5 ms·

Pump seawater to Nevada and cover it in desalination greenhouses. http://www.seawatergreenhouse.com/ http://www.seawatergreenhouse.com/

schiffern 13y ago
How is this better than local rainwater collection? Rainwater is desalination, you just cheated and let nature do the expensive part. Heck, lots of rainwater is already collected in gutters/roof drains, but is contaminated when it falls on the ground instead of into a tank. For irrigation all that is necessary is to soak the rainwater in as soon as possible to prevent evaporation and runoff, since potability is not a requirement. This is even cheaper than rooftop catchment. Of course you may need to re-green the upwind deserts first (since ~80% of terrestrial rainfall comes from plants, not evaporation), but we already have that technology. http://www.youtube.com/watch?v=K1rKDXuZ8C0 http://www.youtube.com/watch?v=K1rKDXuZ8C0 This is hardly unprecedented. The CCC installed thousands of miles of swales during the Depression (that function to this day), but nowadays most people don't even know what a swale is.
- moocowduckquack 13y ago
  How is this better than local rainwater collection? It works when there is no rain without needing a tank big enough to last a several year long drought. The architecture of the greenhouse acts as a solar desalinator that in testing creates more water than is needed to irrigate the plants, so it not only grows plants, but also can provide clean water in the desert.
  - Zancarius 13y ago
    I find it curious that on HN of all places, there are some who seem appalled that technology could be used to offset much of what we've done, largely as a fault of technological advancement. That's not to say I'm against conservation. I think conservation is a necessity that few appreciate (having lived in a desert all my life, I have a certain appreciation for scarce resources), but comments like the one you replied to are exactly the kind we don't need. That is, dismissal of alternate solutions isn't going to help the problem get any better. Out here, there's a large, untapped reservoir of brine that would be ample water to supply the neighboring communities for decades or more. The local government continues to humor bonds to build a desalinization plant every 10 years with conditions that the money will be redirected after 3 years if the plant isn't built, and unsurprisingly, the plant is never built. These greenhouses, if they work, would be a worthwhile experiment and probably substantially cheaper considering the wider variety of crops that could be grown and sold. Not to mention local growers could continue growing their crops without ruining the freshwater wells of their neighbors by running them dry. I just doubt it'll happen until the cost of pumping fresh water becomes too expensive or the wells are run completely dry.
    - schiffern 13y ago
      >comments like the one you replied to are exactly the kind we don't need. GP here. :) I'm 100% in favor of using technology "to offset much of what we've done, largely as a fault of technological advancement." After all, rainwater collection is technology! But desalination isn't that kind of technology — it's the destructive kind. My question was genuine. What advantage does plastic greenhouse desalination have over rooftop rainwater harvesting? It uses less land. It costs less. It produces less pollution. No piped distribution to tear up the streets for every 50 years. No energy needed to pump water long distances. The only advantage I can see is that under desalination, someone gets to control your access to water. Advantageous for them I mean.
