
The air conditioning trap: how cold air is heating the world - axiomdata316
https://www.theguardian.com/environment/2019/aug/29/the-air-conditioning-trap-how-cold-air-is-heating-the-world
======
jefftk
This is completely backwards. In the US air conditioning has facilitated
people moving from colder to warmer areas, which decreases energy usage. Yes,
you don't need AC in the Northeast but you need a lot of heat, so people
moving to the Sunbelt reduces carbon emissions.

Outside the US, this ignores how much happier and more productive people are
when they're not overheated. Traditionally cold areas have been much more
productive than warm areas, but AC could change this.

~~~
bromuro
Oh I was absolutely not happier or more productive while living in the US. Air
conditioning there was driving me insane and it had bad effects on my health
too.

It is unhealthy for sure: my flatmate coming back from jogging sweating and
all... first thing he does, turn AC on.

It was also sad to see AC running day and night and reading news about climate
change the same time.

~~~
Arbalest
Your final point misses the parent's point completely. Yes it uses energy, but
cold areas use more. It might also be worth mentioning that the use of boilers
may be dirtier than going through a centralised burner, as the economies of
scale would favour efficiency improvements at large scale more than at small,
building scale.

As for being unhealthy, that's an issue of dry, circulating air. This would be
addressed better with radiative cooling and potentially humidity control. Some
cleaning out of air filters may also be due.

edit: Oh and of course, building regulations (and enforcement thereof) and
insulation shouldn't be forgotten, like I just did.

------
rayiner
Contrast: [https://www.vox.com/2015/3/23/8278085/singapore-lee-kuan-
yew...](https://www.vox.com/2015/3/23/8278085/singapore-lee-kuan-yew-air-
conditioning)

According to Singapore’s first prime minister:

> Air conditioning was a most important invention for us, perhaps one of the
> signal inventions of history. It changed the nature of civilization by
> making development possible in the tropics.

> Without air conditioning you can work only in the cool early-morning hours
> or at dusk. The first thing I did upon becoming prime minister was to
> install air conditioners in buildings where the civil service worked. This
> was key to public efficiency.

~~~
drak0n1c
AC also uses significantly less electricity and fossil fuels than Heating
during the winter.

~~~
ljf
Sounds interesting - do you have a source for that? I guess that would be
country /location specific? Here in the UK most people use zero energy for
aircon, and loads fo heating - but I'm sure in most of the world this would be
inverse.

~~~
drak0n1c
Here's a breakdown from 2007:
[https://www.npr.org/templates/story/story.php?storyId=139417...](https://www.npr.org/templates/story/story.php?storyId=13941744)

More in-depth analysis:
[http://www.energysolutionscenter.org/assets/1/Page/GHP_Posit...](http://www.energysolutionscenter.org/assets/1/Page/GHP_Position_Paper_and_apndx_031710.pdf)

In general, it appears that it's slightly better for carbon emissions to live
in a warmer area with regular AC than it is to live in a humid temperate area
that requires both heat half the year and AC the other half, or a cold area
that requires heat most of the year.

~~~
fuzzfactor
According to Figure 2 of the GHP paper that must be why Daytona would be
preferable to Birmingham or Dallas if you wanted to minimize overall energy
use by focusing on AC alone, using little or none during the warmer months.

A basic rule of thumb is that it takes enough natural gas to heat three homes
in order to produce the electricity to heat only one home.

Also that it takes about 3kWh of electricity for an AC unit to cool off the
heat produced by 1kWh of electrical appliances or other heat sources.

------
geff82
Always remember that the Persians in Iran have had air conditioning for over
1000 years now, in a really hot place, completely sustainable. It might not
make rooms freezing cold as it is possible today, but it works. It is called a
"badgir".
[https://en.wikipedia.org/wiki/Windcatcher](https://en.wikipedia.org/wiki/Windcatcher)

I am sure we can learn from them and maybe develop that idea further.

~~~
hwillis
"Completely sustainable" is a _technically_ true but only for a fairly low
(<20%) percentage of locations. It's just evaporative cooling, so it relies on
a large water supply. It also increases local humidity significantly so it can
make the outside environment even more uncomfortable much more quickly than
normal air conditioning. It's also more expensive anywhere water isn't
essentially free.

That said it's great in places like India and southeast Asia, where huge
numbers of people live.

~~~
jdmichal
Those are sometimes called swamp coolers in slang, and are pretty common in
the US where it's dry enough to be effective. But that pretty much excludes
the entire east coast and Gulf areas.

------
mc32
We may be able to minimize air conditioning in most of North America (and
other temperate regions) with some modification of buildings and green
approaches.

The architectural approach is not a solution in the tropics and desert areas.
Just ask Lee, Kwan Yew. It’s a necessity in a modern society in the tropics.

~~~
doctorpangloss
Yes, when it comes to the tradeoffs of global warming, the leadership of an
oil economy that imports most of its goods is the best source of information.

~~~
rayiner
I’d say that conservationist-environmentalists just want us south Asians to
remain poor and backwards, denying as they do the importance of air
conditioning, large-scale industrial agriculture, and GMOs. That might give
them too much credit for having thought through things, however.

