Improving air conditioner efficiency could reduce worldwide temps • Hacker News Board

Re: Improving air conditioner efficiency could reduce worldwide temps

#51

Post by SilasX » Thu, Jul 13, 2017, 8:24 PM UTC

... 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

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.

Re: Improving air conditioner efficiency could reduce worldwide temps

#52

Post by mperham » Thu, Jul 13, 2017, 8:27 PM UTC

JumpCrisscross wrote: post #40

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…

> Gender is supposedly a huge factor in temperature preferences Source?

Every (hetero) marriage.

Re: Improving air conditioner efficiency could reduce worldwide temps

#53

Post by thehardsphere » Thu, Jul 13, 2017, 8:27 PM UTC

24gttghh wrote: post #50

thehardsphere wrote: post #48

Earlier quoted context omitted.

Fortunately, the actual spending decisions are made by Congress, so the content of the President's proposed budget doesn't matter.

Fortunately? Congress is a bit of a double-edged sword in that regard...

Quite true. But if you are concerned about the EnergyStar cuts, it is fortunate because they are not likely to happen.

Re: Improving air conditioner efficiency could reduce worldwide temps

#54

Post by dangrossman » Thu, Jul 13, 2017, 8:28 PM UTC

JumpCrisscross wrote: post #40

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…

> Gender is supposedly a huge factor in temperature preferences Source?

"In this study gender differences in thermal comfort and use of thermostats were examined by a quantitative interview survey with a total of 3094 respondents, and by controlled experiments. The studies were carried out in Finland and considered everyday thermal environments: homes, offices and a university. The results show significant gender differences in thermal comfort, temperature preference, and use of thermostats. Females are less satisfied with room temperatures than males, prefer higher room temperatures than males, and feel both uncomfortably cold and uncomfortably hot more often than males."

"Gender differences in thermal comfort and use of thermostats in everyday thermal environments". Building and Environment, Volume 42, Issue 4, April 2007, Pages 1594-1603

Re: Improving air conditioner efficiency could reduce worldwide temps

#55

Post by DiabloD3 » Thu, Jul 13, 2017, 8:28 PM UTC

Nition wrote: post #49

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…

Also, people who set their home heat pump to "auto" instead of "heat" in winter and "cool" in summer. No-one should mind if they have it on 18 in winter and the sun heats the room to 20 in the afternoon, but a heat pump on auto will start cooling to maintain the room at 18.

I also agree, if you have a heat pump do not use auto mode, it will never do what you actually want.

Re: Improving air conditioner efficiency could reduce worldwide temps

#56

Post by comicjk » Thu, Jul 13, 2017, 8:28 PM UTC

maxerickson wrote: post #22

EGreg wrote: post #13

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 greenho…

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.

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

Re: Improving air conditioner efficiency could reduce worldwide temps

#57

Post by beambot » Thu, Jul 13, 2017, 8:29 PM UTC

pierrebeaucamp wrote: post #44

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 ) 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 sol…

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...

Re: Improving air conditioner efficiency could reduce worldwide temps

#58

Post by a_t48 » Thu, Jul 13, 2017, 8:29 PM UTC

rplst8 wrote: post #46

clumsysmurf wrote: post #23

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.

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.

Higher is better in this case?

Re: Improving air conditioner efficiency could reduce worldwide temps

#59

Post by tasty_freeze » Thu, Jul 13, 2017, 8:30 PM UTC

maxerickson wrote: post #22

EGreg wrote: post #13

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 greenho…

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.

Obviously solar input dominate over whatever energy we add through burning fossil fuels. Nobody contests that. You must have heard of the greenhouse effect. THAT is the issue. By changing the composition of the atmosphere, a fractionally greater percentage of the astounding amount of energy is reflected back to the earth instead of escaping into the atmosphere, raising the temperature of the atmosphere and oceans.

Imagine sitting in the sun on a warm but not hot day. Now imagine you are sitting in a car in the same spot in the same conditions with the windows rolled up. There is no extra energy being released, just the plain old sun, but the temperature you experience is going to be much higher. Indeed, the temperature increase doesn't grow without bound, but it is meaningfully higher.

Re: Improving air conditioner efficiency could reduce worldwide temps

#60

Post by LeifCarrotson » Thu, Jul 13, 2017, 8:32 PM UTC

RcouF1uZ4gsC wrote: post #39

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…

The issue in cooling preferences is that if it is too cold, people can wear sweaters or even bring space heaters. If it is too hot, there is not much you can do. I think this problem is exacerbated by open office plans. If you have private/semi-private offices, you can probably do a much better job of controlling local temperature.

We have private offices, but central HVAC. Multi-zone cooling (independent of having lots of little, less efficient window/through-wall units) is relatively uncommon.

It's exacerbated (good word) by the fact that the large front office has mostly women sitting at low-power PCs, the offices are mostly men at powerful workstations (aka space heaters), and the HVAC ducts run though the office drop ceilings, meaning anyone doing physical projects in the central work space is the least cooled while our receptionist has been seen with a space heater.