The gist: On hotter nights people get less sleep, this being especially the case for people who are poor (limited access to AC?) and who already live in hot climates (100->110 deg is more noticeable than 70->80).
It’s nice data. They gave sleep tracking watches to 47,000 subjects for a few years, and this is what came out of it.
Their climate change angle is suspect. It probably helps publish to be relevant to a real-world problem. But their final paragraph undermines the projections they try to make: people adapt to the long-term weather patterns, and they’ll likely partially adapt to climate change occurring over the course of 50 years. Of course it’s still relevant from a health equity standpoint to consider.
>The gist: On hotter nights people get less sleep, this being especially the case for people who are poor (limited access to AC?)
Forcing a large part of the world where noone has an AC to get an AC (at least those that can afford it) is going to do wonders for the environment.
I'm quite sensitive to heat and the quality of life improvements from an AC are immeasurable, though I live in an apartment and can't really get one (have a crappy portable one for emergencies). I suspect that the climate impact of the ACs are going to create a strong stigma against it where they are not strictly necessary.
>Forcing a large part of the world where noone has an AC to get an AC (at least those that can afford it) is going to do wonders for the environment
Sure, but then why does the US get a pass on being super environmentally unfriendly by running heating or AC at full blast everywhere while also having buildings with very poor insulation (by European standards at least; the single pane windows with no outdoor blinds I had in Miami Beach would be illegal in most of EU) and no outdoor sun shades to block the sun energy entering the building, choosing instead to vent it out via AC after it had already entered, or just straight up wasting energy (Las Vegas casinos run the AC basically outdoors), while other, usually poorer countries, should just suck it up and learn to live without AC?
I get that the US is capital and resource rich and can afford to be wasteful with almost everything, but the climate impact is still global.
Building codes in the US are laughably sad. I've built 3 homes in 2 states and never built to code. I always encourage people who are building to view code as the minimum, but who wants a minimally good home? Apparently most people. The big builders want to put something up at the lowest cost.
Building codes need to be raised to a higher level. It saves money in the long run and is better for everyone.
It's still incredibly wasteful. I remember studying in the LA area not so long ago and I had to bring a sweater to class even though it was 30c+ outside
> the single pane windows with no outdoor blinds I had in Miami Beach would be illegal in most of EU)
Was this a while back or very old building? My understanding is impact windows are required less than one mile from the coast. Beyond that insurance drives their adoption as premiums rise significantly without wind mitigation.
AFAIK most homes with poor insulation where build when energy in the US was dirt cheap (relative to the median income) and it was rational to save money on insulation and just blast powerful AC (human effect on global warming was not known/established back then). Retrofiring insulation into already built homes is not cheap.
We are all doing a terrible job of it. Don't get me wrong, the US is worse than most but I don't see that as an argument for others to not give a fuck.
Because it seems the US isn't doing much on this front IMHO, despite being the richest country in the world, therefore having enough capital to improve and set examples. Especially with Trump pulling the US out of the Paris agreement. Granted, Biden rolled that back, but still, the deed was done and it sent a bad message to the rest of the world on how the US feels about the environment on the world stage.
>the US is worse than most but I don't see that as an argument for others to not give a fuck
Because, usually rich countries should set an example first before talking down to poorer countries about saving the environment. Otherwise, how can we expect poor countries to want improve their environmental impact if even the rich countries who can afford the expenses that come with being environmentally friendly, don't actually give a fuck about the environment?
This is the same inequality as fat-cats telling the working class they need to tighten their belts and suffer austerity to save the economy while they get more tax breaks, bonus payments and government handouts.
I agree. But that still isn't an argument to not do what we can.
And there are other rich countries than the US that do better. ... no it isn't enough but we are gaining momentum. And that is about the only positive thing I can say at the moment.
> Forcing a large part of the world where noone has an AC to get an AC (at least those that can afford it) is going to do wonders for the environment.
Heat pumps are better than any other kind of heater efficiency-wise. Getting a mini split is good for the environment whether or not you use it to cool.
> On hotter nights people get less sleep, this being especially the case for people who are poor (limited access to AC?)
As someone who’s fought multiple property management companies over dead AC’s I can confirm: it is difficult to sleep when you’re seeping into your own puddle of sweat. And there’s no real way to properly cool a space this humid I’ve ever heard of.
This is good to keep in mind although should you ever find yourself in such a situation know that you can still put your feet in a bucket of water. We usually get water from rivers our underground reservoirs so it tends to be cool enough even during heatwaves. It’s perhaps not the most convenient way to cool down but beats death.
I hope and expect they’ll consider dehumidification and air conditioning (which naturally “includes” dehumidification) as part of the adaptation strategy.
(I’m not suggesting that we give up on global warming, but if a people are facing 35°C WB, AC/dehumidification is going to have to be part of the answer, because the next 5 years of climate is already cast and the only other short-term alternative is “well, move” which is far less practical or empathetic.)
> they’ll likely partially adapt to climate change occurring over the course of 50 years
We will adapt by moving indoors to controlled environment, but it's not like we will evolve. At some point, the global mammalian birth rate is going to plummet because it will be too hot for sperm. Mammals won't physiologically adapt to that in a mere 50 years, but those able to live in controlled temperature indoor environments should be able to continue procreating. But when prolific procreators' (such as rabbits and squirrels) populations plummet, we should not ignore it.
I really don't understand why we can't stop Global Warming... now. The contributors to Climate Change are not typical citizens, it's instead various industries. Why are we more concerned about those industries, construction, glass, shipping, energy, than we are about the human global population (and all the other living things)?
