
Improving air conditioner efficiency could reduce worldwide temps - aaronbrethorst
https://www.nytimes.com/interactive/2017/07/13/climate/climate-change-make-a-difference-quiz.html
======
djsumdog
So we curb emissions by building a bunch of new A/C units? Sorry, that's
silly.

CO2 is just one of many many forms of pollution. Think you're doing your part
by purchasing a hybrid or electric vehicle? There are barrels of oil that go
into those tiers, the plastics, not to mention all the pollution that goes
into battery production. If your car is fuel efficient, the best thing you can
do for the environment is drive it until the wheels fall off. When you do need
to purchase a replacement, get a used hybrid or electric.

Climate change/CO2 is not the problem. It's the symptom of rampant
consumerism. We can't buy and purchase our way out of destroying the planet.
We have to consume less, build cell phones that are upgradable and last a
decade instead of 2 ~ 3 years. Companies need to be praised for smaller
factories and lower sales for products that cost more and last longer.

That is a very very huge shift in the way we think. I'm not sure if it's even
remotely feasible or what it would take to convince people, industry, the
world to simply consume less.

~~~
hughw
Reducing the number of humans could be one approach. The idea causes rancorous
response from religious people who believe God told us to be fruitful and
multiply. To reduce births might require coercion, it's true, but it would not
require killing people or making them suffer. I don't see how else we can
continue to enjoy the benefits and power of technology while keeping the
planet habitable and enjoyable.

~~~
Berobero
You realize the world's birth rate has already been on the decline for
decades, correct? And in general, the bulk of this occurred not because of
coercion, but because of economic development and the ensuing shifts in
optimum family strategy.

~~~
esrauch
When you say "birth rate is falling" its effectively the second derivative on
"number of people" right? As in, if we have go from 2 children born per person
to 1.5 children born per person, we are still growing the number of people.

Even if "children per person" falls slow enough you could even indefinitely
_increase_ the rate that new people are added right?

~~~
hughw
I said children per family, not per person.

~~~
esrauch
I don't really understand the distinction: fewer children per family is the
same thing as fewer per person right? Like if you have 1.4 children per person
on average that means exactly 2.8 children per adult man + woman?

All I meant to point out is that "birth rate falling" doesn't map to
"population falling", if the average number of children per couple drops 2.5
to 2.1 then each generation is still larger (and the population still grows
exponentially).

~~~
hughw
Yeah, it has to fall below 1.0 child per person for the population to decline.
And it's commonly reported that is happening in developed countries.

------
clumsysmurf
Trump's 2018 budget zeroes funding for Energy Star, which among other things,
helps consumers pick the most efficient devices, save money in the long run.

What other ways can consumers compare the efficiency of A/C units? I would
think some standardized testing and labels would be required.

~~~
rplst8
There are standardized efficiency measurements that all A/C manufacturers must
conduct and publish in the US. You'll see terms like COP, EER, and SEER. Those
allow you to compare pretty easily.

Currently the minimum is a SEER of 13, but I've seen units as high as 22
advertised.

~~~
mjfern
A SEER 13-14 system can run $5-6K, while a SEER 22 system can cost upwards of
$15K (as a guesstimate). In theory, a SEER 22 system can pay for itself over
the long-term due to reduced electric/gas expenses. The issue is that higher
SEER systems, above 16 I believe, rely on variable speed motors. My
understanding is that they are inherently less reliable.

A SEER 13-16 system might last 15-20 years (if you're lucky), while a SEER 22
system could break down much earlier at about the 10 year mark. You can
sometimes replace specific parts, but depending on what breaks, it may not be
cost effective.

In short, the only way we're moving to more efficient AC systems is if costs
come down significantly, we see some major innovation in the field, or the
government provides significant financial incentives.

