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For anyone trying to understand whether dehumidification alone is enough to make them comfortable try the link below - load the 'givoni' comfort overlay and you

For anyone trying to understand whether dehumidification alone is enough to make them comfortable try the link below - load the 'givoni' comfort overlay and your city's weather chart. If most of the weather is [edit] vertically above the comfort zone or possibly the natural ventilation zone adjacent [/edit i originally wrote in the 'evaporative cooling' zone shown which is wrong] its probably a good choice for you. https://drajmarsh.bitbucket.io/psychro-chart2d.html https://drajmarsh.bitbucket.io/psychro-chart2d.html

jonnycomputer 4y ago
Cool! So, you set the Givoni Bioclimatic Chart overlay on? Grew up in the evaporative zone, and it worked well, except on the hottest of days (which come now more often..). Now I live in a much more humid place, which seems to be in natural ventilation/mass cooling zones (overlap of the boxes is a tad confusing to read.
- Bilal_io 4y ago
  > you set the Givoni Bioclimatic Chart overlay on? I think it depends on you and what you're comfortable with.
  - jonnycomputer 4y ago
    The overlay shows the cooling system zones.
sonofhans 4y ago
It’s a fascinating tool and thanks for the link! But oh my word — I need to find and download a weather station file, then upload it again to the same tool? I don’t spend much time in GIS tools, but this feels almost maliciously opaque :D These instructions are hidden behind a “Toggle Instructions” button which is hidden in a popup which is hidden in a select control: > “Once you have found the right weather station, select its indicator and click the 'Download Weather File' link in the popup. This will download the selected file to local storage so you will need to select the 'Load...' button or the 'Load Weather File...' menu item and locate the downloaded file on your system.” I mean, I UX for a living and I’ve seen some daft shit, but I’ve rarely seen a tool so useful and polished in its presentation which presents a less-clear surface area to the user. I want to put a frame around it somehow, as The Master Antipattern.
- jonnycomputer 4y ago
  I don't like to criticize things I get for free.
  - bicijay 4y ago
    I mean... Why not?
    - Godel_unicode 4y ago
      It’s extremely rude, and a great way to convince people who make useful free stuff that the world is composed of assholes and that it’s not worth it.
      - bawolff 4y ago
        As someone who has made free stuff in the past, what's even the point if other people don't engage with it? And does it even count as engagement if its just fluff and not critical engagement? Positive vibes only makes the positive vibes meaningless.
        Godel_unicode 4y ago
        As someone who has made lots of free stuff that tons of people actually use, the internet is full of people who think that they are super insightful and that their scathing indictments of the shade of grey that you picked are incredibly useful. It’s full of people who think that they are entitled to have no social skills because they “know UX”. It’s orders of magnitude easier to destroy than to create, and our culture is all about supposed experts gate-keeping with their banal comments about UX problems that boil down to personal preference.
        bawolff 4y ago
        To be clear, i definitely agree, the internet is full of crazy people with irrational complaints. I suppose i consider that part of the price of putting oneself out there. Its hard to imagine getting rid of that without throwing the baby out with the bath water, so to speak.
tiahura 4y ago
I don’t think this is intended to be used in isolation. Cooling dry air is much less energy intensive than cooling dry air + a bunch of water. So, this device efficiently removes the moisture from the air, allowing the ac system to do less work.
- criddell 4y ago
  AC systems are pretty good at dehumidifying as well. I'm going to be replacing my home AC system soon (it's 13 years old) and was asking our AC maintenance guy about getting an oversized system. In central Texas days approaching 110 seem to be the norm these days. In this weather, my "correctly" sized system can only drop the temperature around 25 degrees different than the outside. He advised against going oversized because apparently a big system cools faster than it removes moisture and you can end up with a block of ice at the exchanger or get condensation and then mold inside. I was thinking a smarter thermostat should be able to monitor humidity in the air and run the AC at a low level, ramping up as moisture goes down, but that doesn't seem to be a feature in any of them (product idea?). Maybe a separate dehumidifier like the one in the article combined with an oversized system could work?
  - istjohn 4y ago
    If you dehumidify first, you it'll be much easier for your existing system to cool the air.
    - criddell 4y ago
      My AC guy said that a right sized system in Texas will never be able to pull the temperature down more than about 25 degrees Fahrenheit. This is the limit I’m trying to get around and I know it’s possible because systems in hotter places can do (like in Arizona) and commercial systems in shopping malls and stadiums can do it too.
      - UncleEntity 4y ago
        Just guessing here but “right sized” might be relative to historic temperatures and don’t take into account the extremes? In Arizona 117 is common enough that you’d expect the AC to handle it with no problem but Texas it probably isn’t that common (guessing). Think the hottest it got since I’ve lived there was 122. People also commonly don’t cool their houses too low because it gets expensive, my sister used to have a McMansion and their AC bill was a lot (something like $400/month) and they were only cooling to around 78 or so.
leereeves 4y ago
> whether dehumidification alone is enough to make them comfortable ... if most of the weather is in the 'evaporative cooling' zone shown its probably a good choice for you. That doesn't seem right - the evaporative cooling zone includes conditions like 40C 1% humidity. What would dehumidification alone do under those conditions?
- jonnycomputer 4y ago
  Evaporative cooling is where you blow a fan through a wet filter, which cools the air. Works in very arid places; it humidifies the air.
  - leereeves 4y ago
    I know, but I think twelvechairs said "dehumidification alone" (with neither AC nor evap cooling) was a good choice under similar conditions. Dehumidification after evap cooling would make sense.
    - jonnycomputer 4y ago
      Oh, could be. The humidity is a comfort issue all by itself (and with drier air we can cool ourselves with sweat).
    - hgomersall 4y ago
      I don't understand this. I can't understand how the thermodynamics works to not simply heat the air back up again when you dehumidify. I guess you can somehow have all the latent heat of vaporisation go into the water? Can anyone explain this? Surely an adsorber based system must release that energy at some point.
  - hgomersall 4y ago
    It works in less arid places too. You can use the humidified cool air to cool incoming air. The now warm air is pumped out. Essentially, you can achieve this by putting a wet filter on the house outflow of an MVHR system, before the heat exchanger. The problem with MVHR is that the flow rates aren't very high. I have an inkling though that with a well designed, efficient house you could maintain a more consistently comfortable temperature with very low energy usage (think a few W and perhaps 1 l/hr water). The psychrometric chart suggests you can get a temperature delta of better than 10 degrees Celsius at 35 degrees with 40% RH.
Terretta 4y ago
Incredibly cool (ahem) resource, though it seems to prefer temps about 5C higher than those preferred by people who like AC.
- joshspankit 4y ago
  I prefer temps about 3.5C lower. My ideal indoor work temp is 17.5C +-1. At 23, my brain is noticeably groggy. It’s endlessly fascinating how different we can all be.
  - antisthenes 4y ago
    Are you overweight?
    - joshspankit 4y ago
      Nope. I just run hot. I’m built for long dry winters with a lot of ice and snow.
- leetcrew 4y ago
  I'm thinking there is a lot of context here I am missing as a layman. you can shift all the zones (including comfort zone) up and down the chart by adjusting the "mean outdoor temp" slider. people don't really work that way, unless we are assuming that they keep wearing their outdoor clothes inside maybe?

