8 ms·

"Supported by a solar panel to power a fan and heater, which speed the cycles, the device produces up to 1.3 liters of water per kilogram of MOF per day from de

"Supported by a solar panel to power a fan and heater, which speed the cycles, the device produces up to 1.3 liters of water per kilogram of MOF per day from desert air." This is pretty good, but not yet amazing. It's more energy efficient than a compressor-based dehumidifier, but probably still less efficient than trucking water in from somewhere a few hundred miles away where it's plentiful. Either way, the big question to me is how well it will hold up over hundreds of cycles - there's no report here that I see on whether or not the MOF will also trap dust particles and other things that are likely to decrease efficiency over time.

j_m_b 7y ago
>but probably still less efficient than trucking water in from somewhere a few hundred miles away where it's plentiful I think the convenience and self-sufficiency factor might outweigh the raw efficiency considerations. Petrol and trucks aren't readily available to every villager. With this, there is no more worry about meeting the water truck and doing without. A big concern is what the lifespan of MOFs are. If it can be used for decades with minimal maintenance, it could be a game changer. If not, it would be back to the water truck!
coderintherye 7y ago
You have to keep in mind that trucking in water isn't feasible in a lot of places. Sure, in developed nations there is a good road infrastructure, but it's rarer the further out you go. And it's usually the further out you go that water is more needed. Then, even if you do have a road, have to consider the water truck breaking down, the driver not showing up, etc. Even in developed nations, a water truck doesn't always work, for instance dirt roads with steep inclines and sharp turns.
- magduf 7y ago
  >Then, even if you do have a road, have to consider the water truck breaking down, the driver not showing up, etc. Or militants shooting the driver, hijacking the truck, etc.
AnimalMuppet 7y ago
Less efficient than trucking water? Only if you have a solar powered truck.
- liability 7y ago
  Trucks become solar powered when you put biodiesel in them. But seriously, there comes a point when it's more efficient to build housing for people that is closer to sources of clean water. Whatever they are doing out there in the desert without water and infrastructure probably isn't very productive in the first place, and if they can't even do it sustainably, we should question what the point of it is. Not every environment is suitable for human occupation. How many billions of dollars would you spend shipping bottled water to the moon before you put your foot down and tell people to stop living there?
  - Ultimatt 7y ago
    What if the entire of the USA was a desolate wasteland in 100 years, due to climate change, but Russia was a verdant paradise. Is your expectation everyone goes where its productive still?
    - liability 7y ago
      Either they move, or die. That's presuming nuclear powered desalination on a massive scale never becomes viable. I don't think there are any realistic outcomes to such a scenario that don't involve immense loss of life.
    - imtringued 7y ago
      Yes because even the russians have to move further north.
  - newnewpdro 7y ago
    People living in the desert put in wells like everywhere else that's rural, at least those who can afford it do. In my experience the desert isn't particularly unsuitable for human occupation. Barren wasteland deserts of endless dunes from the movies like the Sahara are not the normal. Certainly not in the USA. What I find is the desert tends to be relatively undesirable land so it's very affordable and abundant. This has the effect of selecting for poor residents who want land of their own but can't afford anything better than desert property, and often can't afford to install a well once they've bought the land. What usually happens is their water gets hauled either by themselves or by a commercial service from the nearest city water supply, it's mostly an inconvenience. Having a system that can directly take atmospheric air and solar energy to produce drinking water on-site for substantially less cost than installing a well would be life-changing for many of these folks. At the very least it would improve their water security since relying on an automobile for your only source of potable water isn't exactly ideal. Presumably one doesn't even need a permit from the county to start extracting water from the air with a device the size of a microwave. This is a huge difference in barrier to entry, especially for the poor. I'm guessing you have no desert experience based on your comment. I live in the Mojave and it's actually quite nice for most of the year. There's such an abundant aquifer near me that Cadiz, Inc. is embroiled in controversy over plans to bottle and sell its water. [0] Here's some food for thought: It's often claimed that mosquitoes have killed more than half the people who have ever lived. Guess what isn't a problem in the desert? Mosquitoes. I recently visited northern MN and frankly find my desert land far more suitable to human occupation than that mosquito infested swamp. [0] https://www.latimes.com/local/lanow/la-me-trump-cadiz-20170404-story.html https://www.latimes.com/local/lanow/la-me-trump-cadiz-201704...
semi-extrinsic 7y ago
> whether or not the MOF will also trap dust particles and other things This is the crux of the matter, yes. Of course you will need filtration to avoid clogging your MOF with sand and dust. Then you increase the power draw, having to push the air through a filter, and you have added a potentially expensive consumable. As TFA states, people have been making MOFs since the mid 90s. And people have been scrambling for applications since. The unanswered questions are, as always: Can they be made cheaply enough? Do they last long enough?
- TheGallopedHigh 7y ago
  As per the article, they can make and Aluminium based MOF for $3 per kilo, so yes.
  - dorusr 7y ago
    I believe it states the price of the aluminum is $3/kg, as opposed to the more expensive zirconium. I don't think they'd know the price of the finished MOF at this stage.
  - cycrutchfield 7y ago
    It says bulk aluminum costs $3 per kilo, not MOF-303.