As an aside, I also think we could achieve energy efficiencies by increasing
the insulation in houses. It's unbelievable how much hot/cool air is lost
through windows, doors, crawl spaces, and attics.

~~~
EvanAnderson
I've had some major frustrations with poor reliability of the blower motor in
a 14 SEER HVAC system (installed in 2006) with a brushless DC motor. I've
replaced the motor 3 times in 10 years (conveniently failing shortly after the
warranty expired each time). Had I not done the work myself that would have
been between $600 and $800 per replacement.

Brushless / electronically commutated DC motors are pretty interesting,
though:
[https://en.wikipedia.org/wiki/Brushless_DC_electric_motor](https://en.wikipedia.org/wiki/Brushless_DC_electric_motor)

~~~
mjfern
Who's the manufacturer?

~~~
EvanAnderson
The air handler is a Bryant. The motors have been a General Electric X13 (the
original patent-holder for the X13 electronically commutated constant-torque
PWM motor controller), a Regal Beloit "Evergreen" X13 OEM replacement, and now
a Nidec X13 motor.

These motors are microcontroller-based. Apparently there was a rash of bad GE
X13 motors in the early 2000's traced to bad thermistors. Unfortunately the
board is potted in an insulating compound that makes board-level repair rather
impractical.

My first motor's controller failed after about 8 years. It was cheaper to just
buy a new motor vs. replacing only the controller. The second motor's rotor
started grinding against the stator after about 13 months. I pulled the
controller from that motor and installed it on the first motor (since it was
near-perfect duplicate of the original motor). That ran for 14 months before
the second controller failed.

I've been running the third (Nidec) motor for about 2 months. I'll be
interested to see how to holds up long-term.

------
cannonpr
I hate to say it but AC always felt like thoughtless engineering and
consumerism, especially the electric varieties. It's ironic that in a sunny,
energy rich environment, you spend extra energy on a heat pump. In a lot of
environments some better architecture will take care of the problem via
passive methods, additionally evaporative methods work pretty well in dry
environments and polute considerably less ? Failing that, hell atleast use
some solar energy to run the heat pumps locally, atleast stop burning stuff to
power them.

Failing all of the above, stoicism isn't that bad, honest, neither are life
style changes that shift high activity periods to later in the day, they are
widely practised in Mediterranean countries.

~~~
pdelbarba
Currently live in Colorado where the highs are regularly in the 90s. Turn the
house fan on at night for a couple hours, cool everything off, then close all
the doors and windows during the day and everything is perfectly comfortable.
When I lived in Philly however... 90% humidity and 80 degrees AT NIGHT is no
joke.

~~~
cannonpr
So to respond, yes I generally suggested the above for dry climates, I have
also lived in humid climates and agree to all the comments regarding them.
However I am willing to bet we use electrical heat pumps out of sheer
convenience even in climates that offer alternatives. That having been said,
even for humid environments, the ground often offers us solutions that are
more efficient. [https://en.wikipedia.org/wiki/Ground-
coupled_heat_exchanger](https://en.wikipedia.org/wiki/Ground-
coupled_heat_exchanger) They do however ofcourse require engineering and
support from society to adopt.

------
bradlys
> The Lawrence Berkeley study argues that even a 30 percent improvement in
> efficiency could avoid the peak load equivalent of about 1,500 power plants
> by 2030.

Okay, but where is this 30% jump in efficiency going to come from? That seems
like a pretty big leap!

~~~
klodolph
Off the top of my head,

* A lot of home conditioners are fighting the weather in conditions with poor insulation, running when nobody is home, or running in rooms when people are in different parts of the house.

* Office air conditioners are often set too cold, subjectively speaking, sometimes resulting in workers bringing sweaters or even space heaters to their desks. This is shockingly common. Multi-zone cooling can make things more uniform, and if you can get people to stop using space heaters during the summer, that can make a big difference. Gender is supposedly a huge factor in temperature preferences, and offices are set to men's cooler preferences. In some locations this is exacerbated by the fact that men wear suits and ties while the women wear skirts and weather-appropriate tops.

Personally, I want an air conditioner system that isn't set to a specific
temperature, but instead reduces the extreme temperatures outside. So instead
of keeping it set at 22 degrees, maybe it would be set to 22 degrees when it's
27 degrees out, but the AC goes to 25 degrees when it's 35 degrees out. I find
this more comfortable, because there's less of a shock when going outside or
coming inside.

~~~
JumpCrisscross
> _Gender is supposedly a huge factor in temperature preferences_

Source?

