機械化
↑ IC Engine 20% efficient
↑ Electrical engines at 90% efficiency
↑ http://www.mwcog.org/uploads/committee-documents/v1ldW1s20060524145809.ppt
↑ Fuel cell efficiency
↑ 1 liter of fuel yielding 100 arms for 24 hours, when effiency is 40% which is never
↑ Combined work capability of human vs machines