Thank you for sharing that. It's an interesting claim but sadly it doesn't say what the name of the report was. It sounds a bit odd to me, though. Surely you cool down by expending less energy, unless you spend that energy to actively respire to expel heat like dogs do.

I can't imagine there are many people panting in their warm houses though.


Yes it takes energy to actively reject heat. From a thermodynamic standpoint, cooling isn't free.

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.

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.


> 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.


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.


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


Nahh, I just run hot. I've lived in a shared place where I don't control the thermostat and the person who does was loathe to let it go above 77 degrees. After months on end, I'd still get uncomfortably warm in such a temperature. On the other hand, I can sit comfortably in 55 degrees in short sleeves with wind. I also have very low body fat, so that's not the culprit either. Believe it or not, people have different preferences and optimal temperatures. I just wish everyone would err far to the side of cold: you can always put on a jacket; I can't keep taking clothing off.

Given the amount of environmental damage that energy production causes, expending huge amounts of energy to keep a large volume of space at a precise temperature rather than being a little flexible in how you dress seems pretty selfish to me. (If there was an appropriate Pigovian tax in place then I'd say fair enough, it's your money).

I wish the boss would accept that, workplace dress code means blasting the A/C all summer.

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.

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 100°F, 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 65°F inside, this process happens faster than if it's 75°F.

No doubt, the moment you get inside, you already feel better whether it's 65°F or 75°F because neither one is 100°F. But if you're alternating between inside and outside a lot, colder is still preferable.


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.

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.

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).

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.

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...)


Huh, I always assumed it was due to minimum temp laws, where it was cheaper to just heat everything full blast and never have to worry about a 1st floor or basement apartment not getting enough heat, and cheaper than installing valves or thermostats in every unit.

Every apartment I've lived in around NY and North NJ was like this. All had steam radiator heaters, and the heating was so hot, especially in the fall and spring, that you controlled the temp by opening or closing the window over the radiator. All but one also had single pipe radiators[0], so you couldn't turn them down with the valve or you'd end up filling the radiator with water and breaking the system.

However parts of NYC do still have steam heating powered by a central plant (mostly ConEd iirc) so in the end it might actually end up more efficient with the windows open than having a per unit heater.

Edit: Wikipedia link on NYC's system https://en.wikipedia.org/wiki/New_York_City_steam_system

I guess it's just Manhattan that has central steam, but it also provides cooling via absorption chillers and steam for disinfection. Also much of this steam is basically a waste product of electricity generation, so the actual efficiency may be even higher.

Edit 2: I also found and article in NY Times that supports the spanish flu as the reason for this, and also describes 1 vs 2 pipe systems.

[0] https://www.nytimes.com/2016/03/13/realestate/radiators-stea...


Overprovisioning to ensure demand is met in the worst case also sounds like a very early-20th-century sort of design decision; that could be part of it!

Here's an interesting article about Spanish flu and radiators: https://www.bloomberg.com/news/articles/2014-02-17/our-indis...

"engineering manuals from the 1920s dictated that radiators and boilers be manufactured large enough for 'the coldest day of the year, with the wind blowing, and the windows open.'" (!)


>Overprovisioning to ensure demand is met in the worst case also sounds like a very early-20th-century sort of design decision

We're building 600 hp electric cars these days.


My parents live in England and visited the US. They are used to wearing jumpers in the house in winter. But they reported that the houses were always "freezing" inside despite being warm outside. Similarly, my girlfriend, who grew up in the US says she doesn't like air conditioning because it's "too cold". I don't understand this. You are supposed to use it to be comfortable, not cold.

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.


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.

Sounds like it might be low on coolant, you might want to get it serviced.

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.

wow, you're lucky your a/c didn't freeze up

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.


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!


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.


It's the dry air that makes people sick who aren't used to living with an AC, I see it in the office every year. I'd say Barcelona is right around the area where an AC makes sense, you have 2 months per year being a little annoying but nothing unbearable. Also, it still rains in summer.


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.

All of that is dependent on location. If I dig a basement I'm under water.

Designing and building are two separate things. It may be easy to design but it is likely harder or slower to build compared to just slapping together slatted house beams. Although I wonder how much room for economy of scale growth there would be if hobbit homes became fashionable.

I learned that from James Burke on Connections:

https://www.dailymotion.com/video/x68uf3j

He says it was for treating malaria though.