~~~
Eric_WVGG
[http://www.newyorker.com/tech/elements/is-your-thermostat-
se...](http://www.newyorker.com/tech/elements/is-your-thermostat-sexist)

The biological reasoning, as I understand it, is that men have a higher ratio
of heat-generating muscle than women.

When I first moved to NYC, I was bewildered by all the women walking around
with scarves and summer dresses; it was explained to me that this was a
strategy to optimize being comfortable in the outdoor heat, and then having
something to withstand the frigid offices.

(Personally, I'm of the opinion that one should acclimate to their climate,
and folks who hate the heat wouldn't mind it so much if they didn't coddle
themselves with AC all the time.)

~~~
khedoros1
> (Personally, I'm of the opinion that one should acclimate to their climate,
> and folks who hate the heat wouldn't mind it so much if they didn't coddle
> themselves with AC all the time.)

I agree, to an extent. I mean, bumping the temperature that you can be
comfortable in by 10 or 15 degrees is reasonable (up or down). I lived in
southern Arizona as a child, where 80 degree nights were heaven after 110
degree days. I'd argue that AC wasn't coddling there, though. "But it's a dry
heat" has special meaning for me. AC was usually set around 80 or 85.

During some of those same years, we stayed with family in my Grandparents'
house: 2 aging window ACs, 90 degree heat, 90% humidity. We spent most of our
time outside and slept in an un-conditioned room with the fan blasting. It's
doable, but not my preference. A few weeks certainly wasn't enough to
acclimate, and I think after a few years I'd probably still prefer to be in a
(somewhat) cooled room.

On the other hand, I lived somewhere cold during my early teens. The home was
often around 50 degrees with all the radiators blasting, and we dealt with
that too.

~~~
Eric_WVGG
same, I'm from Tucson. ^5

------
davidw
People in the US consume way too much air conditioning. It's pretty common
where I work for people to have sweaters to put on inside due to the AC.
Outside it's in the 80ies, with something like 10% humidity in the summer -
absolutely perfect unless you're doing hard labor in direct sunlight.

~~~
tomsthumb
While I agree that running the AC to to point of wearing a hoodie is
ridiculous, there are some pretty enormous chunks of the US where an 80 degree
summer day is relatively chilly, winds coming off of mountains or oceans are
basically nonexistent, and the humidity is super high.

~~~
davidw
Yeah (see my response to the guy from Munich) - but instead of cooling to 60F
or whatever, use the AC to dehumidify and cool off to, say, 80 or 78 or
something comfortable.

------
SilasX
... only if this doesn't temporarily bid down energy prices and lead others to
use the same energy somewhere else.

[https://en.wikipedia.org/wiki/Jevons_paradox](https://en.wikipedia.org/wiki/Jevons_paradox)

Note: the _more_ potential uses of a resources, the _more_ vulnerable it is to
Jevons effects, where people use a resource more in response to being able to
use it more efficiently.

The real benefit of energy efficiency is not that it reduces energy use by
itself, but that it reduces the _utility loss_ from implementing the caps and
taxes necessary to _actually_ reduce total usage.

------
rb808
Half the article wasn't about a/c efficiency it was that HFC is more of a
greenhouse gas than CO2, and was agreed to be phased out.

Is there really an HFC replacement - what is it? I wasnt aware.

~~~
strommen
Can't believe I had to scroll way down to find a comment that actually
understood the article!

There are new refrigerants called HFOs that are chemically-similar to HFCs,
but do not exhibit the greenhouse effect. Ammonia and propane also work, and
are commonly used in commercial refrigeration today.

------
SmellTheGlove
I have a Fujitsu mini split that has been awesome in terms of bringing my
electric bill down versus window units (we live in Maine, central A/C is less
common here, and few homes were built with it until the 2000's). It does, like
most splits, use R-410A, but I'd be happy to use something else if it didn't
kill the efficiency.

In parallel with refrigerants and efficiency, though, I wonder if the article
misses on mentioning geothermal cooling. Those systems are expensive, but if
you can bring down the install cost and power them with cleaner energy, you
solve some other problems. In developing nations, maybe you try and build
larger systems designed to cool multiple residential units - and start to
require it for mid/high-rise residential construction?

