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Providing freshwater to those in need. A plan for economical stability in third world countries.

My idea is to create low-tech and low cost desalination (desal) plants in arid climates in close proximity to the ocean. These desalination plants would operate by harnessing solar energy to heat the saltwater, with outputs of fresh water and salt. The desal plants would be located near the ocean, and would be simple, shallow pools lined with a black pond liner. There would be a green house cover over the pool to capture the water vapor, which would travel through a hose which leads to collection tanks. The greenhouse cover is necessary not only to keep the humidity contained, but also heats the saltwater, speeding up the evaporation process. Saltwater would be pumped to the pools (desal plant) by wave turbines, or a more cost-effective option would be a hand pump, pedal powered pump, RAM pump etc. These desal plants would be cheap to create and run, needing little upkeep, and would help to curb sea level rise while providing freshwater where needed. Optional: Parabolic reflectors aimed at pools.

A step further: Use the freshwater to help reverse desertification.
These steps would require further "nurture capital" to help end hunger and fight poverty. Community Centers (CCs) would be built near the desal plants. The CCs would provide freshwater and composting toilets at the bare minimum. The humanure from the composting toilets would be used to grow jatropha plants. Jatropha, which thrives in arid conditions and poor soil and is drought resistant, was cited by Goldman Sachs as one of the best candidates for biodiesel production. Jatropha seeds would be collected by the villagers, and the CC would serve as a drop-off location. The CC would purchase the seeds from the villagers, and the villagers would then be able to buy groceries from the CC. This system would create a full cycle economy complete with global commodities (biodiesel and seasalt). Deciduous and wildlife activity with adequate aquifers would help reclaim land lost to desertification and restore topsoil

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    Jun 21 2013: Sketch it up Michael Carey! Draw a schematic of the simplest kind showing each major step in the process as described above. List the main benefits, challenges, and recognized TBD's (to be determined) and any likely unknowns. Accumulate cost estimates based upon existing projects. Document E V E R Y T H I N G in an indexed journal with time, date, and initials. Think about a downsized, family-sized, self-contained, portable system. Good on ya, mate!
  • Jun 22 2013: There are already desalination plants Also, on a ship fresh water is produced by its generators. But there is salt or super-salty water to dispose of if you desalinate ocean water. Is that really a good idea?
    • Jun 22 2013: The ocean is currently being diluted and therefore the percentage of salt in the water is decreasing. Salt levels lowering in the ocean is destructive, as it slows the movement of the water down and I'm sure causes potential issues with oceanic life. However, taking water out of the ocean does not so much decrease the percentage of salt in the water, it reduces the seawater wholly. Additionally, I think it could have lots of positive effects on the ecosystem as a whole. By increasing the availability of freshwater in arid areas, you are helping to raise the aquifer. If many of these desal plants were used in tandem it might create enough of an impact to replenish the aquifers, and encourage plant and wild life to grow in desertified areas. This would in turn increase the amount of rainwater that wouid be absorbed by the land. More vegetation would absorb more rainwater which would decrease runoff and rapid evaporation of arid soil. This effect would likely raise the levels of salt in the ocean by increasing global absorption of rainwater and decreasing runoff. Also increased carbon sequestration by the plant life would help to lower CO2 levels in the atmosphere. Instead of collecting the sea salt, another option would be to pump the brine back into the ocean, which is currently done with treated wastewater (another way salt levels in seawater are depleted).

      The problems with current desalination plants are that they are both energy and capital intensive. This is an economically feasible and eco-friendly way to help curb sea level rise, decrease CO2 levels, reverse desertification and solve the issue faced by many people today and many more tomorrow, acquiring clean drinking water. People are currently mainly relying on wells for fresh water in many areas, specifically those that are desertified or are facing desertification. Excessive use of wells will ultimately deplete the aquifer and speed desertification.
      • Jun 23 2013: I didn't know that,but I read that there are local salinity issues near some of the big plants.
  • Jun 21 2013: Pond Liner 70' x100' - 2100$
    Green House Cover 70' x 100 - 877$
    200' PVC pipe - 240$
    Water tank 305 gl - 225$
    Flex PVC pipe 25' -50$
    Salt water pump -200$
    Solar Panel Setup -500$
    Total Cost - 4192$
    Hand pump (No solar panels) -39$
    Total Cost - 3256$

    Optional: Mylar for homemade reflectors (50"x25') - 22$

    Miniature Desal Plant-
    Pond Liner 7'x 10' -39$
    Green House Cover 8'x10' -29$
    Clear Vinyl Tubing 8' -6$
    Total Cost- -74$

    No pumps used, water transferred by hand. Freshwater collected in 5 gal bucket w/ lid and spout.

    EDIT: The use of the black pond liner is optional
    Pondliner Pros- black color absorbs heat,
    -keeps water from absorbing into the ground.
    Cons-doubles the price of the desal plant.
    -would need to pump more water, due to absorbtion into the ground.
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      Jun 21 2013: Build one and demo it with free drinks of pure, fresh water! You have done much invisible labor, now do some visible labor (Victor Hugo). Find energy in the difficulties you face. Do it, Lad, do it! (Keep us posted).
    • Jun 25 2013: Hi Michael,

      I would be very interested in the development of this project.
      Please keep me informed of your progression.