4 ms·

What makes you think that project is relying on passive solar? In green building that concept has been largely superseded by newer standards like Passive House

What makes you think that project is relying on passive solar? In green building that concept has been largely superseded by newer standards like Passive House and Net Zero which generally rely more on air sealing and super-insulation with highly insulated windows.

Xeoncross 4y ago
There is going to be a lot of health fallout though as people start having oxygen depletion from tightly-sealed houses. It's important that even well sealed homes have both A/C fresh air sources as well as ERV/HRV systems that can recapture the heat/cold the house has while replacing the CO2 with outside air.
- Karrot_Kream 4y ago
  ERVs and HRVs are generally part of these designs. Also, nothing stops people from cracking open their windows. The windows are meant to insulate well when closed.
- schiffern 4y ago
  >oxygen depletion I wish people would stop conflating low oxygen with high CO2. Even at 5000 ppm CO2 (which "significantly impair" attention, executive function, and risky decision-making[0]), the oxygen has only dropped from 20.95% to 20.45%. This ~2.5% difference is negligible, equivalent to natural variations in atmospheric pressure. The buildup of CO2 is the issue, not the depletion of O2. [0] https://www.mdpi.com/2073-4433/13/6/891 https://www.mdpi.com/2073-4433/13/6/891
- js8 4y ago
  Maybe put in some plants?
  - deleted 4y ago
    [deleted]
  - chongli 4y ago
    You'd have to put so many plants in your house that the interior would look like one of those rainforest exhibits at the natural history museum. A couple of houseplants on the windowsill won't even move the needle on CO2 levels in a house occupied by a family.
    - nunodonato 4y ago
      source?
      - vkou 4y ago
        Don't need a source, it's simple math. For a plant to absorb 1KG of CO2, it needs to increase in weight by at least ~1Kg. An average human exhales ~1KG of CO2 a day. Unless your house plants are gaining half a ton of mass a year, they aren't meaningfully offsetting your CO2 exhilation.
        tonyarkles 4y ago
        I’m still with you and your point remains, but the plants do release O2 and just retain the C if I recall. Your plants only need to weigh 27% of that at the end of the year, or about 100kg :D
        vkou 4y ago
        Unless your plants are made out of pure diamond, they also need to gain hydrogen, oxygen, and nitrogen in weight. But you are part-right, carbon is ~35-50% of a normal plant's weight.
      - SideburnsOfDoom 4y ago
        Why ask something that's trivial to google yourself? There are numerous good ones, it's a well-known and noncontroversial topic.
  - malfist 4y ago
    Plants absorb near the same amount of O2 at night as they produce during the day. Maybe an algae farm is that you'd need.
- briandon 4y ago
  In addition to concerns relating to carbon dioxide levels, when I contemplate the push for ever-more-tightly-sealed homes and particularly smaller homes with lower ratios of internal air volume to internal surface area (of walls, built-ins like cabinetry, and furniture), the issues stemming from outgassing of volatile organics from the adhesives and sealants as well as from the materials (solid wood became plywood with wood veneering, became sawdust-and-binder with plastic faux-wood veneer, etc.) now composites made of multiple substances and multiple binders and glues. Some years back, "sick building syndrome" was a prominent topic of discussion and there was a push for fresh air, windows that opened, etc. but this seems to have largely dropped off the radar, afaict.
DoreenMichele 4y ago
You are correct that they are viewed as different systems and tend to rely on different strategies: https://ecokit.us/passive-solar-design-vs-passive-house/#:~:text=It%20is%20probably%20because%20of%20their%20similar%20names,been%20taking%20off%20in%20the%20last%20few%20years https://ecokit.us/passive-solar-design-vs-passive-house/#:~:.... To me, it's almost a matter of semantics. In passive solar building design, windows, walls, and floors are made to collect, store, reflect, and distribute solar energy, in the form of heat in the winter and reject solar heat in the summer. This is called passive solar design because, unlike active solar heating systems, it does not involve the use of mechanical and electrical devices.[1] The key to designing a passive solar building is to best take advantage of the local climate performing an accurate site analysis. https://en.m.wikipedia.org/wiki/Passive_solar_building_design https://en.m.wikipedia.org/wiki/Passive_solar_building_desig... I think of passive solar as the umbrella term for such strategies. My understanding is passive house comes from a German project. It shouldn't surprise anyone that strategies which work well in Germany differ from strategies that work in warmer climates. There are also traditional building approaches in Middle Eastern deserts that keep the entire city at bearable temperatures. They historically built on a plateau, oriented streets to be cooled by prevailing winds etc. Both in Mexico and Iran, they have passive air exchange systems that help cool homes. Stairwells in Victorian American homes have similar features and likely served a similar purpose and were probably not merely ostentatious. If you know a better umbrella term for this approach, I'm open to suggestions.
- boulos 4y ago
  > My understanding is passive house comes from a German project. It shouldn't surprise anyone that strategies which work well in Germany differ from strategies that work in warmer climates. It actually started in North America around the time of the oil embargo as a mechanism to reduce energy costs. (See the history section of https://en.m.wikipedia.org/wiki/Passive_house https://en.m.wikipedia.org/wiki/Passive_house). Once that shock passed, people went back to not caring. Even at the time, and still today, most write ups are focused on harsh climates like New England or Canada in Winter, because it's harder. It's also the case that in milder climates, the cost to make your home passive has historically been higher than just paying the subsidized bills (and/or requires capital). So most of the US hasn't cared (again) until recently.

