In Item 2 of "Some Important Components of the Energy-Invested Term that Are Generally Neglected" (Dec. 6), I imply without proof or explanation that the repositories of materials needed for the main process under investigation and the essential ancillary processes can be maintained at their original levels. I wrote as though the recycle problem had been solved and a steady state could be achieved without further ado. That is not the case. Recycling the material in the infrastructure is a tricky business. More research is needed. Here is what I wrote to the critic who raised that point and, in addition, was concerned about the effects of friction:
Friction is not a problem. In general, the principal effect of friction is overcome by pushing harder. Let us weigh an engine with serious friction, like the gas turbine on a 747, when it’s brand new and after it is ready to be replaced. I would be surprised if the difference were appreciable. I am under the impression that the slight loss of material will not affect sustainability.
In other cases, the problem should be categorized as follows: (a) Separate the materials that we require to carry out the activities we consider important to our civilization, i. e., the materials we need to produce food and clothing, maintain shelter, provide health care to a stable or shrinking population, and provide art, music, literature and a few luxuries to take the drudgery out of life, e. g., computers; (b) divide the useful materials into two categories: (b1) the materials that can be recycled and devise the most energy efficient techniques to recycle them; (b2) find substitutes for the materials that cannot be recycled in any way, shape, or manner. (Remember that, even if only the elemental species can be recovered, the original substance can be synthesized at the expense of our supply of available energy (enthalpy minus the lowest temperature reservoir to which waste heat can be rejected times the entropy).)
I expected that a critic might nail me on recycling pharmaceuticals. I gave it a lot of thought. For now, I am satisfied that urinating on the ground might have to be forbidden. This was done by the Freemen on Frank Herbert’s Dune, a Desert Planet. Useful chemicals can be extracted from sewage by chromatography, for example. Materials that are deemed essential and for which no practical method of recycling has yet been found will remain a challenge for the time being. But, isn’t it a shame that I can’t write the University of Michigan and explain why this would make a relevant research topic. Since I am an alumnus, they should listen. But, not even a million dollar gift would be an incentive to deviate from the corporate agenda or violate the received wisdom from the ruling class.