There are physiological adaptations as well. People in hotter climates are still going to get good sleep. It’s just when there are hotter temperatures than people are used to that sleep is impaired, and also that adaptive mechanism only works so well, and there is disparate impact for people in different climates. At a certain point, there are heat waves or very hot temperatures that simply aren’t conducive to human life.
100% agree about the urgency to make an economic system that is compatible with climate stability and thus with human life.
Their angle was health equity in the context of global warming and how it impacts different populations to various degrees. That’s a common trend in global warming related issues. Their argument is fair enough.
My issue with the paper was specifically with the projections they made, which extrapolated the effect on sleep caused by the weather all the way to effects on a 50-year interval caused by warming trends. But by the authors own admission people can physiologically and technologically adapt — at least partially — over long enough time periods. To be frank I think it’s a way to make a compelling headline. They have the statistical tools they have, it would be incredibly hard to account for long-term adaptation, and so they come up with some statistical estimate of the long-term trend. I see why they did it, but from a readers perspective it’s okay to be critical.
The fact that heat stress affects different populations with such different impacts is super important to climate policy and diplomacy and geopolitics. The authors in this case identified a concrete, statistically sound demonstration of disparate impact of heat stress.
That’s something I wish I had emphasized in my top-level post.
This comment won't do well right now but I suspect in the future we may come back to this idea. I believe more work needs to go into automation of forming/welding frames for underground homes as the temperature is rather constant under ground. 3D printed/molded? Some locations will need specially built units that can handle moisture. I have probably binge-watched too many mining/tunneling videos but I could see this technology becoming affordable to the consumer through technological optimizations, maybe? Anyway moving the home under ground could provide additional room above ground for a garden or parking spots. Underground homes would also be tornado resistant. Another advantage is energy efficiency or moving towards being carbon neutral. There are concrete / shotcrete companies making carbon absorbing material now.
I am thinking of the real world example of Coober Pedy, AU [1] They have subterranea hotels, mines, homes, recreation facilities and more. If I ever went to AU that would be my first stop.
Anecdotally my home is partially earth bermed and even on hot days hot being around 101F it is cool in my home and I do not even own a HVAC unit. One of the many reasons I moved was due to heat and sleep issues.
Agreed if you mean WE as a hypothetical union of all individual humans and human institutions. But all of this makes a lot more sense to me if you distinguish between individuals and institutions. Institutions (companies / governments / Unions / HOAs / PTAs w/e) seem like they're impossible for any individual to control except by collective action which is just more institutionalization thats impossible for individuals to control. Individuals can make decisions to do things like install solar panels on their house, invest in a heat pump, buy an electric car, live in walkable areas, plant a garden, NOT work for or purchase things from institutions they disagree with, build an underground house etc within the confines of what institutions will allow. I don't think theres any more that we can do, the rest seems like subjugating guilt narrative bs and self-satisfied collective action virtue posturing.
There is no WE imho, its individual human beings against global industrial institutions. Collective action just propagates more destructive / uncontrollable institutional behavior. Federated / decentralized individual action propagated through federated / decentralized communication networks.
Anyway I can barely remember to brush my teeth or buy groceries so what do I know.
Living underground tackles the one issue that no green revolution is going to fix - space. Above ground space is fixed and the population will continue to rise. We can build upwards or downwards but upwards blocks light, which is also a fixed quantity.
living space isn’t remotely a concern, if we all (the whole world) lived in a single mega-city as dense as NYC it would be about the size of Texas
light also isn’t much of an issue, we could power the world with a solar array the size of New Mexico
fertile farm land, stable temperature, and distribution are much much much larger issues
living underground might be good for reducing electricity needs for heating and cooling, or avoiding certain natural disasters… but probably isn’t very useful for much else
Also the buildings themselves still get the light and can funnel it into living/working spaces or just turn it into electricity. Sure it’s shadier at ground level in a tall dense city but like, I’m pretty sure it’s more feasible to build km-ish tall buildings that still manage to post some light down to street level than it’ll ever be to build living space that goes equivalently deep.
I fully support tackling the root causes. That said I can not do that by myself and my experience interacting with governments has unfortunately made me a bit cynical.
What I as an individual can most certainly do is install a modular home under ground if a company were inclined to make one, preferably out of recycled material. I could rent an excavator tomorrow as they are closed on Sunday.
I have a theory that if enough homes were underground that would substantially reduce the load on the power grid from a lack of HVAC use, freeing more capacity for EV vehicles and buying more time for power companies to upgrade the power grid and reducing overall carbon emissions world wide. Perhaps power companies could lobby governments to make under ground homes affordable, modular, carbon neutral and most importantly safe. The wealthier and more influential people could even have underground garages to protect their expensive toys from the environment and theft.
thing is the root cause is a coordination problem, it's impossible to get 8 billion people to tackle any issue unilaterally, so we are left with solutions that allow individuals to opt in to a future where survival is not dependent on everyone else
I kind of agree, but on the other hand we are so far along that we won’t be able to stop climate change but merely restrict it. So apart from restricting it we also need to adapt.
Underground construction is really hard to do correctly. Partial earth bermed foundations as you mentioned are a good compromise, especially if the earth is built up. But even then, drainage and soil pressure are big engineering concerns.
Also you have no control over how much thermal interface you have. My office is on the first floor on a slab. It's great in the summer and freezing in the winter, despite a carpet.
Digging down becomes increasingly expensive vs equivalent volume building up.
Why not just use ground source heat pumps? It's much easier to bury some tubes than habitable spaces. It's easier to move heat/cold where you need it. You aren't forced into a fixed thermal flux.
I'm really not sold on the costs of digging down being all that high, long-term.
I'm 100% sold on it being expensive today, but I can come up with ways to drive them /way/ down with automation. The critical thing is:
1) You don't need materials.
