As it happened with me when I first read the word emergy, I assumed a typographical error but a little digging into the internet searches led me to a vast source of information on a subject I had never heard of.
As wiki says it, “Emergy is an expression of all the energy used in the work processes that generate a product or service in units of one type of energy.” The study and understanding of emergy becomes important when the global energy, ecology and economy models are coupled.
Energy and money flow in opposite directions. When the concept of emergy or the embedded energy is taken into account, we have a much clearer view of the implications of this statement. For every monetary transaction that occurs, there is an exchange of energy in the reverse direction.
Keeping this in mind, the US goal of energy independence seems less likely. If no energy comes into US from the outside, it implies that no money flows outside of the US, essentially putting US out of the global trade map. Even if we were to equate US energy independence simply with no use of middle east oil, it would still be a far-fetched dream. Even though US itself does not choose to import any middle east oil, it will still have trade relations with countries that do so. So, with emergy analysis in place, US is still importing middle east oil. Though we have recent developments that seem to address this issue (sanctions on Iranian oil imports by all countries), it still remains to be seen how much can US influence the third-party trade relations of other countries.
Growth and consumption
The Darwin-Lotka energy law states that there is an evolutionary advantage to organisms that maximize energy flow. There is ample evidence to show this. Considering the energy – money equivalence, it can historically be seen that the trade centers have prospered. However, the downside to this comes from the fact that money is circulated while energy is not, when we consider the human subsystem of the total ecosystem. The following figure shows an energy and money flow diagram where the dotted lines denote money flow and the solid lines denote energy flow.
So, a logical question props up: if energy is being lost in every transaction, is the growth that we see today sustainable without the use of renewable resources? A study shows that to continue on a growth trajectory, changes need to be made to the present energy consumption pattern, and they need to be made sooner. The following graphs give a clear picture:
Thus it can be seen that the knowledge of emergy and the study of coupled energy, ecology and economy models is central to policy decision making.
Energy, Ecology, and Economics, Howard T. Odum, Ambio 1973 (http://www.jstor.org/stable/4312030)
Sustainable Development of Energy, Water and Environment Systems. N Vol. III, Naim Afgan & Neven Duic, Proceedings of the 3rd Dubrovnik Conference, Dubrovnik, Croatia, 5-10 June 2005
Culture of Ecology: Reconciling Economics And Environment, Robert E. Babe, University of Toronto Press, 2006
The Whole Earth Catalog (http://www.wholeearth.com/index.php): My starting point for this topic. This is the same one from where Steve Jobs borrowed his famous quote “Stay hungry, stay foolish”