~~~
maxerickson
I'd want to see the energy calculations for highly insulated, well sealed
buildings. There is more material up front, but the insulation works during
the heating season too.

~~~
fastbeef
If you want to build a new house in Sweden you need to present an energy
calculation for the house so that you meet the fairly strict requirements.

Of the top of my head, a normal family house (150m2, 1-1/2 stories) is allowed
to consume between 5000-6500 kWh per year (low number in southern Sweden, same
as Denmark. High number northern Sweden above the polar circle).

This generally means >220mm insulation in walls and roof and >300mm insulation
in the foundation. In northern Sweden you need a geothermal pump to hit those
numbers.

------
Dangeranger
Could higher efficiency cooling be done by using more evaporative cooling
systems (Swamp Coolers)[0] rather than traditional AC units?

There are climates where evaporative cooling is not effective, but perhaps
they would be useful in the majority of climate regions.

[0]
[https://en.wikipedia.org/wiki/Evaporative_cooler](https://en.wikipedia.org/wiki/Evaporative_cooler)

~~~
jngreenlee
They can be very effective, they just look ugly and don't increase a house's
value.

[http://atomictoasters.com/wp-
content/uploads/2013/01/swamp-c...](http://atomictoasters.com/wp-
content/uploads/2013/01/swamp-cooler-1.jpg)

Authority: I live in Colorado.

~~~
SubiculumCode
and can even lead to mold

~~~
kchoudhu
This. American construction is mostly wood frame, making the possibility of
mold terrifying for any home owner.

~~~
peterwwillis
Improper installation of vapor barriers is much more likely to lead to mold.
If you don't inspect your contractor's work, expect problems.

------
adgqet
Misleading headline. Research found that the temperature increase could be
lowered by one degree centigrade.

~~~
rzzzt
The extra efficiency could be used to cool the outside air.

------
Element_
Toronto has a deep lake water cooling system that pumps cold water from the
bottom of Lake Ontario and circulates it around the downtown core. It is
capable of cooling 100 high-rise buildings. I believe when it was constructed
it was the largest system in North America.

[https://en.wikipedia.org/wiki/Enwave](https://en.wikipedia.org/wiki/Enwave)

~~~
contingencies
I'd never heard of these systems until reading this thread. I am frankly
amazed that China isn't using them. Here in Shenzhen (literally "deep bay")
alone I am certain this would save a lot of electricity.

------
johngalt
Large number of comments here acting like A/C is some wasteful extravagance,
or that people who live in warm climates should just move or 'get used to the
heat'.

I don't mean to spoil the moralizing fun here, but cooling uses less energy
than heating. So perhaps you should put on a sweater when it drops below
freezing where you live. You'll get used to it. Or you could move.

------
bcatanzaro
The planet would be better off if people moved out of the cold North and
instead used more air conditioning. That's because heating is incredibly
carbon intensive. Think about the temperature gradients in New York in the
winter time. Going from 20 or 30 degrees F to 70 degrees is more carbon
intensive than going from 90 degrees to 70 degrees, and the number of days
it's cold in the winter is often greater than the number of days it's hot in
the summer. The overall carbon burden of heating is greater than that of
cooling.

This means that the carbon angst directed at AC is primarily a puritanical
impulse. It's a new thing! It feels nice! So it must be a sin!

However, refrigerants are bad for climate because they have huge greenhouse
gas potential multipliers.

So the solution isn't really to improve air conditioner efficiency, it's
rather to find refrigerants with less warming potential.

And move everyone out of New York and Boston - their climate conditioning is
very carbon intensive.

------
dmritard96
One thing missing from this article is demand response:

"It matters, researchers say, because cooling has a direct relationship with
the building of coal-fired power plants to meet peak demand. If more air-
conditioners are humming in more homes and offices, then more capacity will be
required to meet the demand. So 1.6 billion new air-conditioners by 2050 means
thousands of new power plants will have to come on line to support them."

We [https://flair.co](https://flair.co) offer demand response tech for
minisplit control that can help prevent having to build all the 'peaker
plants'. This gets extra interesting when you add intermittent supply
(solar/wind) and grid tied storage (Tesla has been making big pushes here
among others). Hopefully, we are able to scale these up in parallel to prevent
a bunch of coal fired plants from being built for the 1-3% of the year with
the hottest days.

