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Yes, a building in San Francisco doesn’t need air conditioning in the summer, what a surprise. Make the same design work in Phoenix Arizona and we’ll have somet

Yes, a building in San Francisco doesn’t need air conditioning in the summer, what a surprise. Make the same design work in Phoenix Arizona and we’ll have something.

ceejayoz 7y ago
This is a weird critique. Even in Phoenix, the need for air conditioning can be reduced by designing houses well. As the article notes: > Even in exposed, hot and arid climates, cooler temperatures are never too far away. In Jaipur, the capital of Rajasthan state in northern India, daytime temperatures regularly reach upwards of 40C in the summer months. But just a few metres below ground, the temperature of the earth in the region remains a much gentler 25C, even through the fiercest summer heat.
- adrianN 7y ago
  Building office buildings in a way that makes them essentially giant greenhouses doesn't help with the AC bill either.
  - ghaff 7y ago
    As you get into multi-story office and apartment buildings, your options for passive cooling get pretty significantly constrained. Thick walls, passive roof cooling, maybe partly sunken... These things can work for a standalone house or certain types of commercial buildings but they're harder to work into bigger structures although evaporative cooling at least can be used.
    - ceejayoz 7y ago
      There's a neat example of what can be done with multi-story buildings in Zimbabwe. https://en.wikipedia.org/wiki/Eastgate_Centre,_Harare https://en.wikipedia.org/wiki/Eastgate_Centre,_Harare
      - ghaff 7y ago
        Neat design though, as the article says, Harare has a pretty temperate climate. In general, the higher elevations in a lot of East and Southern Africa have climates that are often as nice as the lower elevations are often not nice.
- masklinn 7y ago
  See also: windcatchers and underground aqueduct (qanats) in traditional egyptian and persian architecture. > But just a few metres below ground, the temperature of the earth in the region remains a much gentler 25C, even through the fiercest summer heat. That can be a risky bit depending how it's used specifically e.g. london's underground was pretty much freezing when it first opened but the clays have a hard time shedding heat so these days the walls warm up the undeground.
  - philjohn 7y ago
    yes - but that's because there are big huge electric motors in there that spew out quite a bit of heat, as well as all the bodies, and the deeper (hotter) tunnels are very closed off. This is talking about digging down a few metres and having a loosely covered courtyard in the space, very different.
- sokoloff 7y ago
  If you pump heat from the building into the ground, isn't that just a form of air conditioning? (Sure, it's a more efficient version than air-source phase-change refrigeration, but it's not without air-conditioning as I see it.)
  - technothrasher 7y ago
    The article is mostly taking about passive solutions. But yeah, geothermal heat pumps are just refrigerant based A/C systems with the condensor (or evaporator, or fancy reversible valve to switch back and forth for heat or cool) stuck in the ground.
- yetihehe 7y ago
