This past summer I tried to forgo AC. It lasted until the dog days of July/August where the humidity was so high that it made me lethargic. I gave up and setup my AC in the window.
Then I traveled to Spain in August and was hosted at someones house for a week. They had no AC. And their method is simple: split the day in two resulting in the siesta. During the day in the intense heat you're tired by 3 PM and nearly dead by 5. The Spaniards? They go home and go to sleep for an hour or two then wake up when the sun has gone down and it cools down. Most things close at 5PM and reopen around 8PM. People stay out late too - I saw parents chatting on benches at a playground after midnight while their children played.
We have ways around this heat problem. Though I know people so spoiled that they INSIST their home and workspace must be at 60F even in 100F heat. They'll burn forests just so they wont be inconvenienced by a bead of sweat.
I don't consider that being uncomfortable is a solution.
There are actual solutions used by hot countries to deal with the heat: ventilation, vegetation, construction techniques, etc... But adjusting work schedules so that you have a hour or two of poor quality sleep when you can't do anything else is the kind of thing you do when you have no other choice, not a solution.
I have nothing against the Spanish schedule, but I would rather not do my siesta in an unbearably hot place. And yes, AC is a solution.
AC doesn't have to be that bad. Set a reasonable temperature, combine it with good insulation, etc... Same idea as for heating in the winter.
A study from 2023 estimated a worst case blackout in Phoenix AZ could approach 1% fatality. Considering power demand would be at its highest during a heat wave, the odds of this worst case scenario are quite high.
"In Phoenix, where the lowest daily high temperature over the 5 day heat wave is 43 °C and daily minimum temperatures average 32 °C, the rate of heat-related mortality increases by about 700% relative to the Power On scenario, reflecting the extremity of heat exposures in a desert city in the absence of mechanical AC. As reported in Figure 3, the estimated rate of heat-related mortality for the Power Off scenario in Phoenix is 917 (approximate total =13,250 deaths), which approaches 1% of the synthetic population."
If you are doing it for the environment, you should forgo heat. 100F to 70F is only a 30 degree delta. If you have a heat pump, this is the same amount of energy heating your home to 70F from 40F. If you have natural gas heating, now we are talking about the same amount of energy when it is low 50's outside.
How many forests will you burn to not just wear two sweaters and blanket?
I think many of us (myself included) operate under this fundamental assumption that air conditioning is somehow sinful and wrong, against the natural order of things, but heating spaces is a good and worthwhile use of resources.
I made a slightly-snarky comment along these lines once, and a fellow commenter on HN pointed out how efficient air conditioning is. For one, it's always accomplished via heat pump; eg, moving heat, so the only byproducts are electricity consumption and waste heat. We know how to produce clean electricity. On the flip side, heating indoor spaces also produces waste heat, but a lot more of it. Much worse, the vast majority of home heating (at least in the US) is done by burning fossil fuels. If you compare the heating demands of the northeast to the cooling demands of the south, in terms of BTUs, the heat demands are way more intensive.
The most important factor in this equation is the temperature change required. The temperature differential between a winter temp of 20 or 30F to an indoor temp of 70F requires SO much more energy than cooling from a summer temp of 90F to indoor temp of 70F.
So I can remain smug about living in a mild climate in the Bay Area; my total energy consumption is much lower than the average home. But I probably shouldn't feel smug about not needing A/C when the real problem is the gas furnace I run every morning and part of the day, for months on end, from November to March.
(My house is actually currently missing several walls; the gas furnace has been thrown in the trash and it's being replaced with 3 heat pumps, which will give me both A/C _and_ more efficient heat. No thanks to PG&E, which will reward my GHG reductions by charging me out the ass for the electricity required to heat my home).
AC use largely corresponds with peak solar, though, so it doesn't seem like a particularly tough problem to solve? In California, there's often a surplus of solar energy on hot days.
Would reduced heating due to warmer winters offset this? Global carbon emissions due to heating are approximately 4 times the amount of carbon emissions due to cooling [0].
(Of course, the ideal scenario is not that rising carbon emissions from increased cooling get offset by lower emissions from decreased heating, but rather that we transition to abundant carbon-free energy from solar, wind, nuclear, etc. and are able to keep our houses as cool as we want in the summer and as warm as we want in the winter without any environmental consequences.)
It seems to me that with sufficient insulation a modern or futuristic home could take advantage of the seasonal energy gradient to smoothe out the domestic interior climate, essentially acting as a battery or reservoir to capture energy in summer and dispense it in winter. I suppose that's basically what photovoltaics do. I'm also somewhat aware and intrigued by non-electric solar energy systems, like convection of thermal oil through pipes?
