Here is an amazing paper by Dr. Mae-Wan Ho, Institute of Science in Society. Thermodynamics of Organisms and Sustainable Systems. The paper is pretty technical, but basically it shows how and why living organisms are “sustainable systems” from a thermodynamics perspective — and how to design sustainable communities that exhibit the same ‘anti-entropic’ characteristics.
I have developed a “thermodynamics of organized complexity” based on a nested
dynamical structure that enables the organism to maintain its organisation and
simultaneously achieve non-equilibrium and equilibrium energy transfer at maximum
efficiency (Ho 1993, 1998a, 2007a).
The healthy organism excels in maintaining its organisation and keeping away from
thermodynamic equilibrium – death by another name – and in reproducing and providing for future generations. In those respects, it is the ideal sustainable system (Ho, 1998b,c; Ho and Ulanowicz, 2005). Looking at sustainable systems as organisms provides fresh insights on sustainability, and offers diagnostic criteria that reflect the system’s health.
This paper formalises and updates the ‘zero-entropy’ model of organisms and sustainable systems, and shows how sustainable development is possible by explicit reference to a ‘zero-emission’, ‘zero-waste’ integrated food and energy ‘Dream Farm 2’.
The diagram is color-coded: red is for energy, green for food, black is waste in the conventional sense of the word, but is soon transformed into resources, and blue is for water conservation and flood control, a key requirement in stable food and energy production under the vagaries of rainfall patterns now experienced across the world.
The anaerobic digester is the core technology for treating wastes, preventing pollution and generating energy. Livestock manure, food, paper and other biological remains are fermented by naturally occurring waste-gobbling bacteria and turned into biogas, which provides much of the energy needs. The partially cleansed wastewater goes into the algal basins where algae photosynthesis produces all the oxygen needed to detoxify the water, making it safe for the fish.
The algae are harvested to feed chickens, ducks, geese and other livestock. The fishponds support a compatible mixture of 5-6 fish species. Water from the fishponds ‘fertigates’ crops growing in the fields or on the raised dykes. Fruits and vegetables can be grown in floats on the surface of the fishponds. Water from the fishponds can also be pumped into greenhouses for aquaculture of fruits and vegetables. The water, purified of nutrients, is returned to the aquifers. The anaerobic digester yields a residue rich in nutrients that is an excellent fertiliser for crops. It can also be mixed with algae and crop residues for culturing mushrooms after steam sterilisation. The residue from mushroom culture can be fed to livestock or composted. Crop residues are fed back to livestock. Crop and food residues can be used to raise earthworms to feed fish and fowl. Compost and worm castings go to condition the soil. Livestock manure goes back into the anaerobic digester, thus closing the grand cycle. The result is a highly productive farm that’s more than self sufficient in food and energy, and saves substantially on carbon emissions. Anaerobic digestion of livestock and other wastes saves carbon emissions twice over, by preventing the serious greenhouse gases methane and nitrous oxide from reaching the atmosphere, and by methane substituting for fossil fuel use to run vehicles and farm machinery.