jonnycomputer 4y ago

Cool! So, you set the Givoni Bioclimatic Chart overlay on? Grew up in the evaporative zone, and it worked well, except on the hottest of days (which come now more often..). Now I live in a much more humid place, which seems to be in natural ventilation/mass cooling zones (overlap of the boxes is a tad confusing to read.

Bilal_io 4y ago
> you set the Givoni Bioclimatic Chart overlay on? I think it depends on you and what you're comfortable with.
- jonnycomputer 4y ago
  The overlay shows the cooling system zones.

sonofhans 4y ago

It’s a fascinating tool and thanks for the link! But oh my word — I need to find and download a weather station file, then upload it again to the same tool? I don’t spend much time in GIS tools, but this feels almost maliciously opaque :D These instructions are hidden behind a “Toggle Instructions” button which is hidden in a popup which is hidden in a select control: > “Once you have found the right weather station, select its indicator and click the 'Download Weather File' link in the popup. This will download the selected file to local storage so you will need to select the 'Load...' button or the 'Load Weather File...' menu item and locate the downloaded file on your system.” I mean, I UX for a living and I’ve seen some daft shit, but I’ve rarely seen a tool so useful and polished in its presentation which presents a less-clear surface area to the user. I want to put a frame around it somehow, as The Master Antipattern.

jonnycomputer 4y ago
I don't like to criticize things I get for free.
- bicijay 4y ago
  I mean... Why not?
  - Godel_unicode 4y ago
    It’s extremely rude, and a great way to convince people who make useful free stuff that the world is composed of assholes and that it’s not worth it.
    - bawolff 4y ago
      As someone who has made free stuff in the past, what's even the point if other people don't engage with it? And does it even count as engagement if its just fluff and not critical engagement? Positive vibes only makes the positive vibes meaningless.
      - Godel_unicode 4y ago
        As someone who has made lots of free stuff that tons of people actually use, the internet is full of people who think that they are super insightful and that their scathing indictments of the shade of grey that you picked are incredibly useful. It’s full of people who think that they are entitled to have no social skills because they “know UX”. It’s orders of magnitude easier to destroy than to create, and our culture is all about supposed experts gate-keeping with their banal comments about UX problems that boil down to personal preference.
        bawolff 4y ago
        To be clear, i definitely agree, the internet is full of crazy people with irrational complaints. I suppose i consider that part of the price of putting oneself out there. Its hard to imagine getting rid of that without throwing the baby out with the bath water, so to speak.