Yet another misery conquered by technology.

Evil, unholy technology!!!1

https://en.wikipedia.org/wiki/Cool_Air


> Characters: Doctor Muñoz: 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.


By the same measure, The Wire or Django is racist for using the n word... It's a work of fiction, the characters and the narrator are fictionalized artistic devices and don't necessarily represent the author's views.

Is that racist? Why? Obsessions over bloodlines and breeding have existed even in homogeneous societies. Not to say Lovecraft wasn't a racist -- he was.

racist/classist... at that level it's the same thing.

And why is your handle a typo away from the respected MalwareBytes name? (Other than to sow confusion, of course)


What a splendid read! Thanks for the link. Here's the original short story:

https://www.hplovecraft.com/writings/texts/fiction/ca.aspx


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...


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/


The podcast "50 Things That Made the Modern Economy" has an episode about this: https://www.bbc.co.uk/programmes/p0504qtn.

It'd be nice if someone could properly design a dual-hose portable A/C with attention to soundproofing and efficiency. Lots of people will be needing these over the next few decades. I recently bought one, and found the low-hanging fruit to be pretty pathetic: https://pmarks.net/ac

(The ability to wirelessly integrate with a standard thermostat would also be nice; I'm currently hacking that together using ESP32 modules.)


It depends on how you define air conditioning. The story from the article describes different technologies from the modern AC unit: cold water and evaporative cooling.

But already the ancient egyptians used evaporative cooling for their homes.

And with an even looser definition, we might include root cellars. They are also rooms with controlled temperature and humidity, dating even further back than ancient egypt.


>"In 2018 the International Energy Agency predicted a coming “cold crunch” driven by a combination of three key factors:

Incomes will continue to rise in the emerging economies, where one of the first spending choices is for a window A/C unit."


I thought it was first for watching movies.

https://wfpl.org/air-conditioning/


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.


Its interesting to think that a submarine would require air conditioning with average ocean temp being pretty cool. I guess it was because of the extra heat produced by the engine and other machines?

Yes, heat, humidity and odors (basically air pollution) are a problem in subs. Subs are so awful to live in that the crew always gets the best food and amenities possible, but before AC I think they worked shirtless.

They have layers of insulation for both thermal and acoustic reasons.

Subs and torpedos are interesting to study since navies and inventors really struggled to make viable models, and probably a higher percentage of sub pioneers died than in aviation, which is saying something.


> 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.


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.


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.


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.


> 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.


"John is" is not contracted to "John's", so it's confusing to have "It is" contracted to "It's".

> "John is" is not contracted to "John's"

John's not sure he agrees.


> "John is" is not contracted to "John's"

It is, actually. It's just best avoided due to confusion unless you're doing it for quoting or dialogue purposes.

https://www.writersdigest.com/write-better-fiction/contracti...


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.


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.

Goes to show I shouldn't trust something, just because it was taught to me in school...

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!


There isn’t anything irregular about it, pronouns are just different from nouns. His, hers, yours, ours, theirs, its.

> 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


The author is not a native speaker. https://en.wikipedia.org/wiki/Vaclav_Smil

As a native speaker, it bothers me quite a bit.


As a native I'm always annoyed by the stupidity of English spelling and grammar. Two words pronounced the same, but spelled different. In spoken conversation we have no problem figuring out what is meant, but somehow we think readers are not smart enough to figure it out?

English spelling is badly in need of reform.


> as a non-native speaker I’m always shocked by these basic errors made by natives

After some years of living in an English speaking country, I started to make these native errors myself. Maybe they are not native, after all.


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


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


I can only remember the rule by remembering that “its”, “his”, and “hers” are pronouns and none have apostrophes.

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).


> 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.


I looked into this exact topic a few months ago when a cake decorator friend wanted to know what to write on the cake board for "name's christening" but the child's name ended in S. I applaud the attention to detail :)


There's an article on the front page about Perl 7, I'm starting to wonder which one has the more difficult grammar ;-)

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.


Genitive -s works in other languages (eg German) without apostrophe and without confusion.

How strange that the world does not want to use German as its lingua franca then.

Genau, jawohl! :-)

How do you know the author is a native speaker?

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.


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.

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.


> 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.


I couldn't think of an example that would trip up a native speaker. What was an example you had in mind?

I can think of a few two word statements ("It's tender") but they are meaningless outside of context anyway.



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