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The table itself
September 4, 2012 - 6:18am

Due to technical difficulties beyond my control, my previous post about a table of energy inputs and outputs for various forms of food production contained description and discussion, but not the table itself.  If you're reading this, those difficulties have been resolved.  (If you're not reading this, please leave a comment and explain!)

So here it is:

Energy accounts for food production
  Hunting and gathering Pre-industrial agriculture Industrial agriculture
Labor 0.37 5650 20
Animal   960  
Machinery   230 18,590
Fertilizer     11,660
Pesticides     1090
Drying     4480
Irrigation     29,620
Total input 0.37 6840 64,460
Output 2.90 281,100 84,120
Output/input ratio 7.8 41.1 1.3
Output/human input ratio 7.8 49.7 4206.0

Inputs and outputs are in Mj per hectare per year.

Table copyright Michael Common and Sigrid Stagl.  Data from Energy and food production, Gerald Leach, IPC Press, 1975.



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