2) You don't need to transport anything other than a digger
I agree it's hard, like engineering a CPU was hard, but I think Elon's got the right idea with the Boring Company. It's not /fundamentally/ expensive. Fundamentally, building in-place with available materials should, some day, be cheap.
In this context, you do. You need material structural stability (which is nontrivial, even for partially bermed structures; digging down further is a different story too) and for human habitation. Even above-ground you see retaining walls everywhere in places like New England because dirt likes to move. Worse, you'll need relatively expensive materials, and ones that are OK with contact with a lot of moisture. Maybe plastics can be the answer to some degree, if ones that are structurally sound and not tasty to microorganisms can be employed en masse, but the default answer is probably steel, and that won't last forever (or even all that long).
Beyond that? People aren't generally high on dirt walls and floors. And smoothing stone to presentation levels in-place, ensuring regularity, etc. is not a trivial task.
It could be done, don't get me wrong. But we have wear and decay problems above the surface that probably pale in comparison.
I feel like the materials are whatever is found on site.
That may mean that a machine may need to be able to sort, smelt, sinter, form, ram, engrave, or otherwise process whatever it found on-site.
That's definitely non-trivial, but in the sense of making a CPU with millions of transistors, and not in the sense of Mt. Rushmore. The R&D costs will be astronomical, but there isn't much there which is /fundamentally/ expensive, at least so long as you're not going to deep.
I can describe a number of beachheads and early markets -- places where you don't need all of that at one, or ultralow costs. I think the Boring Company has a decent one.
Underground construction is really hard to do correctly.
I agree it is harder to do correctly and costs more. It's an investment that if done right could outlast any above ground home. But that is quite a loaded caveat on my part, done right. That's why I envision this being done in a factory and very specific instructions and compliance requirements that if adhered to should produce more predictable results. The bunkers I see people building today are all custom one-off designs and I think that is where they get into trouble.
I do like the idea of heat pumps. That would be a balanced trade-off for those that do not want to mess with putting in a home under ground.
>It's an investment that if done right could outlast any above ground home.
I would think this was true, but what I've learned so far suggests it's not...
Underground, you're not finding refuge from harmful forces on your structure; they exists there too. Things shift, things crack, things leak, humidity causes problems, the whole exterior now endures a chemical interface with the surroundings (and all your Vault-Tec steel will corrode at some speed determined by the nature of the local media).
If you're lucky enough to have near-surface bedrock where you are, digging into that is probably your best bet, but, even then, it seems like an uphill battle.
In the summer you'll want the surrounding ground to take away the heat, but in the winter that will be too cold, so you'll need to heat your home. There will be some (well quite a lot actually, as you don't have any insulation if you want ground cooling in the summer) waste heat transfering into the surrounding earth. Over time that will heat it up, so in the summer it'll be less effective at cooling.
This is actually why the London Underground is so hot in the summer. It wasn't always like this, but over time the ground surrounding the tunnels has heated up.
I suspect that if a subterranea home were built so poorly that radon gas is infiltrating the walls then so would water. Both would have to be factored into the design. Modern bunkers are designed to keep radon gas out and are equipped with high flow ventilation systems. High pressure shotcrete or some similar material should more than suffice to keep gasses and water out.
Radon is a problem in traditional brick and mortar basements as those walls are typically just one layer of brick and mortar. Water and radon can easily penetrate through micro-cracks that develop over the years in traditional basements.
"I suspect that if a subterranea home were built so poorly that radon gas is infiltrating the walls then so would water."
I'm no expert, but your statement makes me ask... Why then do we have homes with basements that have radon problems, but not water problems? I don't think the two problems are always related.
Water infiltration depends on the amount of water and type of soil and the drainage designed into the basement. e.g. layers of concrete and rows of shale/rocks for drainage. Not all basements are equal. The amount of radon depends on the quantity of uranium and thorium in the soil/dirt. So you are right they are not always related but the mitigating controls can be potentially related. Some construction companies just focus on maximizing profits in my opinion and some individual home builders will use construction dirt that contains low or no uranium or thorium.
True, though it appears to be the same liquefaction risk that above homes are subject to. [1] Geological surveys would be more important and I suspect compensatory insurance would be harder to acquire. That said if the automation brought the cost of these units down far enough then perhaps only liability insurance would be required as the unit could potentially be recycled if it were designed with that in mind. One could rent an excavator at $150 to $400/hr depending on size required to remove the top soil. If the rooms were modular then the excavator could lift or maybe even drag out the damaged room to be swapped out. If not modular then a crane would be required.
There are bomb shelter companies designing underground facilities that can withstand earth movement and allow the occupants to escape harm. I won't link to those companies as I feel they are over-priced and this could be done much more efficiently with advancements in automation and recycled materials. For small facilities like homes I believe this is a mostly solved problem.
A harder problem in my opinion would be a commercial mine due to the size/scale. Steel I-Beams and steel plates throughout a lengthy/deep mine would be very expensive as opposed to the wire mesh and 8' anchor bolts and shotcrete used today. A modular home would be far less likely to cross liquefaction and plate fault boundaries.
I definitely sleep less well in the hot, humid, summer than in winter. When it's cold you can add layers. When it's hot you reach a limit of zero layers of clothing/coverings and then have to move the heat and humidity elsewhere artificially via A/C.
I also think (this is my subjective opinion, I have no proof) that cold reduces swelling and inflammation, thus making for easier breathing during sleep.
Just having a regular fan helps a lot. Very little energy usage, very cheap. I bought a new fan a few weeks ago, one that is nearly soundless in its lowest setting. Even the slight breeze made by the lowest setting already makes a huge difference compared to stale hot air. It also uses an order of magnitude less energy than an A/C, and costs an order of magnitude less to purchase+install (100 EUR vs 3000 EUR).
