First Principle Land Requirements to Feed a Person: Difference between revisions
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A person uses 100w of energy. | A person uses 100w of energy from food. [http://sustainability.blogs.brynmawr.edu/2012/07/31/understanding-energy-part-1/]. The sun shines 1000W per sq meter, and plants such as duckweed convert 1% (chemical), or about 10x less than PV panels (electric). Duckweed captures thus 10W per square meter. Tilapia eat duckweed, so that gets energy down to .1% conversion efficiency at conservative estimates. | ||
If duckweed gets 10W per meter squared capture - we need 10 sq m or 1/400 acre. Very promising. The fish there are a trophic chain loss, so if we have another crop that produces at 1% - then 1/400 of an acre is sufficient to feed a vegetarian on first principle calculations - just for the carbohydrate. That is 100 square feet! | |||
Now fish are in principle very efficient converters of feed to body mass - so if that factor of loss is 50% at best, then the pescaterian requires 20 sq meters of land to feed them¡!!!!!!!!! | |||
Doomsday? I don't think so. | |||
Latest revision as of 12:43, 30 June 2016
A person uses 100w of energy from food. [1]. The sun shines 1000W per sq meter, and plants such as duckweed convert 1% (chemical), or about 10x less than PV panels (electric). Duckweed captures thus 10W per square meter. Tilapia eat duckweed, so that gets energy down to .1% conversion efficiency at conservative estimates.
If duckweed gets 10W per meter squared capture - we need 10 sq m or 1/400 acre. Very promising. The fish there are a trophic chain loss, so if we have another crop that produces at 1% - then 1/400 of an acre is sufficient to feed a vegetarian on first principle calculations - just for the carbohydrate. That is 100 square feet!
Now fish are in principle very efficient converters of feed to body mass - so if that factor of loss is 50% at best, then the pescaterian requires 20 sq meters of land to feed them¡!!!!!!!!!
Doomsday? I don't think so.