~~~
dv_dt
> "So 1.6 billion new air-conditioners by 2050 means thousands of new power
> plants will have to come on line to support them."

Or not, where California has brought enough solar power online to the point
that during peak times it has to pay to offload power to other states because
some natural gas operators can't (won't?) shutdown...

~~~
dmritard96
A big part is also demand response in California, for instance, why PG&E was
subsidizing smart thermostats. They can adjust all the setpoints and in
aggregate reduce the compressor cycling. to 'chop' the peak down on really hot
days.

------
pierrebeaucamp
I'm pretty disappointed in the numbers they chose for a vegetarian diet. It
feels to me as if they actively went ahead and picked to lowest values they
could find in their source. (Btw the source itself is a good read imo:
[http://www.drawdown.org/solutions/food/plant-rich-
diet](http://www.drawdown.org/solutions/food/plant-rich-diet))

You could argue that people are not willing to go vegetarian or even vegan -
but at least level the numbers when comparing it with other solutions: If
everyone would go vegetarian, their source states 132 gigatons of CO2
reductions.

I also liked this quote from the report:

> As Zen master Thich Nhat Hanh has said, making the transition to a plant-
> based diet may be the most effective way an individual can stop climate
> change.

~~~
beambot
Better, balanced diets also create positive feedback loops in the healthcare
equation too -- especially for low income homes. Like many things, it is a
human psychology and behavioral challenge...

~~~
npsimons
> Better, balanced diets also create positive feedback loops in the healthcare
> equation too

You can still eat your way to obesity on a vegan diet - oreos are vegan, after
all. Considering that the obesity epidemic is currently the number one driver
for health care costs in USA, and it's only expected to get worse
([http://dailybruin.com/2011/10/26/obesity_has_become_an_overs...](http://dailybruin.com/2011/10/26/obesity_has_become_an_oversized_problem_in_the_u-s/)),
we could probably vastly reduce costs (and therefore emissions) by just eating
a little less, vegan or no.

Edit: why the downvotes?

~~~
beambot
Best rules I ever saw: (1) Eat "food", not processed crap; (2) not too much;
(3) mostly plants.

------
EGreg
Not for nothing, but ain't greenhouse gases only the short term problem?

The Earth radiates a fixed amount of energy into space every year. But when we
produce electricity etc. no matter how we do it, more than half of the energy
escapes as heat - a byproduct of boiling the water or whatever!

This isn't sustainable in the long run either! We are basically raising the
temperature of the atmosphere even without greenhouse gases.

Tell me where I'm going wrong:

[https://dothemath.ucsd.edu/2012/04/economist-meets-
physicist...](https://dothemath.ucsd.edu/2012/04/economist-meets-physicist/)

[https://dothemath.ucsd.edu/2011/10/why-not-
space/](https://dothemath.ucsd.edu/2011/10/why-not-space/)

~~~
maxerickson
The slightly warmer planet cools off faster (Newton's law of cooling). The
heat doesn't just statically build up over time.

As long as we still have cold seasons, it is safe to assume that solar inputs
are dominating our own.

~~~
comicjk
Newton's law is for convection of heat into the air. The cooling of the earth
happens by radiation into vacuum, so it's actually much MORE temperature-
sensitive: the heat radiated is proportional to the fourth power of the
temperature.