If you live in a place like London, where it gets hot in summer but many places still don't have A/C, a fan can work wonders.
Here's the magic trick to cool your home down quickly:
During the day your house heats up. In the evening your home is likely warmer than the night air. Many people try to open the window and put the fan close to the window to blow cold air in.
What works much better is pointing the fan out of the window!
I installed a whole house fan in my previous place. Automatic louvers in the attic and a massive blower that I could open downstairs windows, turn the fan on and it would pull air in from the windows, push it into the attic, and out the louvers.
Not only did it quickly replace the indoor air with cooler outside air, it would also ventilate the attic, preventing it from quickly reheating the upstairs. I could run it for 5 minutes and get the desired effect, maybe 10 minutes in an unusually hot spell.
I used the technique I described in eg London, Sydney and parts of Germany. Most of the time, temperatures had dropped quite a bit by 22:00. (But not always.)
That depends on where you live. I used to live in a place where the lows are night were still very warm. Most of the night was too hot. Just before sunrise there was a moment when outside air was worth bringing in - but it was only long enough to cool the air in the house, not the mass of the house itself.
Now I live in a cooler climate. The highs can still get as high in the day, but it does cool of at night - nearly as soon as the sun goes down.
This - create a negative pressure space inside the house. Then open other windows throughout the house to equalize that pressure. By pushing air out one window, you’re effectively creating a breeze from many windows. It’s also easier to push a large volume of air out of a window than to try and pull a large volume of air from outside a window.
This is the last thing you want to do. By creating a low pressure zone in your home humid outside air will seep in through every crack, gap, and uncaulked seam in your house.
Such a system is basically a mold incubator. The correct method is to:
1) have central HVAC
2) have an energy recovering ventilator (ERV), zhender is a good brand.
#2 Constantly cycles fresh air throughout your home and it’s intake is controllable and filtered.
My suggestion was for situations like London or Germany in summer. The air cools down a lot in the evening there, and people typically don't have any A/C there nor humidity problems in summer. The point-fan-out-the-window technique is for rapidly bringing your home down to ambient temperatures (and humidities).
There will be no condensation, and thus no mold, because the ambient night air is above its dew point, and your own walls start out hotter than the ambient air, and they only approach its temperature _from above_ as you ventilate the house.
What you are describing sounds like it might be more appropriate for something like Florida.
In places like Germany or London, people have mold problems in winter, when the walls are colder than the air in the home.
(You can also get mold problems, when you are running an AC.)
The humidity in London is currently 69%. Your indoor humidity should never exceed 60%, and you should target 40%-45%. If you have no way to control this then you are essentially running a mold incubator.
From my travels around western europe I also noticed a SHOCKING number of bathrooms lack any form of bathroom fan, so hot showers spike the indoor humidity and it stays there.
>The point-fan-out-the-window technique is for rapidly bringing your home down to ambient temperatures (and humidities).
Sure, but the goal is to do that in a controlled manner. Every outlet needs an inlet, and that inlet can either be a dedicated one with a filter (via ERV) or cracks, crevices, and air leaks around your house that you can't see. By puling in uncontrolled outside air you risk moisture buildup in those areas that can lead to mold and rot.
>There will be no condensation, and thus no mold, because the ambient night air is above its dew point, and your own walls start out hotter than the ambient air, and they only approach its temperature _from above_ as you ventilate the house.
Unless your interior air is humid, because the house lacks even the most basic form of humidity control. Then those air leak spots cool the area they're leaking in around which then makes condensation from your interior humidity.
>(You can also get mold problems, when you are running an AC.)
Oh for sure. My point is that a house with proper AC, humidity control, and ERV will be extremely resistant to mold growth. It will also feel fresh, comfortable, you'll sleep better etc.
Where do you get your 60% humidity ceiling from? I live in Singapore these days, we currently have 80% humidity (and that's fairly normal). We have much less problems with mold here than in Britain or Germany.
(In Germany, problems with mold were usually in winter, anyway.)
Yes, bathrooms with neither windows nor fans are annoying.
> Sure, but the goal is to do that in a controlled manner. Every outlet needs an inlet, and that inlet can either be a dedicated one with a filter (via ERV) or cracks, crevices, and air leaks around your house that you can't see. By puling in uncontrolled outside air you risk moisture buildup in those areas that can lead to mold and rot.
Eh, the air will mostly be pulled in either through another open window (good), or through the same window you are blasting the hot air out of (slightly less good), because your fan doesn't form a seal.
I don't really see how you are getting your moisture build-up. You only really get condensation on the walls, when your walls are colder than the air.
> Unless your interior air is humid, because the house lacks even the most basic form of humidity control. Then those air leak spots cool the area they're leaking in around which then makes condensation from your interior humidity.
I never heard of anyone having that problem in summer, and never had it myself.
I have no clue where you are taking your worries from.
Yeah can confirm that's doable, unfortunately it's very disruptive since you need to keep light levels down before opening windows and during it otherwise your place becomes mosquito and moth central.
The silver lining is that it will get better eventually since bugs are dying off rapidly but for now it's either eye strain or buying nets for every window.
> What works much better is pointing the fan out of the window!
I just remember: hot goes to cold. So pushing the hot air toward the cold air is more efficient. If that means pushing the hot air inside the home toward the outside then sobeit.
I don't see that it matters much which way the fan is blowing. What matters is the air exchange, which is about creating an airflow.
If you have a multistory house you can open windows at the top and bottom, the warm air will tend to flow out and pull cool air in the bottom. In that situation if you have a fan, it would make sense to have it blowing air in on the lower level, or out on the upper level.
