Packaged foods contain the note “Based on a 2,000 calorie-per-day diet.” (They mean kilocalorie, but that is another story.) This “calorie-per-day energy” can be stated as the steady-state use of 100 watts. But to get this energy to us (fertilizer, refrigeration, distribution, etc.) requires another 900 watts. The rate of energy use needed to feed each of us in the U.S. is about 1 kilowatt.