tiahura 4y ago

I don’t think this is intended to be used in isolation. Cooling dry air is much less energy intensive than cooling dry air + a bunch of water. So, this device efficiently removes the moisture from the air, allowing the ac system to do less work.

criddell 4y ago
AC systems are pretty good at dehumidifying as well. I'm going to be replacing my home AC system soon (it's 13 years old) and was asking our AC maintenance guy about getting an oversized system. In central Texas days approaching 110 seem to be the norm these days. In this weather, my "correctly" sized system can only drop the temperature around 25 degrees different than the outside. He advised against going oversized because apparently a big system cools faster than it removes moisture and you can end up with a block of ice at the exchanger or get condensation and then mold inside. I was thinking a smarter thermostat should be able to monitor humidity in the air and run the AC at a low level, ramping up as moisture goes down, but that doesn't seem to be a feature in any of them (product idea?). Maybe a separate dehumidifier like the one in the article combined with an oversized system could work?
- istjohn 4y ago
  If you dehumidify first, you it'll be much easier for your existing system to cool the air.
  - criddell 4y ago
    My AC guy said that a right sized system in Texas will never be able to pull the temperature down more than about 25 degrees Fahrenheit. This is the limit I’m trying to get around and I know it’s possible because systems in hotter places can do (like in Arizona) and commercial systems in shopping malls and stadiums can do it too.
    - UncleEntity 4y ago
      Just guessing here but “right sized” might be relative to historic temperatures and don’t take into account the extremes? In Arizona 117 is common enough that you’d expect the AC to handle it with no problem but Texas it probably isn’t that common (guessing). Think the hottest it got since I’ve lived there was 122. People also commonly don’t cool their houses too low because it gets expensive, my sister used to have a McMansion and their AC bill was a lot (something like $400/month) and they were only cooling to around 78 or so.

leereeves 4y ago

> whether dehumidification alone is enough to make them comfortable ... if most of the weather is in the 'evaporative cooling' zone shown its probably a good choice for you. That doesn't seem right - the evaporative cooling zone includes conditions like 40C 1% humidity. What would dehumidification alone do under those conditions?

jonnycomputer 4y ago
Evaporative cooling is where you blow a fan through a wet filter, which cools the air. Works in very arid places; it humidifies the air.
- leereeves 4y ago
  I know, but I think twelvechairs said "dehumidification alone" (with neither AC nor evap cooling) was a good choice under similar conditions. Dehumidification after evap cooling would make sense.
  - jonnycomputer 4y ago
    Oh, could be. The humidity is a comfort issue all by itself (and with drier air we can cool ourselves with sweat).
  - hgomersall 4y ago
    I don't understand this. I can't understand how the thermodynamics works to not simply heat the air back up again when you dehumidify. I guess you can somehow have all the latent heat of vaporisation go into the water? Can anyone explain this? Surely an adsorber based system must release that energy at some point.
- hgomersall 4y ago
  It works in less arid places too. You can use the humidified cool air to cool incoming air. The now warm air is pumped out. Essentially, you can achieve this by putting a wet filter on the house outflow of an MVHR system, before the heat exchanger. The problem with MVHR is that the flow rates aren't very high. I have an inkling though that with a well designed, efficient house you could maintain a more consistently comfortable temperature with very low energy usage (think a few W and perhaps 1 l/hr water). The psychrometric chart suggests you can get a temperature delta of better than 10 degrees Celsius at 35 degrees with 40% RH.

Terretta 4y ago

Incredibly cool (ahem) resource, though it seems to prefer temps about 5C higher than those preferred by people who like AC.

joshspankit 4y ago
I prefer temps about 3.5C lower. My ideal indoor work temp is 17.5C +-1. At 23, my brain is noticeably groggy. It’s endlessly fascinating how different we can all be.
- antisthenes 4y ago
  Are you overweight?
  - joshspankit 4y ago
    Nope. I just run hot. I’m built for long dry winters with a lot of ice and snow.
leetcrew 4y ago
I'm thinking there is a lot of context here I am missing as a layman. you can shift all the zones (including comfort zone) up and down the chart by adjusting the "mean outdoor temp" slider. people don't really work that way, unless we are assuming that they keep wearing their outdoor clothes inside maybe?