If you have a single level, the fan will just create a slight pressure difference in one direction or the other. You just need to open several windows, preferably on opposite sides of the room, and if you use a fan to pull cool air in that creates a positive pressure inside the room, which will force the warm air to be exhausted through the other open windows. If the fan is blowing warm air out, then the room pressure will be negative relative to the outside, and cool air will be pulled in through the other open windows.
Yes, it's best if you can create an airflow from bottom to top in a multi-story place.
Getting a draft through your entire place is also good.
What I suggest with the fan works, when you can't do either of the two above.
> I don't see that it matters much which way the fan is blowing. What matters is the air exchange, which is about creating an airflow.
The latter explains the former. A simple experiment: sit 2m in front of a running fan, then sit 2m behind a running fan. In front, you will feel lots of airflow, behind you will feel almost nothing.
That's because the fan 'pulls' air in a diffuse manner, but pushes it as a directed bundle.
It's probably equally as effective to put your fan outside the home and point it inwards, or to put it inwards the home and point it outwards. Alas, most people can only put the fan _inside_ their home, perhaps at the window at best. But that's less effective at exchanging air with the outside than pointing it outwards.
> If you have a single level, the fan will just create a slight pressure difference in one direction or the other. You just need to open several windows, preferably on opposite sides of the room, and if you use a fan to pull cool air in that creates a positive pressure inside the room, which will force the warm air to be exhausted through the other open windows. If the fan is blowing warm air out, then the room pressure will be negative relative to the outside, and cool air will be pulled in through the other open windows.
To use your terminology: the fan is better at pushing air in a concrete direction, than at pulling air from a specific direction.
Your results seem rather strange, though. I wonder where the extra heat came from? Thermodynamics say that heat moves from hot to cold places, unless something intervenes.
If you do, you get A/C for 'free', and if you don't, you're wasting so much energy in the winter that you can never make up for it by 'making do' with a fan rather than proper air conditioning.
Signed, some guy who was in Belgium for the heat wave in 2018 and thinks Europeans should just suck it up and put in heat pumps. Sweltering in the summer and burning gas directly in the winter isn't virtuous.
Everyone who has heat pumps knows they can cool, the issue is getting one because they kinda cost like 5x as much as an equivalent AC unit for some goddamn reason and the only difference is the reversing valve. I suspect the market needs some EU regulation so the manufacturers stop price gouging based on marketing bullshit.
On amazon in the US you can get either a 12,000 btu through-the-wall AC unit for about $700 or a 12,000 btu wall ductless mini-split(heat pump, so AC and heat) for about $850. For either of those you can find models for cheaper or more expensive. I just chose general middle of the road prices. So the cost is no longer 5x, the prices are becoming a lot more comparable for heat pumps vs regular ac units. Also, if you check out the efficiency ratings, for most mini-splits these days, you'll make up the cost difference in your electrical bill vs a run of the mill AC unit in the medium to long run.
Your mention of through-wall models reminded me: I've been wondering for a while why I can't get window-mounted heat pumps at a reasonable price. I recognize the limitations on insulation, but as I'm not yet at a spot in my renovation where I can do heat pumps comprehensively and seeing as how I'm looking for another air conditioner for the first floor of my house, buying one that's reversible seems like an obvious thing. (Maybe like that around-the-window Midea model? That seems kind of obvious to me, but I am not an engineer.)
This startup has a neat idea, and I hope to see more about it - https://www.gradientcomfort.com/ - but $2000 feels like it's not competitive.
And if anyone happens to know of one (and not an AC that will just do electric heat) available in the USA, I'd be grateful to hear about it. Amana will sell me one - for $1300 for 12K BTU, and that sounds...high.
I have been researching heat pumps, in my case air-to-water, so I could get very cold water “cheaply” in the summer, but it’s still a massive project to turn that into AC.
I probably can’t make it work, because I need a bit too high water circulation temps to meet the heating load at 12°F/-11°C and the up-front economics are significantly worse due to not enough experienced installers/general lack of competition in the air-to-water space. (Our gas prices are low enough and electricity high enough that the payback period is lengthy.)
If I had existing ducts, air-to-air heat pumps would make a lot of sense (and would give AC automatically), but hydronic distribution doesn’t afford “free” AC.
I live in the Boston area (temps well below freezing in winter). Freezing is managed by either a monobloc design using glycol in the outdoor loop (more common) or by sending only refrigerant in/out of the building (less common) and having the heat transfer take place inside.
If you use glycol, you’d typically use a plate heat exchanger inside and still use water as the main hydronic distribution medium (out to radiators in my case or to floor warming in other installs), but this gives up a small amount of efficiency and some maximum heating capacity. (If the max leaving glycol temp is 130°F/55°C, your max water temp will be a few degrees below that after the heat exchanger.)
The split units (refrigerant lines in/out of the building) can go directly to water, meaning a max leaving temp of 130°F can go directly to the radiator loops.
I don't know if you watch Technology Connections already, but his videos on this are really good. He lives in the Chicago area.
I get the sense that you've evaluated this thoroughly and it actually won't work for you, that does happen.
We get bitter cold as well as sultry summers, and I have an AC which I keep thinking about replacing with a heat pump, just because it bothers me aesthetically that I can't run it backward for the intermediate months when it's cold but not that cold. The bill would be cheaper but the depreciation on replacing a perfectly good AC would take a long time to balance.
I haven’t, but will check his channel out. In return, I’ll recommend Heat Geek (based in UK). (Edit to correct: I actually had seen at least one his videos from my YouTube history. That reinforces my recommendation for “if you like him, you’ll likely enjoy Heat Geek as well”.)
