Saturday, November 22, 2014

Sustainable world for everyone: Trying to define what's needed and working backwards - Water & Food

Water need is 50 liters per person per day, maybe 100.  20 for sanitation, maybe 40 (http://pacinst.org/wp-content/uploads/2012/10/basic_water_requirements-1996.pdf).  5 for drinking, 5 to 70 for bathing, 10 to 50 for cooking.  Assume all goes through waste-water treatment.  Ecological waste-water treatment (http://livingmachines.com/About-Living-Machine.aspx) can recycle 95%, so there's 5 liters per person per day of "fresh" water needed, rest can be recycled.  100,000 liters per day (1-2,000 people) costs $40,000 plus $16,000 per year in energy costs (assume that's 100,000 kwh per year) (http://livingmachines.com/Services/White-Papers/Lohan-et-al-2011.aspx).  Not clear how much acreage is involved.

Survival diet (work up from there):  1 cup of red lentils per day:  760 calories (http://www.bobsredmill.com/red-lentils.html), and guess 500 kwh to cook (see rice below).
2 cups brown rice  1370 calories and maybe 1,000 kwh to cook (water included above) - http://www.ideasrilanka.org/PDFDownloads/energy%20for%20cooking.pdf.  Again, not clear how much acreage is involved yet.

So far, for food and water, we're at 1500*365.25 = 547,875 + 1000 kwh per person plus an unknown amount of acreage and 5 liters/day of "fresh" water.  We'll work on acreage, capital plant, and the other basics:  clothing, shelter, and the most speculative:  fabrication.  Then I'll arbitrarily try to scale to Plato's 5040 population size, and try to build in ranges for climate, etc.

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