Fig. 2. An energy transformation hierarchy adapted from Odum (1996:23). (A) Spatial view of units and territories, (B) energy network including transformation and feedback, (C) aggregation of energy networks into an energy chain, (D) bar graph of energy flows for the levels in an energy hierarchy, and (E) bar graph of emergy (energy memory) flows for the levels in the same hierarchy. The emergy flow is the same for each pathway, but the energy flow decreases at each step.