In terms of “can it work for me?” it’s like most things: if you hit it hard enough, it’ll fit, but the low cost of replacing a boiler with a boiler, the high cost of electricity in MA, and the dearth of A2W heat pump companies (both competing to supply equipment in the US and locally installing) makes it uneconomical, not thermodynamically impossible. (It’s right on the edge but inside of the latter; via experimentation this winter, I determined that my 2 lower levels can maintain temp down to 10°F with a leaving water temp cycling between 125-135°F, while the converted attic needs 135-145°F at 10°F OAT. Most A2W heat pumps max out at 55°C/130°F leaving water temp, and even at that level are necessarily giving up efficiency and heating capacity as compared to a 45°C or 50°C LWT.)
Obviously, improving insulation would change those figures, but in a structural brick house with complex interior wall finishes, adding radiation in the attic and supplementing the heat pump with an electric boiler below 15°F OAT would be wildly cheaper, especially since the COP at those temps is well under 2 and the runtimes under 15°F would only be around 50-75 hours per year.
It could work, and would allow us to get rid of local fuel combustion entirely, but even after a $10K government incentive, it would be at a cost that is still a multiple of what gas-for-gas replacement ($2.5K government incentive) and running for 15 years would cost and with the risk of having an uncommon system that only a few companies understand and can service. Perhaps the boiler after this next one will be replaced by a heat pump; I hope things develop in that direction.
We may end up adding some mini-split (air-air) heat pumps, mostly to provide AC and dehumidification in the summer (replacing window shaker units), but those would also be quite economical to heat with in the long shoulder season (40-60°F OATs).
> If you do, you get A/C for 'free', and if you don't, you're wasting so much energy in the winter that you can never make up for it by 'making do' with a fan rather than proper air conditioning.
Eh, depends on what you are heating with in winter.
A friend of mine lives in a rural area and basically gets firewood for free. Even the best heat pump can't beat that.
(Heat pumps are still great in general. And much better than using electricity directly to heat.)
There's something satisfying about trading labor directly for something like heat that you normally have to buy. Exercise is good for you, sustainability and resilience are virtues, and so on.
But heating even a modest space with wood is a Lot of Work.
Also, it's still quite energetically inefficient, but that's a technicality here I feel, energy isn't completely fungible (it does salvage my sentence, which was about energy). The carbon accounting would be interesting to spitball but fiendishly hard to do fairly.
Fans work fine for hot, dry climates, by increasing your sweat evaporation rate. When coupled to evaporative cooling (fans that pump a little water to evaporate into the wind), they work even better. But in hot, _humid_ climates, they are worthless. Climate change is increasing both average temperatures and humidity in many places. Heat and humidity are a killer combo.
Oh, absolutely. I use a fan from April through May. Come summer with 35-40 degrees and 80-90 percent humidity, as is the case for six to eight months of the year in many places, no fan will help, only true-blue A/C.
Moving air also helps against mosquitoes, I have read!
Mosquitoes identify us by our CO2 emissions. So getting rid of the CO2 bubble coming out of our noses does a good job of masking us from the mosquitoes.
Not being able to heat a room above 16°C is a better problem to have than not being able to cool below 30°C but cold takes it's tool too. At night you can use a thick comforter or a couple and the problem is solved, but working behind a desk in a cold room is trying. Many layers of closing helps but it is not an ultimate answer - while being in a cold room in warm clothing I become tired more quickly than in a room at 20°C—25°C.
My guess is very few people are willing to go back to pre-A/C days. Especially in automobiles. And any attempt to persuade people to give them up is going to be met with forceful pushback. It's now a luxury few will be willing to give up.
> The elderly, women, and residents of lower-income countries are impacted most
If small increases in global temperature can impact sleep enough to care about, then that is a much stronger additional argument for economic growth( to make AC, which can reduce night temperatures by a lot, affordable and universal) than it is for trading growth for some small avoidance of further temp growth. The latter is how I expect most people will read this result...
I don't see your argument at all. I see this as a powerful reason why even seemingly small changes in temperature can have a huge impact on human life. If this was the literal only issue, that could be an argument. But it's not. It's one of many.
My hope is that people will read this and say "it's not just the animals, the plants, crops, drought, it's people directly affected too". Although I apparently overlooked the "fuck the environment, fuck the poor, get AC" argument.
The study suggests that nighttime temps over 25°C are detrimental to sleep. One of the most obvious ways to get nighttime temps well under that is via AC.
It doesn’t seem outrageous nor “fuck the poor” to ask the question “is there a reasonable path to get AC more widely deployed to help more people sleep better?”
It's not about "fuck the environment". That's an extremely uncharitable interpretation to take of your neighbors. People are willing to to sacrifice, but only IF they see it as a meaningful sacrifice that actually does something. Sort of like why recycling rates are going down because more and more people realize most of winds up in the landfill anyway.
> "fuck the environment, fuck the poor, get AC" argument
Arguing that the benefits of economic growth for the poor are underrated and supported by OP more than more politically-palatable interpretations is precisely the opposite of 'fuck the poor', and given what we know about the other benefits, probably the opposite of 'fuck the environment' too.
AC heats up the planet though (just think of the thermodynamics: not only to you pull out the heat and expel it outdoors, but that takes energy, which ends up as heat exhaust as well).
People need cool air, no question, but it's not a free lunch. We need to cool the climate as well.
(BTW I do believe everybody should have access to as much energy as the OECD countries use per capita. Sadly even this is controversial)
The name heat pump explains it pretty well. It "pumps" heat from one place to another. In case of your AC from inside the building to outside. Yes, it generates additional heat from the electricity it uses.
