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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

#41

Post by mtgentry »

bradlys wrote: post #18

> 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!

I spoke with an HVAC guy over the weekend about just this topic. He said about 4 yrs ago, the state of CA required all new construction to have ducting that goes to and from, each room in a house. So when Jr. goes off to college, you can close the door and not send cool air to his room. I think he said it's something like 30% more efficient? But don't quote me on that.

Re: Improving air conditioner efficiency could reduce worldwide temps

#42

Post by rplst8 »

bradlys wrote: post #18

> 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!

Well, the efficiency of a heat pump/refrigerator is limited by Carnot's theorem. Essentially it boils down to the difference of the outside temperature compared to inside temperature. With an indoor temp of ~72F and outdoor ~90F the maximum efficiency is a COP of about 30. Current AC units are in the 2 to 4 range. So a 30% increase doesn't seem impossible that low on the efficiency scale. There was a recent similar jump in efficiency when the US raised the minimum SEER standards for new systems from 10 to 13.

Re: Improving air conditioner efficiency could reduce worldwide temps

#43

Post by 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.

Re: Improving air conditioner efficiency could reduce worldwide temps

#44

Post by 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)

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.

Re: Improving air conditioner efficiency could reduce worldwide temps

#45

Post by RcouF1uZ4gsC »

sandover wrote: post #38
bradlys wrote: post #18

> 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!

If you're in the US, you can likely save much more than 30% today by replacing a central air system with a ductless mini-split style system. These are already dominant in the rest of the world, however.

I actually saw an installation in a new apartment. After seeing that, I much preferred central AC. One of the nice things about the US style central AC systems, is that the bathrooms are comfortable. In the split style system, a few rooms (bedrooms/living room) may be comfortable but other rooms (such as bathrooms) are miserably stuffy.

Re: Improving air conditioner efficiency could reduce worldwide temps

#46

Post by rplst8 »

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.

Re: Improving air conditioner efficiency could reduce worldwide temps

#47

Post by jrs235 »

klodolph wrote: post #24
bradlys wrote: post #18

> 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!

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…

All the more reason we need to find a way to make remote work work for positions and jobs that allow it. Most people are already heating and cooling their homes while away at the office. How much energy can we save and how much more comfortable can we be if we work from our homes? Additionally less energy is consumed and less pollution generated from not having to commute.

Re: Improving air conditioner efficiency could reduce worldwide temps

#48

Post by thehardsphere »

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.

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

Re: Improving air conditioner efficiency could reduce worldwide temps

#49

Post by Nition »

klodolph wrote: post #24
bradlys wrote: post #18

> 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!

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.

Re: Improving air conditioner efficiency could reduce worldwide temps

#50

Post by 24gttghh »

thehardsphere wrote: post #48
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.

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...
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