Heat pumps move heat, the small extra amount from the compressor does not change the game. On the other hand, things change significantly with the huge thermal mass of reinforced concrete buildings exposed to the sun, large glass facades exposed to the sun, and bare earth exposed to the sun.
Heat rises and dissipates from the atmosphere, so the point isn't the heat moved from a closed bit of atmosphere to an open one heading towards space, but rather the massive thermal mass of buildings constructed without ventilated facades, and fields and deserts without photovoltaic panels to stop the heat from massively warming the ground.
However, people don't like saying this; they don't like saying that it's the dense city that increases global warming and isn't ecological at all. They don't like it because the city serves to extract wealth from the many for the few.
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Then I traveled to Spain in August and was hosted at someones house for a week. They had no AC. And their method is simple: split the day in two resulting in the siesta. During the day in the intense heat you're tired by 3 PM and nearly dead by 5. The Spaniards? They go home and go to sleep for an hour or two then wake up when the sun has gone down and it cools down. Most things close at 5PM and reopen around 8PM. People stay out late too - I saw parents chatting on benches at a playground after midnight while their children played.
We have ways around this heat problem. Though I know people so spoiled that they INSIST their home and workspace must be at 60F even in 100F heat. They'll burn forests just so they wont be inconvenienced by a bead of sweat.
https://www.reuters.com/sustainability/climate-energy/heatwa...
> We have ways around this heat problem
I don't consider that being uncomfortable is a solution.
There are actual solutions used by hot countries to deal with the heat: ventilation, vegetation, construction techniques, etc... But adjusting work schedules so that you have a hour or two of poor quality sleep when you can't do anything else is the kind of thing you do when you have no other choice, not a solution.
I have nothing against the Spanish schedule, but I would rather not do my siesta in an unbearably hot place. And yes, AC is a solution.
AC doesn't have to be that bad. Set a reasonable temperature, combine it with good insulation, etc... Same idea as for heating in the winter.
https://pubs.acs.org/doi/10.1021/acs.est.2c09588
"In Phoenix, where the lowest daily high temperature over the 5 day heat wave is 43 °C and daily minimum temperatures average 32 °C, the rate of heat-related mortality increases by about 700% relative to the Power On scenario, reflecting the extremity of heat exposures in a desert city in the absence of mechanical AC. As reported in Figure 3, the estimated rate of heat-related mortality for the Power Off scenario in Phoenix is 917 (approximate total =13,250 deaths), which approaches 1% of the synthetic population."
How many forests will you burn to not just wear two sweaters and blanket?
Shops and stuff that require outdoor labor yeah for sure. This doesn't work for workers mandated in the 9-5 jobs like office work.
And personally, I'd rather my workday is finished at 5 PM instead of 8 PM with a long break towards the mid-end of the workday.
I made a slightly-snarky comment along these lines once, and a fellow commenter on HN pointed out how efficient air conditioning is. For one, it's always accomplished via heat pump; eg, moving heat, so the only byproducts are electricity consumption and waste heat. We know how to produce clean electricity. On the flip side, heating indoor spaces also produces waste heat, but a lot more of it. Much worse, the vast majority of home heating (at least in the US) is done by burning fossil fuels. If you compare the heating demands of the northeast to the cooling demands of the south, in terms of BTUs, the heat demands are way more intensive.
The most important factor in this equation is the temperature change required. The temperature differential between a winter temp of 20 or 30F to an indoor temp of 70F requires SO much more energy than cooling from a summer temp of 90F to indoor temp of 70F.
So I can remain smug about living in a mild climate in the Bay Area; my total energy consumption is much lower than the average home. But I probably shouldn't feel smug about not needing A/C when the real problem is the gas furnace I run every morning and part of the day, for months on end, from November to March.
(My house is actually currently missing several walls; the gas furnace has been thrown in the trash and it's being replaced with 3 heat pumps, which will give me both A/C _and_ more efficient heat. No thanks to PG&E, which will reward my GHG reductions by charging me out the ass for the electricity required to heat my home).
(Of course, the ideal scenario is not that rising carbon emissions from increased cooling get offset by lower emissions from decreased heating, but rather that we transition to abundant carbon-free energy from solar, wind, nuclear, etc. and are able to keep our houses as cool as we want in the summer and as warm as we want in the winter without any environmental consequences.)
[0] https://ourworldindata.org/grapher/co2-heating-cooling
Heat rises and dissipates from the atmosphere, so the point isn't the heat moved from a closed bit of atmosphere to an open one heading towards space, but rather the massive thermal mass of buildings constructed without ventilated facades, and fields and deserts without photovoltaic panels to stop the heat from massively warming the ground.
However, people don't like saying this; they don't like saying that it's the dense city that increases global warming and isn't ecological at all. They don't like it because the city serves to extract wealth from the many for the few.