But ...
It doesn't matter how you use energy on earth (except for mostly weird examples), because basically except for these weird examples, almost 100 % of the used energy will end up as heat anyway. It doesn't matter through what cascade of transformations the energy ends up as heat, whether you use electricity to boil water, or to power an EV, or to power a heat pump, almost 100 % of the input power will end up as heat anyway.
What are some weird examples? You convert captured solar energy into chemical energy (for example pure carbon or hydrocarbons) and store the chemicals forever, then you've prevented some of the captured energy from being turned into heat. Another would be to emit electromagnetic radiation into outer space. Or you could carry rocket fuel into space and just dump it there, unused.
That's not correct. Every transformation has efficiency loss. If you pipe the same amount of energy through a less efficient process, less useful work gets done for that amount of energy. Therefore to hit your target of useful work via an inefficient process, you'll have to send more energy through it, and thus more energy also goes to waste (heat).
> If you pipe the same amount of energy through a less efficient process, less useful work gets done for that amount of energy. Therefore to hit your target of useful work via an inefficient process, you'll have to send more energy through it, and thus more energy also goes to waste (heat).
The point in the post I was replying to wasn't about efficiency.
The question was, whether heat pumps heat up the earth. They don't.
Why?
Because the energy that's used to power heat pumps would (as I've explained) have ended up as heat anyway.
If you use fossil fuels as energy source to power heat pumps, then yes, you convert chemical energy to thermal energy. But it doesn't matter if you use that fossil energy to power a heat pump or to power an EV or a computer, the energy always ends up as heat.
So it's not the apparatus "heat pump" that's a problem, but the fact that someone is using fossil energy at all.
No, heat pumps don't heat up the earth. Using fossil fuels does.
If you were to power the heat pump using solar energy, you'd mostly leave the earth's energy balance untouched.
The main point where you then interfere with the earth's energy balance is through altering the way that radiation gets absorbed/reflected/emitted by the solar panels as opposed to no solar panels being put up.
Some processes that indeed heat up the earth are:
- radiation from the sun (and earth) gets partially trapped by the atmosphere (absorbed/reflected)
- nuclear fission processes produce energy that gets converted to heat through a cascade of processes
Not heat pumps? No idea what you're talking about. Evaporative cooling, passive cooling, cooling by ventilation, plants. You mean these?
Well at least these AC units in cars and the humming things mounted in millions to outside walls of buldings are all heat pumps. Don't know what other AC you mean then.
As to thermodynamics, apart from using the term, would you care to explain how it supposedly explains your claim?
Maybe you arbitrarily set the earth's system boundary to the outside walls of all AC'ed spaces?
A “heat pump” is a specific kind of device that can function either as a heating or cooling device depending on its mode, basically transferring heat from one side to the other.
An “air conditioner”, as traditionally defined, is basically a refrigerator: it compresses a gas and then lets it expand through a valve; it becomes cold due to Boyle’s law (I suppose you could make one like a gas powered fridge instead of using an electric pump but I’ve never seen one). You can use that to generate cooler ambient air and then radiate it outside the way a fridge does.
And in either case the thermodynamics situation is simply the second law: it takes energy to do all that work, which turns into heat. Sure, the energy from a fossil fuel was originally solar power, but that was millions of years ago. You can’t just magically claim its part of the current energy balance.
The significant contribution of air conditioning to heat islands has been widely discussed for decades.
Yeah sure, in the practical sense different terms are established for the different applications, but that doesn't change the fact that what you call a "heat pump" works by the same principle as what you call an "air conditioner".
I was more refering to the general thermodynamic principle of a heat pump and it appears that others too use the term in that general sense.
Citing from Heat Pumps in Chemical Process Industry (by Kiss, Infante Ferreira) [1]
> Notably, the term heat pump is more generic; it applies to many heating, ventilating and air conditioning (HVAC) devices used for space heating or cooling. When used for heating, a heat pump employs the same refrigeration-type cycle ...
"When used for heating" clearly indicates that the term is valid for both types of applications.
> And in either case the thermodynamics situation is simply the second law: it takes energy to do all that work, which turns into heat.
You better read up on what the second law means. What you write "takes energy .. which turns into heat" is actually linked to the first law.
> Sure, the energy from a fossil fuel was originally solar power, but that was millions of years ago. You can’t just magically claim its part of the current energy balance.
I am not making that case. The claim I am making, is that it doesn't matter for what kind of purpose you use this fossil energy (except for the weird uses I mentioned) because _all_ purposes will eventually turn it into heat.
Which is why I reject the claim that "AC heats up the planet". No, fossil energy use does, no matter what you use it for.
> The significant contribution of air conditioning to heat islands has been widely discussed for decades.
Your original claim was "AC heats up the planet though". Now you write "heat islands". Yeah, of course you have heat islands. I don't deny that. It's just something totally different from "heating up the planet". Because transferring heat from inside building to the surroundings doesn't change the planet's _thermal_ energy balance. It's the burning of fossil fuels that does so.
There are plenty who thinks that people who can't buy an air conditioner are lesser and don't deserve one. Bootstraps and all.
I like to look at the bigger picture, this will cause further instability in the world, which is bad for all of us. Besides the consumption of those who can afford an air conditioner drives climate change. You may be handing over the money in the shop, but it's the entire planet that subsidizes your purchase power, which is not cool, literally not cool.
Air conditioners nowadays can and should be bought as reversible heat pumps. It adds nothing to the purchase price and it replaces gas heating as a much more efficient way to heat a building.