      - Zancarius 13y ago
        > But desalination isn't that kind of technology — it's the destructive kind. But is it really? You're effectively doing what occurs in nature. Clearing land and building a distribution infrastructure is destructive, but certainly no more than what is already going to happen regardless of whether or not desalinization is used. Pumping from salt water aquifers might qualify as well. > My question was genuine. It was, but your comment seemed dismissive of alternatives. I don't think that objectively adds anything to the conversation. I apologize if that wasn't your intent. I can see a solar desalinization system in place in areas where much of the water you encounter underground is brine or otherwise non-potable, and it's particularly useful in areas where other methods of collection won't work. Yes, it has the potential drawback of kicking the can farther down the road in terms of potentially extracting water faster than it's replaced. But that said, in much of the west, the topography lends itself well to draining much of the run off into large basins and water ingress likely far outpaces whatever could be pumped out of the ground. Perhaps a hybrid (rainfall collection + solar desalinization) would be ideal. I think you're focusing exclusively on the advertised "seawater greenhouse" and may not be aware of the benefits such a design would have in areas where there certainly is plentiful salt water, just not from a sea.
        deleted 13y ago
        [deleted]
  - schiffern 13y ago
    > big enough to last a several year long drought You're way overestimating the size needed. Even in drought years there is substantial precipitation, but generally it happens at the wrong time of year. Often you'll have flooding in the same year as drought! See this recent example: http://news.nationalgeographic.com/news/2013/09/130913-colorado-flood-boulder-climate-change-drought-fires/ http://news.nationalgeographic.com/news/2013/09/130913-color... That flooding is made worse by hardware (meaning roofs, concrete, etc) that prevents infiltration and overwhelms surrounding areas. It's often cheaper to oversize your catchment area and direct tank overflow to a nearby garden. Generally the available roof area isn't the limiting factor, but I encourage you to verify this by looking up annual rainfall numbers for areas you're interested in. Do you know how much rain falls on your roof each year?
- crusso 13y ago
  nowadays most people don't even know what a swale is crusso raises his hand then goes off to google.
  - GFischer 13y ago
    Me too, you always learn something new :) http://en.wikipedia.org/wiki/Swale_(landform) http://en.wikipedia.org/wiki/Swale_(landform)
    - angersock 13y ago
      Wow, it's like Houston personified.
- huherto 13y ago
  Amazing, I want to believe. This is such a big problem in my home town in northern Mexico/American southwest.
bjelkeman-again 13y ago
I spent years volunteering with Seawater Greenhouse and Charlie Paton, the inventor, including working in one of the pilot plants in Australia for a short while. They are very interesting technology and if I wasn't working on the organization I am working on now I would probably be working with a large scale Seawater Greenhouse installation somewhere today.
- moocowduckquack 13y ago
  That is really good of you. Massive amounts of respect. Out of interest, what is it you are now working on? edit - I just had a look at what you are doing through your username, akvo looks pretty cool.
  - bjelkeman-again 13y ago
    Thanks! We try.

