21. Maximum Entropy Production by Technology

The dominant mode of entropy production enabled by the large-scale technological systems that power the world economy is the degradation of chemical energy in fossil fuels. One key parameter determining the rates of fossil fuel consumption and entropy production is the price of energy. The Rayleigh-Benard cell provides a laboratory analog in which, for a given driving force, the rate of entropy production is determined by the value of the thermal boundary layer thickness, whose inverse plays a role similar to that of price in large fossil fuel systems. In steady, serial systems like the diffusion-advection-diffusion Rayleigh-Benard cell or the oilfield-pipeline-city “technology cell”, an auto-control parameter like price or boundary layer thickness is required to coordinate spatially separated energy source and sink dynamics. For complex fossil fuel technologies the implicit and often unknown dependence of such control parameters on intrinsic system variables can hide internal constraints. If applied in the absence of knowledge of such constraints, the principle of Maximum Entropy Production (MaxEP) would yield, for sufficiently complex systems, an upper limit to rather than the actual value of the entropy production rate. Internal constraints on technology-enabled energy consumption, however, may represent only temporary hangups on the road toward a larger entropy production rate.