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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: 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.

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