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Biogas or solar heat storage cooker for rural villages?

  1. Feb 9, 2019 #1
    Hello everyone,

    For villages in Africa and Asia that still use wood, dung or other biomass in simple stoves which option do you think will be better?

    Concentrate solar energy into an insulated unit with a molten salt which can then be used at any time or build a simple biogas generator (large scale or maybe even household) using rubbish, biomass, dung and maybe even human waste. With the second option you could also maybe help with the sanitation problem.

    There is also a third option of using much more efficient stoves so the current fuel they use will last longer and produce less smoke and particulates.

    Are there any other alternatives or ideas? Been thinking about this over the last few days and wanted some expert opinions. What would you do?

    Thanks for reading.
     
  2. jcsd
  3. Feb 9, 2019 #2

    jrmichler

    User Avatar
    Science Advisor

    It is not possible to design a good solution without extensive knowledge of the people, their customs and beliefs, their available resources (sun, digestible biomass, burnable biomass), economic payback, and available financing. You also need to match resources and needs. For example, how does the amount of methane from a human waste digester compare to the family's cooking needs?

    An example of a successful product is solar lights in poor areas without electric grid. Compared to kerosene lamps, solar is better light, much cheaper to own, and cleaner: https://cleantechnica.com/2015/05/12/solar-lights-eradicating-kerosene-lamps-africa/

    Check out Engineers Without Borders: https://www.ewb-usa.org/.
     
  4. Feb 11, 2019 at 8:45 AM #3
    Came across this interesting write-up saying that a bio reactor which exclusively ran on human solid waste wouldn't run due to the nitrogen content.

    http://large.stanford.edu/courses/2010/ph240/cook2/
     
  5. Feb 11, 2019 at 9:20 AM #4

    anorlunda

    Staff: Mentor

    I think there are very many attempts to do exactly what you propose. Your first step should be to research those earlier attempts. I suspect that just about every imaginable scheme has been considered.
     
  6. Feb 11, 2019 at 9:17 PM #5
    Check how much cloud cover they have, also what times of day they do traditional cooking, and how.
    { For silly example, compare temperature & time requirements for 'stir fry' & 'stew'... }
    Will they be able to prepare enough traditional meals in a sufficiently traditional way at traditional times ?

    Also, consider maintenance. IIRC, a lot of charities' drilled wells became unusable when their tool-kits and spares were sold, traded or stolen...
     
  7. Feb 11, 2019 at 10:20 PM #6

    256bits

    User Avatar
    Gold Member

    Still wondering what problem is being solved here.

    Is it the scarcity of dung and combustibles?
    Is it the time collecting dung and other combustibles?
    Which might imply a of foraging far from the village and entering into subsequent dangerous situations.
    Perhaps, since smoke and particulate matter is mentioned, the health and well being of the cook is being contemplated.
    Some solutions are not time savers nor effort savers nor cheap nor failsafe ( in regards to always being able to cook the food that day if the tech breaks down ).

    What do the villagers say?
     
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