[https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law](https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law)

~~~
maxerickson
Thanks for the correction.

------
pdelbarba
I'm a little confused why solar isn't mentioned. Peak temperature and peak
solar flux are highly correlated so this isn't some weird grid storage
problem. Tighten standards for new systems and construction to be a little
more efficient and let economics go to work.

------
quadrangle
We already have solutions for dramatically more effective conditioning of
indoors. Simply do other effective things to cool the indoors. Modern
insulated whole-house fans like Airscape, exterior shades, etc. see
[http://www.treehugger.com/sustainable-product-
design/10-over...](http://www.treehugger.com/sustainable-product-
design/10-overlooked-low-tech-ways-of-keeping-your-home-cool.html)

The efficiency focus is itself misguided in several ways.
[http://freakonomics.com/podcast/how-efficient-is-energy-
effi...](http://freakonomics.com/podcast/how-efficient-is-energy-efficiency-a-
new-freakonomics-radio-podcast/)

------
zackmorris
One of the most wasteful components is the condenser. Salt water air
conditioners can accomplish the same thing much more easily (50-75% savings):

[http://www.happonomy.org/get-inspired/salt-water-air-
conditi...](http://www.happonomy.org/get-inspired/salt-water-air-
conditioners.html)

[https://www.cnet.com/news/salt-driven-air-conditioner-
looks-...](https://www.cnet.com/news/salt-driven-air-conditioner-looks-to-
slash-energy/)

This is very old technology so people probably chose aesthetics over cost.
Although when I think tacky, I think window air conditioning units..

------
PhantomGremlin
We need a corresponding article telling us how many power plants we can avoid
building by not mining Bitcoin. I love the general idea of cyber currency /
bitcoin / block chain, but I hate that the implementation requires so much
energy.

------
grogenaut
If we bumped efficiency 30%, how many more people would run the AC 30% more?

------
clenfest
In this house we obey the laws of thermodynamics!

------
thomk
Slightly offtopic but I just had a new HVAC system put in my house and one of
the things the tech pointed out to me is that effective AC has a lot to do
with effective dehumidifying.

I don't know why it never crossed my mind before but now when I transition
from indoors to outdoors (and back) I notice the humidity delta as much as the
temperature delta.

------
uses
It's funny how almost without fail on HN, I can go to the comments, and the
#1-5 comments is someone who quickly dismisses the main premise of the linked
article. It's ridiculous how common this is. I've been reading HN over a
decade and I don't remember if it was always like this?

------
afinlayson
Air conditioners are really inefficient, and people run them in excess. And
because there's no carbon tax, the cost of them is too cheap to curb usage.
Sure it won't solve the whole problem, but solving this issue would be very
valuable to the planet.

------
kylehotchkiss
Wouldn't switching to DC motors for both the fan and the compressor save a lot
of power?

~~~
jngreenlee
Not the source of significance, according to the article:

"New research from the Lawrence Berkeley National Laboratory in California
indicates that adding improved efficiency in refrigeration and phasing out
fluorinated gases used for cooling, as mandated by international agreement,
could eliminate a full degree Celsius of warming by 2100. Given that the
“business as usual” trajectory leads to 4 to 5 degrees Celsius of warming,
that is shaving off a pretty big slice.

Hydrofluorocarbons, or HFCs, account for about 1 percent of global greenhouse
gas emissions, but they can be thousands of times as potent than carbon
dioxide "

------
Mz
Passive solar and vernacular architecture makes vastly more sense. I get so
tired of these schemes to make our broken lifestyles "more efficient." Just
adopt a better method entirely and quit quibbling about tiny efficiency gains.

~~~
ch4s3
You're saying that as though passively cooled architecture has no drawbacks in
terms of cost, structural integrity, versatility, or suitability for building
dense living spaces. I doubt we can develop large cities in the future without
a serious focus on improved HVAC. Sure, passive methods, geothermal
heating/cooling, etc will have a place, but they certainly aren't the only
path forward.

For example, how would you passively control humidity. It's 89F and 55%
humidity where I'm sitting right now, outside airflow feels like wet hot
death.

~~~
Mz
I don't know what country you are from, but I am saying that as an American
who has lived in Germany and has studied this problem space some at the
college level. Most American homes are terrible cardboard boxes. German
apartments routinely have thicker walls, fewer windows and other interruptions
in the wall space and the windows are more useful than American ones. It was
common when I was there for windows to have two ways to be opened, one just
for airflow that was not a security risk and one to allow it to open
completely, like a door. They typically had no screens.

There is zero reason why American housing cannot incorporate, as a minimum,
more thermal mass -- like German apartments routinely do.

Furthermore, many American cities are simply not that dense. There are few
places in the U.S. that are really densely urban with lots of skyscrapers. So
most passive solar methods would be applicable for most structures here.

I grew up in the Deep South, where 98F was quite common in the summer, with
much higher humidity than 55%, and I have lived in the High Desert, where I
did my long walks for exercise (up to 6 miles) after the sun set so temps
would drop to a cool 99F. The temperature and humidity you list does not
qualify in my book as "wet, hot death" and I see zero reason that a building
could not be made reasonably comfortable in such conditions using mostly
passive techniques.

