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Comment by dheera | Hacker News Reader

I've lived for 10+ years without an air conditioner. I usually just go to common air-conditioned spaces (coffee houses, school campuses) or near the sea where it's cooler.

I hate being at home during the day anyway, but it's also to try to save a little energy ;) Everyone turning ther A/C on is actually making the planet hotter.

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> Everyone turning ther A/C on is actually making the planet hotter.

This really needs to be emphasised to all the newcomers to SF.

In Fremont/San Jose/Sunnyvale you probably will need AC, but most areas you're probably fine with a few fans running, which are more environmentally friendly.

But alas, the culture here is changing. The sales people in our office have this lazy habit of opening the windows and keeping the AC running.

But do you need any heating in SF’s winters?

If so, AC unit might be the most economical option.

Well said, as soon as the mercury rises my family cranks up the A/C, only to exacerbate the issue as all their power comes from Fossil fuels

Even if the energy to run an air conditioner came from a source like hydroelectric power and the machine operated at 100% efficiency, it would still heat the outside air.

A typical air conditioner is one example of a heat pump, a device that moves heat from one location to another. In this case you're pumping heat from inside your house to outside, warming the air around the house.

Your refrigerator is also a heat pump, moving heat from inside the fridge to the outside. This is one reason cats like to climb up on top of the refrigerator (besides the fact that they like to climb on everything) - it's warm up there.

https://en.wikipedia.org/wiki/Heat_pump

It would heat the outside air only temporarily. Eventually the heat would seep back into your house and it would be back like it started.

Of course 100% efficiency isn't actually possible.

It's less about heating the outside air directly and more about carbon emissions from massive cities all using air conditioners at once.

Not saying give up air conditioning altogether, but consider hanging out in an air conditioned public space instead of switching on your own. Libraries, malls, coffee shops, universities, just to name a few.

From the basic energy conservation considerations, it is clear how much heat is produced by the AC - the same amount that it consumes from the power grid. There is no other place that energy can go to, and there's no additional energy that can be converted to heat. So if your AC consumed 1kWh, that's 1kWh of heat that was dissipated. It doesn't matter what's inside the AC, conservation of energy works the same way. BTW the same would be true for any device that consumes 1kWh, unless it creates mass (very uncommon for household devices).

> Everyone turning ther A/C on is actually making the planet hotter.

That's bull. I won't have absolutely any effect on the planet if I run my AC 24/7 for all my life. The scales are way too different. You are free to do what you want but please spare me the sanctimonious baloney.

BTW, how do you get to the sea - I bet it's in a car and not on the back of a unicorn? At least most people do. Same as they get to air-conditioned malls (whose AC would probably be consuming energy couple of orders of magnitude more than that home AC) and other places. As I said, it's your choice how to deal with it but please, less posturing.

Ac works by pumping heat out of the house and pulling Air in that passes by coils with compressed solvent. When solvent changes from liquid to gas when released into the coils under less pressure, the molecules absorb heat energy from the incoming air (gasses inheritely have more energy because the molecules are moving around faster). The gasses used are greenhouse gasses which contribute to making the world hotter. You say it's on a small scale, and I agree with you, but so is an individual cow, but cattle contribute a large percentage of the greenhouse gasses. The collective use of air conditioning does indeed contribute to climate change. While it does push out hot air, I don't think this would have a noticeable immediate effect on the local temperature.

Oh and btw I love AC and am totally wtfing about not having AC now that it's hot and all the fans being sold out wrf.

Thank you, I know how AC works. The point is the difference is minuscule, on home scale. Unless all home AC users start to vent their refrigerant tanks into the atmosphere (which would defeat the whole purpose of having AC), and keep doing it for decades, the effect of it would be nil. In practice, the leaks are small and are promptly fixed because when refrigerant is leaking, AC is useless and nobody wants that. Of course, it would be nice to use even better chemicals (such as HFOs), but even now the contribution of home AC - if properly used and disposed - is small.

> The collective use of air conditioning does indeed contribute to climate change.

Not significantly more than any other use of the same energy.

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