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Improving air conditioner efficiency could reduce worldwide temps

nytimes.com

201–210 of 349 posts

Re: Improving air conditioner efficiency could reduce worldwide temps

#201

Earlier quoted context omitted.

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.

I'm not sure such a thing would work here, but Japan famously ran their "Cool Biz" campaign to encourage people to dress lighter in the summer. https://en.wikipedia.org/wiki/Cool_Biz_campaign

The first company I worked at had cool biz tightly tied to time with zero regard to the actual temperature outside. It usually came too late and ended too early. Thankfully the next place I worked at was a lot more lax in the policy.

Re: Improving air conditioner efficiency could reduce worldwide temps

#202
post #143

Earlier quoted context omitted.

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.

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.

[deleted]

Re: Improving air conditioner efficiency could reduce worldwide temps

#203
post #143

Earlier quoted context omitted.

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.

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.

Yes but I can't say for sure the cause is economic development. It seems likely, but it's a correlation, not a proven cause.

Re: Improving air conditioner efficiency could reduce worldwide temps

#204
post #32

Earlier quoted context omitted.

Isn't there a big fire/explosion risk as these are very flammable?

Most RV's use this combo for the fridge. They don't seem to explode but there does seem to be a number of fires.

RV fridges burn the propane not compress it.

Re: Improving air conditioner efficiency could reduce worldwide temps

#205
post #90
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…

We just replaced our AC system, and while SEER 22 would have saved on electricity, it would have required several thousand dollars more in new duct work. The high efficiency systems require not only variable speed air moving capability, but ducts that work with it as well.

We went from SEER 10 to SEER 15. With the rebalancing that the contractor did, our house is much more comfortable with the thermostat at 80 than it was under the old system at 73.

Re: Improving air conditioner efficiency could reduce worldwide temps

#206
post #171

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…

The current situation is largely caused by artificially low prices of fossil fuels. We are borrowing from the future to fuel our consumption. If we agreed to increase those prices by, say, 5 to 10 times and used the money to fund research towards removing carbon from the atmosphere, the world would become a much better place. Problem is, everybody is afraid of the shock this would cause and everybody thinks only abou…

In Poland, the government recently announced they want to add +0.25 PLN ($0.07, or ~6% of current gasoline prices) of tax for gasoline. The stated reason is increasing the budgets for maintenance of local roads.

Regardless of the issues of stated vs. real reasons, the reaction of people in the country was totally predictable: people are enraged. How dares the government raise the fuel price? You get a similar reaction if you try to suggest an emission tax to any driver.

With this mindset, sadly, we won't get anywhere.

Re: Improving air conditioner efficiency could reduce worldwide temps

#207
post #194

Earlier quoted context omitted.

It's been mentioned elsewhere in this thread, but if you run your refrigerant loop through the ground instead of cooling it using the hot ambient air, you can absolutely achieve that improvement in efficiency. The concept is described here: https://energy.gov/energysaver/geothermal-heat-pumps The amount of efficiency increase you get depends on the ground temp, which varies by latitude, but I've seen 70% reductions i…

> if you run your refrigerant loop through the ground instead of cooling it using the hot ambient air In the same vein, rejecting heat to the cooler night air is a lot more efficient than using hot day air. You can operate a chiller at night and generate a bunch of ice efficiently. During the day, you can melt the ice for cooling at day -- without operating any sort of compressor. Once the melted water gets higher th…

Interesting, are there any writeups you could point me to on how to size a system like this for the average home and what the energy costs are like?

Re: Improving air conditioner efficiency could reduce worldwide temps

#208
post #90

Earlier quoted context omitted.

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…

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 interestin…

Who's the manufacturer?

Re: Improving air conditioner efficiency could reduce worldwide temps

#209
post #90

Earlier quoted context omitted.

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…

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 interestin…

[deleted]

Re: Improving air conditioner efficiency could reduce worldwide temps

#210

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…

CO2, and its interchangeably-used measure of CO2e (which is a sum of all greenhouse gases weighted based on how much they contribute to global warming) is the only pollutant that matters in this context.

Our disposable-good society is a small fraction of our overall impact on the climate. It is 100% possible to power our world with solar, wind, and batteries while keeping the rest of our lives largely unchanged. The only climate-hostile things we can't easily solve for right now are a) beef and b) air travel. Every single HN reader can go all-electric today, and most can sign up for a renewable-energy program through their utility.

If you think our society should build fewer, higher-quality goods then I agree. But doing that won't come close to stopping climate change.

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