  At first, New York and London [0] metro lines were cool too. Pumping heat underground will not solve your problems in the long run. But this is only nitpick to this one particular cooling method. Maybe something like sending your heat to space[1] or better insulation will help. [0] https://www.wired.co.uk/article/central-line-temperature-london-weather-heatwave https://www.wired.co.uk/article/central-line-temperature-lon... > When much of central London’s Tube network opened in the early 1900s, temperatures in tunnels and at stations were recorded at around 14C. [1] https://physicsworld.com/a/keeping-buildings-cool-by-sending-heat-into-outer-space/ https://physicsworld.com/a/keeping-buildings-cool-by-sending...
  - ceejayoz 7y ago
    From the article on London: > To understand how more of the Central line could be cooled down, just look at the Victoria line. In 2006, a similarly experimental groundwater cooling system was installed at Victoria station to lower temperatures in mid-platform areas. In 2011, TfL completed the installation of 13 ventilation shafts throughout the Victoria line, while the new fleet of trains running on the line allows TfL to operate a regenerative braking system, which returns power to the rails when a train brakes. And when a whopping 38 per cent of heat generation on the London Underground comes from trains braking, that’s a pretty big deal. It's basically another example where sensible design can make a huge difference.
- marcinzm 7y ago
  I'm skeptical. Jaipur, right now during the day, has 60% humidity at 90F. If you lower your temperature with transfer into the ground then you're not lowering humidity but only temperature. That means relative humidity will go UP. I suspect even 80F at 90+% humidity will feel really unpleasant.
  - ceejayoz 7y ago
    > I suspect even 80F at 90+% humidity will feel really unpleasant. That's hardly likely in Phoenix.
    - marcinzm 7y ago
      Your quote is about Jaipur and not Phoenix. I am responding to your quote.
      - ceejayoz 7y ago
        The article specifically indicates it (and other techniques in concert) works in Jaipur. It's not going to work 100% of the time in all places, but even in hot, humid areas improvements can be made. > This allows air conditioning to be used very modestly, when it is necessary at all. I'm not sure why every thread about energy efficiency improvements has people come in and do the "it's not a perfect solution for these edge cases" thing. Everyone knows that already, and it's totally beside the point.
  - dsr_ 7y ago
    Boston here: yup, 90% RH at 80F is awful. 40% RH at 80F is merely warm, and a fan works well to alleviate that.
marcinzm 7y ago
Phoenix isn't that bad since it's got cool nights and low humidity which you can work with. Florida on the other hand, good luck.
- chrishynes 7y ago
  Eh, don't think you've been in Phoenix in the summer. Nights are still triple digits, which is the main thing that makes the summer so brutal.
- rwbcxrz 7y ago
  Phoenix regularly has overnight lows above 90F. It's pretty bad.
  - ebiester 7y ago
    The problem is all of the concrete. Get outside the heat dome and it cools considerably. You just have to rethink the building pattern. (White roofs with water collection would be a good start.)
    - rwbcxrz 7y ago
      Agreed. I lived in the southeast valley for 16 years. At the start of it, we were fairly near the edge of the sprawl, and now you have to drive another 20+ miles to get out of suburbia. It's definitely had an effect on temperature, particularly overnight.