Xeoncross 4y ago

There is going to be a lot of health fallout though as people start having oxygen depletion from tightly-sealed houses. It's important that even well sealed homes have both A/C fresh air sources as well as ERV/HRV systems that can recapture the heat/cold the house has while replacing the CO2 with outside air.

Karrot_Kream 4y ago
ERVs and HRVs are generally part of these designs. Also, nothing stops people from cracking open their windows. The windows are meant to insulate well when closed.
schiffern 4y ago
>oxygen depletion I wish people would stop conflating low oxygen with high CO2. Even at 5000 ppm CO2 (which "significantly impair" attention, executive function, and risky decision-making[0]), the oxygen has only dropped from 20.95% to 20.45%. This ~2.5% difference is negligible, equivalent to natural variations in atmospheric pressure. The buildup of CO2 is the issue, not the depletion of O2. [0] https://www.mdpi.com/2073-4433/13/6/891 https://www.mdpi.com/2073-4433/13/6/891
js8 4y ago
Maybe put in some plants?
- deleted 4y ago
  [deleted]
- chongli 4y ago
  You'd have to put so many plants in your house that the interior would look like one of those rainforest exhibits at the natural history museum. A couple of houseplants on the windowsill won't even move the needle on CO2 levels in a house occupied by a family.
  - nunodonato 4y ago
    source?
    - vkou 4y ago
      Don't need a source, it's simple math. For a plant to absorb 1KG of CO2, it needs to increase in weight by at least ~1Kg. An average human exhales ~1KG of CO2 a day. Unless your house plants are gaining half a ton of mass a year, they aren't meaningfully offsetting your CO2 exhilation.
      - tonyarkles 4y ago
        I’m still with you and your point remains, but the plants do release O2 and just retain the C if I recall. Your plants only need to weigh 27% of that at the end of the year, or about 100kg :D
        vkou 4y ago
        Unless your plants are made out of pure diamond, they also need to gain hydrogen, oxygen, and nitrogen in weight. But you are part-right, carbon is ~35-50% of a normal plant's weight.
    - SideburnsOfDoom 4y ago
      Why ask something that's trivial to google yourself? There are numerous good ones, it's a well-known and noncontroversial topic.
- malfist 4y ago
  Plants absorb near the same amount of O2 at night as they produce during the day. Maybe an algae farm is that you'd need.
briandon 4y ago
In addition to concerns relating to carbon dioxide levels, when I contemplate the push for ever-more-tightly-sealed homes and particularly smaller homes with lower ratios of internal air volume to internal surface area (of walls, built-ins like cabinetry, and furniture), the issues stemming from outgassing of volatile organics from the adhesives and sealants as well as from the materials (solid wood became plywood with wood veneering, became sawdust-and-binder with plastic faux-wood veneer, etc.) now composites made of multiple substances and multiple binders and glues. Some years back, "sick building syndrome" was a prominent topic of discussion and there was a push for fresh air, windows that opened, etc. but this seems to have largely dropped off the radar, afaict.

DoreenMichele 4y ago

You are correct that they are viewed as different systems and tend to rely on different strategies: https://ecokit.us/passive-solar-design-vs-passive-house/#:~:text=It%20is%20probably%20because%20of%20their%20similar%20names,been%20taking%20off%20in%20the%20last%20few%20years https://ecokit.us/passive-solar-design-vs-passive-house/#:~:.... To me, it's almost a matter of semantics. In passive solar building design, windows, walls, and floors are made to collect, store, reflect, and distribute solar energy, in the form of heat in the winter and reject solar heat in the summer. This is called passive solar design because, unlike active solar heating systems, it does not involve the use of mechanical and electrical devices.[1] The key to designing a passive solar building is to best take advantage of the local climate performing an accurate site analysis. https://en.m.wikipedia.org/wiki/Passive_solar_building_design https://en.m.wikipedia.org/wiki/Passive_solar_building_desig... I think of passive solar as the umbrella term for such strategies. My understanding is passive house comes from a German project. It shouldn't surprise anyone that strategies which work well in Germany differ from strategies that work in warmer climates. There are also traditional building approaches in Middle Eastern deserts that keep the entire city at bearable temperatures. They historically built on a plateau, oriented streets to be cooled by prevailing winds etc. Both in Mexico and Iran, they have passive air exchange systems that help cool homes. Stairwells in Victorian American homes have similar features and likely served a similar purpose and were probably not merely ostentatious. If you know a better umbrella term for this approach, I'm open to suggestions.

boulos 4y ago
> My understanding is passive house comes from a German project. It shouldn't surprise anyone that strategies which work well in Germany differ from strategies that work in warmer climates. It actually started in North America around the time of the oil embargo as a mechanism to reduce energy costs. (See the history section of https://en.m.wikipedia.org/wiki/Passive_house https://en.m.wikipedia.org/wiki/Passive_house). Once that shock passed, people went back to not caring. Even at the time, and still today, most write ups are focused on harsh climates like New England or Canada in Winter, because it's harder. It's also the case that in milder climates, the cost to make your home passive has historically been higher than just paying the subsidized bills (and/or requires capital). So most of the US hasn't cared (again) until recently.