j_m_b 7y ago

>but probably still less efficient than trucking water in from somewhere a few hundred miles away where it's plentiful I think the convenience and self-sufficiency factor might outweigh the raw efficiency considerations. Petrol and trucks aren't readily available to every villager. With this, there is no more worry about meeting the water truck and doing without. A big concern is what the lifespan of MOFs are. If it can be used for decades with minimal maintenance, it could be a game changer. If not, it would be back to the water truck!

coderintherye 7y ago

You have to keep in mind that trucking in water isn't feasible in a lot of places. Sure, in developed nations there is a good road infrastructure, but it's rarer the further out you go. And it's usually the further out you go that water is more needed. Then, even if you do have a road, have to consider the water truck breaking down, the driver not showing up, etc. Even in developed nations, a water truck doesn't always work, for instance dirt roads with steep inclines and sharp turns.

magduf 7y ago
>Then, even if you do have a road, have to consider the water truck breaking down, the driver not showing up, etc. Or militants shooting the driver, hijacking the truck, etc.

AnimalMuppet 7y ago

Less efficient than trucking water? Only if you have a solar powered truck.

liability 7y ago
Trucks become solar powered when you put biodiesel in them. But seriously, there comes a point when it's more efficient to build housing for people that is closer to sources of clean water. Whatever they are doing out there in the desert without water and infrastructure probably isn't very productive in the first place, and if they can't even do it sustainably, we should question what the point of it is. Not every environment is suitable for human occupation. How many billions of dollars would you spend shipping bottled water to the moon before you put your foot down and tell people to stop living there?
- Ultimatt 7y ago
  What if the entire of the USA was a desolate wasteland in 100 years, due to climate change, but Russia was a verdant paradise. Is your expectation everyone goes where its productive still?
  - liability 7y ago
    Either they move, or die. That's presuming nuclear powered desalination on a massive scale never becomes viable. I don't think there are any realistic outcomes to such a scenario that don't involve immense loss of life.
  - imtringued 7y ago
    Yes because even the russians have to move further north.
- newnewpdro 7y ago
  People living in the desert put in wells like everywhere else that's rural, at least those who can afford it do. In my experience the desert isn't particularly unsuitable for human occupation. Barren wasteland deserts of endless dunes from the movies like the Sahara are not the normal. Certainly not in the USA. What I find is the desert tends to be relatively undesirable land so it's very affordable and abundant. This has the effect of selecting for poor residents who want land of their own but can't afford anything better than desert property, and often can't afford to install a well once they've bought the land. What usually happens is their water gets hauled either by themselves or by a commercial service from the nearest city water supply, it's mostly an inconvenience. Having a system that can directly take atmospheric air and solar energy to produce drinking water on-site for substantially less cost than installing a well would be life-changing for many of these folks. At the very least it would improve their water security since relying on an automobile for your only source of potable water isn't exactly ideal. Presumably one doesn't even need a permit from the county to start extracting water from the air with a device the size of a microwave. This is a huge difference in barrier to entry, especially for the poor. I'm guessing you have no desert experience based on your comment. I live in the Mojave and it's actually quite nice for most of the year. There's such an abundant aquifer near me that Cadiz, Inc. is embroiled in controversy over plans to bottle and sell its water. [0] Here's some food for thought: It's often claimed that mosquitoes have killed more than half the people who have ever lived. Guess what isn't a problem in the desert? Mosquitoes. I recently visited northern MN and frankly find my desert land far more suitable to human occupation than that mosquito infested swamp. [0] https://www.latimes.com/local/lanow/la-me-trump-cadiz-20170404-story.html https://www.latimes.com/local/lanow/la-me-trump-cadiz-201704...

semi-extrinsic 7y ago

> whether or not the MOF will also trap dust particles and other things This is the crux of the matter, yes. Of course you will need filtration to avoid clogging your MOF with sand and dust. Then you increase the power draw, having to push the air through a filter, and you have added a potentially expensive consumable. As TFA states, people have been making MOFs since the mid 90s. And people have been scrambling for applications since. The unanswered questions are, as always: Can they be made cheaply enough? Do they last long enough?

TheGallopedHigh 7y ago
As per the article, they can make and Aluminium based MOF for $3 per kilo, so yes.
- dorusr 7y ago
  I believe it states the price of the aluminum is $3/kg, as opposed to the more expensive zirconium. I don't think they'd know the price of the finished MOF at this stage.
- cycrutchfield 7y ago
  It says bulk aluminum costs $3 per kilo, not MOF-303.