Yes, a building in San Francisco doesn’t need air conditioning in the summer, what a surprise. Make the same design work in Phoenix Arizona and we’ll have something.

ceejayoz 7y ago

This is a weird critique. Even in Phoenix, the need for air conditioning can be reduced by designing houses well. As the article notes: > Even in exposed, hot and arid climates, cooler temperatures are never too far away. In Jaipur, the capital of Rajasthan state in northern India, daytime temperatures regularly reach upwards of 40C in the summer months. But just a few metres below ground, the temperature of the earth in the region remains a much gentler 25C, even through the fiercest summer heat.

adrianN 7y ago
Building office buildings in a way that makes them essentially giant greenhouses doesn't help with the AC bill either.
- ghaff 7y ago
  As you get into multi-story office and apartment buildings, your options for passive cooling get pretty significantly constrained. Thick walls, passive roof cooling, maybe partly sunken... These things can work for a standalone house or certain types of commercial buildings but they're harder to work into bigger structures although evaporative cooling at least can be used.
  - ceejayoz 7y ago
    There's a neat example of what can be done with multi-story buildings in Zimbabwe. https://en.wikipedia.org/wiki/Eastgate_Centre,_Harare https://en.wikipedia.org/wiki/Eastgate_Centre,_Harare
    - ghaff 7y ago
      Neat design though, as the article says, Harare has a pretty temperate climate. In general, the higher elevations in a lot of East and Southern Africa have climates that are often as nice as the lower elevations are often not nice.
masklinn 7y ago
See also: windcatchers and underground aqueduct (qanats) in traditional egyptian and persian architecture. > But just a few metres below ground, the temperature of the earth in the region remains a much gentler 25C, even through the fiercest summer heat. That can be a risky bit depending how it's used specifically e.g. london's underground was pretty much freezing when it first opened but the clays have a hard time shedding heat so these days the walls warm up the undeground.
- philjohn 7y ago
  yes - but that's because there are big huge electric motors in there that spew out quite a bit of heat, as well as all the bodies, and the deeper (hotter) tunnels are very closed off. This is talking about digging down a few metres and having a loosely covered courtyard in the space, very different.
sokoloff 7y ago
If you pump heat from the building into the ground, isn't that just a form of air conditioning? (Sure, it's a more efficient version than air-source phase-change refrigeration, but it's not without air-conditioning as I see it.)
- technothrasher 7y ago
  The article is mostly taking about passive solutions. But yeah, geothermal heat pumps are just refrigerant based A/C systems with the condensor (or evaporator, or fancy reversible valve to switch back and forth for heat or cool) stuck in the ground.
yetihehe 7y ago
At first, New York and London [0] metro lines were cool too. Pumping heat underground will not solve your problems in the long run. But this is only nitpick to this one particular cooling method. Maybe something like sending your heat to space[1] or better insulation will help. [0] https://www.wired.co.uk/article/central-line-temperature-london-weather-heatwave https://www.wired.co.uk/article/central-line-temperature-lon... > When much of central London’s Tube network opened in the early 1900s, temperatures in tunnels and at stations were recorded at around 14C. [1] https://physicsworld.com/a/keeping-buildings-cool-by-sending-heat-into-outer-space/ https://physicsworld.com/a/keeping-buildings-cool-by-sending...
- ceejayoz 7y ago
  From the article on London: > To understand how more of the Central line could be cooled down, just look at the Victoria line. In 2006, a similarly experimental groundwater cooling system was installed at Victoria station to lower temperatures in mid-platform areas. In 2011, TfL completed the installation of 13 ventilation shafts throughout the Victoria line, while the new fleet of trains running on the line allows TfL to operate a regenerative braking system, which returns power to the rails when a train brakes. And when a whopping 38 per cent of heat generation on the London Underground comes from trains braking, that’s a pretty big deal. It's basically another example where sensible design can make a huge difference.
marcinzm 7y ago
I'm skeptical. Jaipur, right now during the day, has 60% humidity at 90F. If you lower your temperature with transfer into the ground then you're not lowering humidity but only temperature. That means relative humidity will go UP. I suspect even 80F at 90+% humidity will feel really unpleasant.
- ceejayoz 7y ago
  > I suspect even 80F at 90+% humidity will feel really unpleasant. That's hardly likely in Phoenix.
  - marcinzm 7y ago
    Your quote is about Jaipur and not Phoenix. I am responding to your quote.
    - ceejayoz 7y ago
      The article specifically indicates it (and other techniques in concert) works in Jaipur. It's not going to work 100% of the time in all places, but even in hot, humid areas improvements can be made. > This allows air conditioning to be used very modestly, when it is necessary at all. I'm not sure why every thread about energy efficiency improvements has people come in and do the "it's not a perfect solution for these edge cases" thing. Everyone knows that already, and it's totally beside the point.
- dsr_ 7y ago
  Boston here: yup, 90% RH at 80F is awful. 40% RH at 80F is merely warm, and a fan works well to alleviate that.

marcinzm 7y ago

Phoenix isn't that bad since it's got cool nights and low humidity which you can work with. Florida on the other hand, good luck.

chrishynes 7y ago
Eh, don't think you've been in Phoenix in the summer. Nights are still triple digits, which is the main thing that makes the summer so brutal.
rwbcxrz 7y ago
Phoenix regularly has overnight lows above 90F. It's pretty bad.
- ebiester 7y ago
  The problem is all of the concrete. Get outside the heat dome and it cools considerably. You just have to rethink the building pattern. (White roofs with water collection would be a good start.)
  - rwbcxrz 7y ago
    Agreed. I lived in the southeast valley for 16 years. At the start of it, we were fairly near the edge of the sprawl, and now you have to drive another 20+ miles to get out of suburbia. It's definitely had an effect on temperature, particularly overnight.