schiffern 13y ago

How is this better than local rainwater collection? Rainwater is desalination, you just cheated and let nature do the expensive part. Heck, lots of rainwater is already collected in gutters/roof drains, but is contaminated when it falls on the ground instead of into a tank. For irrigation all that is necessary is to soak the rainwater in as soon as possible to prevent evaporation and runoff, since potability is not a requirement. This is even cheaper than rooftop catchment. Of course you may need to re-green the upwind deserts first (since ~80% of terrestrial rainfall comes from plants, not evaporation), but we already have that technology. http://www.youtube.com/watch?v=K1rKDXuZ8C0 http://www.youtube.com/watch?v=K1rKDXuZ8C0 This is hardly unprecedented. The CCC installed thousands of miles of swales during the Depression (that function to this day), but nowadays most people don't even know what a swale is.

moocowduckquack 13y ago
How is this better than local rainwater collection? It works when there is no rain without needing a tank big enough to last a several year long drought. The architecture of the greenhouse acts as a solar desalinator that in testing creates more water than is needed to irrigate the plants, so it not only grows plants, but also can provide clean water in the desert.
- Zancarius 13y ago
  I find it curious that on HN of all places, there are some who seem appalled that technology could be used to offset much of what we've done, largely as a fault of technological advancement. That's not to say I'm against conservation. I think conservation is a necessity that few appreciate (having lived in a desert all my life, I have a certain appreciation for scarce resources), but comments like the one you replied to are exactly the kind we don't need. That is, dismissal of alternate solutions isn't going to help the problem get any better. Out here, there's a large, untapped reservoir of brine that would be ample water to supply the neighboring communities for decades or more. The local government continues to humor bonds to build a desalinization plant every 10 years with conditions that the money will be redirected after 3 years if the plant isn't built, and unsurprisingly, the plant is never built. These greenhouses, if they work, would be a worthwhile experiment and probably substantially cheaper considering the wider variety of crops that could be grown and sold. Not to mention local growers could continue growing their crops without ruining the freshwater wells of their neighbors by running them dry. I just doubt it'll happen until the cost of pumping fresh water becomes too expensive or the wells are run completely dry.
  - schiffern 13y ago
    >comments like the one you replied to are exactly the kind we don't need. GP here. :) I'm 100% in favor of using technology "to offset much of what we've done, largely as a fault of technological advancement." After all, rainwater collection is technology! But desalination isn't that kind of technology — it's the destructive kind. My question was genuine. What advantage does plastic greenhouse desalination have over rooftop rainwater harvesting? It uses less land. It costs less. It produces less pollution. No piped distribution to tear up the streets for every 50 years. No energy needed to pump water long distances. The only advantage I can see is that under desalination, someone gets to control your access to water. Advantageous for them I mean.
    - Zancarius 13y ago
      > But desalination isn't that kind of technology — it's the destructive kind. But is it really? You're effectively doing what occurs in nature. Clearing land and building a distribution infrastructure is destructive, but certainly no more than what is already going to happen regardless of whether or not desalinization is used. Pumping from salt water aquifers might qualify as well. > My question was genuine. It was, but your comment seemed dismissive of alternatives. I don't think that objectively adds anything to the conversation. I apologize if that wasn't your intent. I can see a solar desalinization system in place in areas where much of the water you encounter underground is brine or otherwise non-potable, and it's particularly useful in areas where other methods of collection won't work. Yes, it has the potential drawback of kicking the can farther down the road in terms of potentially extracting water faster than it's replaced. But that said, in much of the west, the topography lends itself well to draining much of the run off into large basins and water ingress likely far outpaces whatever could be pumped out of the ground. Perhaps a hybrid (rainfall collection + solar desalinization) would be ideal. I think you're focusing exclusively on the advertised "seawater greenhouse" and may not be aware of the benefits such a design would have in areas where there certainly is plentiful salt water, just not from a sea.
      - deleted 13y ago
        [deleted]
- schiffern 13y ago
  > big enough to last a several year long drought You're way overestimating the size needed. Even in drought years there is substantial precipitation, but generally it happens at the wrong time of year. Often you'll have flooding in the same year as drought! See this recent example: http://news.nationalgeographic.com/news/2013/09/130913-colorado-flood-boulder-climate-change-drought-fires/ http://news.nationalgeographic.com/news/2013/09/130913-color... That flooding is made worse by hardware (meaning roofs, concrete, etc) that prevents infiltration and overwhelms surrounding areas. It's often cheaper to oversize your catchment area and direct tank overflow to a nearby garden. Generally the available roof area isn't the limiting factor, but I encourage you to verify this by looking up annual rainfall numbers for areas you're interested in. Do you know how much rain falls on your roof each year?
crusso 13y ago
nowadays most people don't even know what a swale is crusso raises his hand then goes off to google.
- GFischer 13y ago
  Me too, you always learn something new :) http://en.wikipedia.org/wiki/Swale_(landform) http://en.wikipedia.org/wiki/Swale_(landform)
  - angersock 13y ago
    Wow, it's like Houston personified.
huherto 13y ago
Amazing, I want to believe. This is such a big problem in my home town in northern Mexico/American southwest.

bjelkeman-again 13y ago

I spent years volunteering with Seawater Greenhouse and Charlie Paton, the inventor, including working in one of the pilot plants in Australia for a short while. They are very interesting technology and if I wasn't working on the organization I am working on now I would probably be working with a large scale Seawater Greenhouse installation somewhere today.

moocowduckquack 13y ago
That is really good of you. Massive amounts of respect. Out of interest, what is it you are now working on? edit - I just had a look at what you are doing through your username, akvo looks pretty cool.
- bjelkeman-again 13y ago
  Thanks! We try.