We should be installing heat pumps everywhere. Power consumption may go up in summer but would go way down in winter as efficiency is greatly increased. Unless your point is that poor people don’t deserve heating any more than they deserve cooling…
Last I checked a heat pump is considerably more expensive than an air conditioner. And a regular air conditioner can probably only heat when the outside is not freezing.
I would actually want to get a heat pump but it's basically prohibitive. Would be nice to replace them with a "cheaper" air conditioner unit.
Hm, doesn't look marginal to me. A heat pump is like 5X-10x more costly and requires quite specialist install. An air conditioning unit is pretty easy to install by normal technicians.
> A heat pump is like 5X-10x more costly and requires quite specialist install.
When I shopped heat pumps, the actual unit was about 1.5x the cost of an equivalent air conditioner, and after installation the difference was even less.
> power consumption … would go way down in winter as efficiency is greatly increased
Not sure where you live, but in my experience living across the USA, I don’t think switching all heating to heat pumps in winter would reduce electricity usage. Most homes heat with propane, fuel oil, kerosene, or, in places like NYC, steam. There are certainly some homes out there with electric element heating but they are so expensive to run that they’re not very common.
It might be better for emissions if we used renewable energy to generate all of that power. But we don’t right now.
They are more than 100% efficient until you reach stupidly low temperatures; in which case, then you can break out the furnace or whatever. Or put on a blanket.
It does, but people do a good job at making a strawman of themselves. These bootstrap folks are out there, and they are here. And I'm not just talking about the libertarians, plenty of liberals have trouble seeing the bigger picture. When it's painful to do that, we don't do it. You don't need to live in Nazi Germany to be have to ignorant for your own good, cognitive biases like just-world fallacy are enough. Climate change is plenty enough, it creates a lot of uncertainty and it brings the strawman out of people. Our defense mechanisms are rather predictable.
Well, while their title alone leads to a "no shit, Sherlock?" response, because it's quite clear that it's hard to sleep in abnormally hot days (but there isn't anything there about the impact of global warming that it wants to push), that is really a data-mining study that found a correlation inside a huge amount of possible variables.
That means the study itself is a solid base for further examination, but meaningless for any real world conclusion.
They've identified several correlates due to weather (cloud cover, rain, wind, day length), but then I can't find where they correct for these in talking about effect sizes. All of these effects then "add up" to make the nearly 10-minute variation in sleep duration.
Also, sleep isn't only about duration - most sleep scientists would want to know about sleep efficiency too. This is "time asleep / time in bed". If you wake up more when it's cold, then there is a reason for shorter sleep when it's warm. Similarly, you'd ideally correct for air conditioning and factors like this on an individual level, but they don't seem to have this data.
Activity before bed, and the light that gets into your bedroom in the morning are certainly correlated with heat. It's important to investigate how these variables interact.
True. There are some parks with all kinds of exotic birds for human attraction. I get every time seeing all the projects lighting up the ponds and trees. Absolute madness.
And sound pollution, too. Fucking vehicles, man. I live in a busy city and in my estimates night traffic is at least 90% pleasure.
How do I know? Only idiots force their engines during the day, and at night I mostly hear idiots
this doesn't make much sense. It would mean people near the equator sleep worse or that someone used to the North moving to California will experience worse sleep. Sounds like p-hacking random study.
You ever toss and turn at night because it’s just too hot to sleep? Someone moving from the North to California would likely experience that. I know I did when I moved to Texas and my air conditioning unit broke down.
The authors say there is adaptation to the local climate so someone living near the equator might still get good sleep. The data is based on weather, and it checks out; it’s hard to sleep on a hot summer night.
I spent the first half of my life living 7 degrees south of the equator, in a city where temperatures in the hot season routinely go near 40o Celsius. I can tell first hand, it wrecks your sleep. Sleeping in a mattress is unbearable, even under low humidity and with a fan, your underside gets too hot, and the entire night is spent flipping in the bed. The only effective adaptation available to poor people, without AC, was to sleep in hammocks as a default. It avoids getting your underside too hot.
It'd hard to sleep for you not Africans. 1C difference can't make such a difference since we can adapt. I am all for climate change but the title of the study sounds meh.
It could be as simple as the relative change is one people aren't yet used to. If you grow up in 100 degree weather your whole life you get used to it. Probably there is some delta of time where we would adapt to any change in temp, but if the temp itself is constantly increasing then maybe our adaptation can't keep up as well
Idea: could this be an evolved trait? Could it be that sleeping less during hot weather was an evolutionary advantage?
Maybe spending more time asleep during the winter, presumably when food/resources are scarce, lowered energy needs and so increased survivability. In hot climates, predators are more active at night. Maybe our aversion to sleeping during hot nights evolved from a need to stay awake when the lions/tigers/bears were out looking to eat us? That could be why I find it easier to sleep out in the sun in the middle of a summer day (siesta) than I do at the same temperature during the night.
Dan Huberman, professor of neurobiology at Stanford, has some good info on sleep in his podcast and website, in case anyone just wants to learn a little more about sleep.
And move the whole city with you? Otherwise you will find yourself in the middle of nowhere with not much to do and not much to support you.
That's actually a big problem with global warming, maybe the biggest problem. Raising waters? Just move coastal cities on higher grounds. Some countries will actually benefit from global warming, I think that's the case for Canada, just move there.
But that's not how it works, you can't move around millions of people and hundreds of years worth of infrastructure just like that.
It’s nice data. They gave sleep tracking watches to 47,000 subjects for a few years, and this is what came out of it.
Their climate change angle is suspect. It probably helps publish to be relevant to a real-world problem. But their final paragraph undermines the projections they try to make: people adapt to the long-term weather patterns, and they’ll likely partially adapt to climate change occurring over the course of 50 years. Of course it’s still relevant from a health equity standpoint to consider.