------
axelfontaine
American air conditioners running at full power, chilling the interior and
dripping on the sidewalk below on a hot day always deeply trouble me. Maybe
it's my european view on things, but for contrast here in Munich we aren't
just building out a city-wide heat network, but we also have a cold network!
Cold river water flows through the pipe network that traverses the city and
large office building can get connected to it. This way they can save
massively on electricity for air conditioning by having the water do the
cooling instead. And then once the water has traversed all pipes, it simply
gets released back into its stream on the other end of town, just as clean as
when it entered, and only slightly warmer.

~~~
jriot
Berlin doesn't nearly get as hot as the United States. Try sitting inside a
house in Mobile, AL in July without air conditioner and see how long you last.
Using your water example, what about the deserts in the US that don't have a
nearby water source to cool everything. Europe is much cooler in comparison to
the US.

~~~
tbihl
I agree with most of what you've said, but I'd also argue that having large
groups living out in the desert is such an absurd configuration for humans
that it presupposes an indifference for any sort of sustainability.

~~~
jachee
> an indifference for any sort of sustainability.

That's a pretty apt general description of Las Vegas.

~~~
pilom
I would actually put Vegas as one of the most sustainable cities in the US out
of necessity. Vegas's per capita water use is about 1/4 of the US average
including all of those crazy fountains on the strip. They don't irrigate
anything compared to places like Phoenix and almost all municipal water
hookups use reclaimed water unlike most other cities where people have an
aversion to drinking filtered piss. Vegas also gets almost all of its energy
from renewable sources (hydro and a tiny amount of solar) compared to the US
as a whole which is only about 10%. Colorado by comparison gets about 60% of
it's electricity from coal.

~~~
jachee
Fair enough. Consider me educated. It was a quick jab with only an outsider's
superficial perspective.

    
    
        s/Las Vegas/Phoenix

------
petre
Using a white roof and employing other passive coolong techniques could
improve AC efficiency, or even make it redundant.

------
maxxxxx
Just insulate the houses in the US. I am always shocked how badly built US
houses that cost 600k are.

~~~
rplst8
Good insulation is pretty standard here in the US for everything built in the
last two decades or so.

That said, fiberglass insulation mostly only helps against convection
cooling/heating. I.e. through the movement of air. Summertime heat is mostly
conductive and radiative i.e. near infrared. Insulation doesn't do much to
stop that.

Shade trees however help this big time. A large tree placed in the right spot
to shade a house in the afternoon can replace as many as seven window air
conditioner units.

~~~
astrodust
If anything they're over-insulated which can create other problems like a lack
of fresh air, mold and fungus problems, and poor air quality in general.

The more you insulate the more you need to ensure you have proper ventilation,
which is a sort of paradox.

~~~
maxxxxx
You can insulate properly and still have air flow. It's not that hard.

------
return0
let's just build a giant A/C and put the external unit on the moon

------
jwilk
Wrong symbol in the title:

º = ordinal indicator

° = degree

~~~
LeifCarrotson
Two questions:

1\. How did you notice this?

2\. Why does it matter, or when would I want to use one instead of the other
for reasons other than being technically correct?

~~~
jwilk
They look different in my font:
[https://i.imgur.com/gjTkaa6.png](https://i.imgur.com/gjTkaa6.png)

~~~
LeifCarrotson
Ah. Practically identical in mine:

[http://i.imgur.com/3YcxWIy.png](http://i.imgur.com/3YcxWIy.png)

------
Zarath
Open a damn window. I'm sure in some places AC is necessary, but way too often
I hear/see people running it when there is absolutely no reason other than
they are even mildly uncomfortable.

Seriously, this problem isn't going to be fixed until people actually pay the
true cost of what they are doing: Electricity + Global Warming externalities.

------
33W
[SPOILER ALERT]

Can we change the post title to match the article?

"If You Fix This, You Fix a Big Piece of the Climate Puzzle"

~~~
AnimalMuppet
I much prefer my post titles to be spoilers, rather than clickbait. I waste
less of my life that way.

