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Improving air conditioner efficiency could reduce worldwide temps

nytimes.com

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Re: Improving air conditioner efficiency could reduce worldwide temps

#261

Post by vacri »

jriot wrote: post #82
axelfontaine wrote: post #64

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 t…

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.

Air conditioning also changes humidity, not just temperature. I imagine few cities in Germany are particularly humid.

Re: Improving air conditioner efficiency could reduce worldwide temps

#262

Post by curun1r »

mannykannot wrote: post #75
klodolph wrote: post #24

Earlier quoted context omitted.

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 ca…

Ceiling fans reduce the need for AC, especially overnight - even gentle circulation makes a noticeable difference. Also, an attic fan that can blow cool overnight air through the building whenever the temperature and humidity outside are acceptably low might reduce the expenditure of AC on cooling down the structure. A small degree of automation would allow these measures to work together with the AC.

I spent much of last year traveling around Southeast Asia and I always opted for fan rooms over A/C whenever possible. Yes, they were warmer, but once you got used to it, it wasn't a problem. But the best part about it was the lack of the respiratory problems that went along with A/C. In humid environments like the tropics, going between wet air and dry air can be really rough on the sinuses.

I wonder how many people have respiratory problems that they chalk up to allergies and whatnot that are actually due to the breathing overly-dry A/C air.

Re: Improving air conditioner efficiency could reduce worldwide temps

#263

Post by beambot »

npsimons wrote: post #132
beambot wrote: post #57

Earlier quoted context omitted.

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...

> 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... ), we could probably vastly reduce cost…

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

Re: Improving air conditioner efficiency could reduce worldwide temps

#264

Post by lossolo »

crush-n-spread wrote: post #250
lossolo wrote: post #246

Earlier quoted context omitted.

Actually livestock farming produces from 20% to 50% of all man-made greenhouse gas emissions.

Hi, I was wondering if you have any concrete data for this? I don't think it's true but I'll believe it if I can see some studies or data on it.

Sure, you can check this:

http://www.worldwatch.org/files/pdf/Livestock%20and%20Climat...

Re: Improving air conditioner efficiency could reduce worldwide temps

#266

Post by dpark »

WalterBright wrote: post #174
thescriptkiddie wrote: post #154

Earlier quoted context omitted.

A large part of this could be mitigated by building with passive thermal efficiency in mind. Features like extra insulation on roofs and south facing walls, large thermal masses, strategic eaves that block sunlight in the summer but let it through in the winter, whole building energy recovery ventilation systems, green roofs, underground living spaces, etc.

Simply using a white coating on the roof can reduce the A/C bill by about 3%. It's so simple, I do not know why this isn't part of the building code in hot places. People may not like it for their homes, but for commercial buildings with flat roofs, it's a no-brainer.

Don't most commercial buildings use white roofs? I've not spent a lot of time on commercial roofs, but the ones I've been on were always white.

Re: Improving air conditioner efficiency could reduce worldwide temps

#267

Post by cestith »

mjfern wrote: post #90
rplst8 wrote: post #46

Earlier quoted context omitted.

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.

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), w…

Unless it raises the resale value of the home reliably, long-term payback is of little motivational value without job security or significant money in reserve. That's one of the uncomfortable microeconomic truths driving short-term decision making in things like cooling, solar power, and battery systems. Why would someone take out a loan or tie up a large portion of their liquid capital to see a ten-year payback on a house they might be forced to sell next month?

With 2008 not being so long ago, neither job security nor resale value are that promising. We're still rebuilding consumer confidence after nine years. The economic recovery in the US is largely in a handful of major metropolitan areas pulling up the averages, with large swathes of the country still struggling. This needs to improve or some government incentive program like you mention must take it into account if we're going to sell capital-intensive home upgrades.

Re: Improving air conditioner efficiency could reduce worldwide temps

#268

Post by nostromo »

QuarterReptile wrote: post #94
jriot wrote: post #82

Earlier quoted context omitted.

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.

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.

Better to put people in the desert than in places where they displace a lot of existing biodiversity (like, say, all of our coastal cities).

Re: Improving air conditioner efficiency could reduce worldwide temps

#269

Post by putsteadywere »

coredog64 wrote: post #200
QuarterReptile wrote: post #94

Earlier quoted context omitted.

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.

You may find this hard to believe, but moving heat around (i.e. air conditioning) is more energy efficient than straight up heating. It is more environmentally friendly when you consider that in many cold locales in the US, heat is provided not by electricity, but by a shitload of on-site oil-fired devices.

I googled this, because I did find it hard to believe, and I think you're correct. According to the below source, for example, heating a home in Atlanta, Georgia throughout the winter months costs about twice as much as air conditioning it in the summer months.

[0]: http://www.energyvanguard.com/blog/30576/Heating-or-Cooling-...

Re: Improving air conditioner efficiency could reduce worldwide temps

#270

Post by pilom »

jachee wrote: post #114
QuarterReptile wrote: post #94

Earlier quoted context omitted.

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.

> an indifference for any sort of sustainability. That's a pretty apt general description of Las Vegas.

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.
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