I appreciate the effort to analogize the economy as an ecology since the latter is, in the Gaia theory anyway, balanced in the long run with respect to energy and material flows.

But I think Colin raises a good point that needs to be considered. One major difference between the economy of humans and the ecology of Gaia is that in the latter the drive is from the lowest trophic layer. That is, what pumps energy into the system is the photosynthetic activities of plants and some bacteria. The higher trophic levels then dissipate the stored energy and the heat eventually re-radiates to space.

Animals do not demand food so much as simply consume what is present and when their numbers increase beyond the carrying capacity they die off or fail to reproduce to compensate. Hence the balance.

Humans do demand from above. They do want more and find ways to reroute energy flows, or in the case of fossil fuels to tap into the bank as it were, to serve their purposes. They invent the new ways to consume and expropriate energy production systems to provide what they want. There is no balance.

Except, perhaps in the long run. With the peaking of oil and gas production the energy bonanza is over and I seriously doubt that we will ever be able to replace it with alternative energy production systems. Then we will begin to see the similarities between the economy and the ecosystem. But we will also see the similarities between humans and all other animals faced with energy restrictions. That won't be a rebuilding of the economy. It will be what Richard Heinberg calls 'powering down' at best and chaos at worst. The latter seems like a high probability scenario to me in light of humanity, at the same time it is running on less gas, will have to cope with and adapt to the effects of climate change.

Regarding the production of energy: I loved Jon's description of the multi-tiered production system. In some of the work that I am doing at UWT (see my profile) I am building models of what I call the energy production sustainability criterion. Stated simply it says that any form of alternative energy production equipment, or what I call energy conversion capital, must produce sufficient energy to not only feed free energy to the end consumers, but must also feed back into its own maintenance and 'reproduction' cycle. That latter contribution may be minuscule in real-time, but it must cumulatively, over the working life of the unit, provide enough power to produce the next generation of conversion capital. And that includes enough power to produce the next generation of manufacturing plant and machine tools, etc. It remains to be seen that clean energy systems like photovoltaics and wind turbines will actually meet this long-range sustainability criterion.  

George
http://www.questioneverything.typepad.com

George Mobus, Associate Professor, Institute of Technology, University of Washington Tacoma, and Professional Student for Life

George --

I've wanted to create computer models of my ideas for a while now (here's a link to an SVG-based version of a start of a model, but you need Adobe's SVG add-in), and it sounds like you are moving in a similar direction, if I may be so bold.  I'd like to hear more about your work as you move forward (maybe a guest blog post?)

Back to reality, however, I was amazed that William Catton's 1980 book, "Overshoot", is still very relevant to today's problems.  This form of human civilization will certainly have to change, or it will experience overshoot and be changed.  However, I think that it is important to try to create positive "visions", or better yet, "models", of what a different civilization would look like, no matter how utopian the effort might seem now.  I think that Heinberg is sometimes too ready to give up on cities; he seems to think we will go back to villages and small towns, but I think that if we were to tackle our problems logically right now, cities would be a central part of the solution (I attempted sketch a city-centered solution here)

Keep going.

Steven Earl Salmony
AWAREness Campaign on The Human Population
http://sustainabilitysoutheast.org/

Please consider that the global human economy is an artificially designed, momentary, manmade construction, one that appears to be rapidly approaching a point in human history when endless economic growth will become patently unsustainable on the surface of a planetary home the size of ours. To the extent modifications in unbridled economic globalization are chosen by the managers of the human economy that adopt the workings of the sustainable economy of God's good Earth, then it will become sustainable, I suppose.

Steven Earl Salmony, Ph.D., M.P.A.
AWAREness Campaign on The Human Population
http://sustainabilitysoutheast.org/