------
Simulacra
This article misses the important point of <i>moving</> air. We live in
Washington, DC in a one hundred year old house, and our air conditioning
doesn't get used much. What DOES get used a lot is the fan in our HVAC. We
chose a very powerful system to MOVE that air around, and keep a constant
breeze going through the house. This has kept it nice and comfortable without
having to rely on the a/c. We also installed multiple, powerful fans in the
attic that automatically turn on to exhaust air, pulling it up from the lower
flowers so cooler air can sink. So all this to say, it's not just the a/c that
keeps a home cooler.

------
jonatron
_13,400MW every second_ Clearly nobody checked this article.

~~~
mc32
But that’s against the average of 10GW, so that’s 3GW diff. Still a lot, but
not what you’re listing.

~~~
ggreer
A megawatt is a million joules per second. It’s a unit of power, not energy.

Mixing up watts and joules is like mixing up miles and miles per hour. It
demonstrates a fundamental misunderstanding.

------
hwillis
AC is _still_ a status signal, even outside the American south- when was the
last time you were at a movie theater or a bank that wasn't colder than it
needed to be, even uncomfortably so? It's traditional of places that try to
impress luxury.

Honestly, while the power use is a problem, I don't think it's the most
important AC-related problem. It's relatively small compared to _all_
electricity, and is fixed with renewable power, unlike current heating
solutions. Since AC just moves heat around, it causes significant localized
heating in cities.

There is a neat idea to solve that, though. Beam that heat right into
space[1]! The principle is similar to the radiators that keep the ISS cool-
since thermal radiation happens at a different wavelength from sunlight, you
can make a material that is "white" (reflective) to sunlight but also "black"
(radiative) to infrared radiation. Unfortunately thermodynamics puts a strong
limit on this; for a given area you need to make the radiator hotter[2] to
give off more radiation, but that makes the refrigeration cycle much less
efficient. Buildings need to become much greener than they are already
becoming.

[1]: [https://phys.org/news/2018-10-energy-saving-radiative-
coolin...](https://phys.org/news/2018-10-energy-saving-radiative-cooling-
ready-real-world.html)

[2]: ie surround it in insulation that is transparent to infrared. That keeps
the air from heating up but allows heat to escape to the sky. Trickier than it
sounds, though- glass and some plastics are opaque to many kinds of infrared.

~~~
bsder
> when was the last time you were at a movie theater or a bank that wasn't
> colder than it needed to be, even uncomfortably so?

This is a problem of thermal mass that changes suddenly.

Every human is roughly 100W of heat. You need roughly 10KW of dissipation per
hundred people. If you suddenly add a couple hundred people to a temperature
controlled room, you need a bunch of extra AC overcapacity, and people are
going to start to complain if you don't have enough overcapacity to prevent
that temperature from rising within a couple of minutes.

Then you have the flip side--a couple hundred people _leave_ the theatre. Your
AC suddenly is overproducing cooling that it doesn't need, and your theatre
may have a little bit of insulation to try to cut down on your AC costs. So,
you undershoot the temperature and then the insulation keeps it there as you
don't have 30-50KW of heat producing humans to bring it back up.

~~~
rahimnathwani
"Then you have the flip side--a couple hundred people leave the theatre."

But those people don't leave a vacuum. They are replaced with air from
outside, which is hotter than the cooled air inside. Sure, you need to set the
thermostat to a lower temperature than desired before the movie starts. But,
once everyone is has taken their seats, you can set it to 25C or whatever.
When the people leave and the hot air from outside replaces them, the AC will
turn off and there won't be anything to force the temperature down below 25C.
Am I wrong?

~~~
bsder
> They are replaced with air from outside, which is hotter than the cooled air
> inside.

That would actually make the response _worse_ , not better.

Let's assume the AC is at steady state. It is pumping 30KW of heat energy out
in order to maintain constant temperature. If everybody leaves and hot air
comes in, the temperature _rises_ and the AC system thinks "Temperature went
up, I need to pump _even more_ energy out."

The temperature needs to _fall_ before the AC system starts backing off.
However, by the time the temperature actually falls, the "velocity" of the
temperature movement will cause the system to undershoot the target
temperature.

This is a control systems problem. You can avoid over/undershoot (which a few
people will complain about), but then you give up response time (which _lots_
of people will complain about).

------
riffraff
I've resisted installing an AC in my apartment for the last few years, even
though temperatures have been over 30° very often during the summer.

Sadly, I work from home, and using a computer makes the heat worse, and
working with a scalding object in a very hot environment lowers productivity
terribly, and it doesn't seem like computers are getting cooler.

~~~
bromuro
Have you tried with a fan or some cold showers? I also work remotely and often
in tropical climates.

------
hadlock
I did the math once, it takes about 3 watts of energy to remove one watt of
energy (heat) from an average house in Texas when it's over 95F (35C) outside
using a typical air conditioner.

~~~
jdmichal
That would be a COP of 1/3, or a EER of about 1. I'm going to assert that you
probably messed up your math somewhere, seeing as an EER of around 11 at 95°F
is pretty common. (And also represents roughly the _minimum_ required
efficiency of an A/C sold in Texas since 2006.)

~~~
hwillis
Second- 1/3 is about what you'd expect for a Peltier module at a similar
temperature difference.

