Re: SC93

http://thearchdruidreport.blogspot.com/2009/06/thermodynamic-economy.html

The Thermodynamic Economy

........Only a few economists at the time, and even fewer since then, realized that these perplexities pointed to weaknesses in the most basic assumptions of economics itself. E.F. Schumacher was one of these. He pointed out that for a modern industrial society, energy resources are not simply one set of commodities among many others. They are the ur-commodities, the fundamental resources that make economic activity possible at all, and the rules that govern the behavior of other commodities cannot be applied to energy resources in a simplistic fashion. Commented Schumacher in Small is Beautiful:

“I have already alluded to the energy problem in some of the other chapters. It is impossible to get away from it. It is impossible to overemphasize its centrality. [...] As long as there is enough primary energy – at tolerable prices – there is no reason to believe that bottlenecks in any other primary materials cannot be either broken or circumvented. On the other hand, a shortage of primary energy would mean that the demand for most other primary products would be so curtailed that a question of shortage with regard to them would be unlikely to arise” (p. 123).

If Schumacher is right – and events certainly seem to be pointing that way – at least one of the basic flaws of contemporary economic thought comes into sight. The attempt to make sense of energy resources as ordinary commodities misses the crucial point that energy follows laws of its own that are distinct from the rules governing economic activities. Trying to predict the economics of energy without paying attention to the laws governing energy on its own terms – the laws of thermodynamics – yields high-grade nonsense.

Look at the way that rules governing the availability of other resources go haywire when applied to energy. When North America’s deposits of high-grade iron ore were exhausted, for example, the iron industry switched over to progressively lower grades of ore; these contain less iron per ton than the high-grade ores but are much more abundant, and improved technology for extracting the iron makes up the difference. In theory, at least, the supply of iron ore can never run out, since industry can simply keep on retooling to use ever more abundant supplies of ever lower-grade ores, right down to iron salts dissolved in the sea.

Try to do the same thing with energy, by contrast, and two awkward facts emerge. First, the only reason the iron industry can use progressively lower grades of ore is by using increasingly large amounts of energy per ton of iron produced, and the same rule applies across the board; the lower the concentration of the resource in its natural form, the more energy has to be used to extract it and turn it into useful forms. Second, when you try to apply this principle to energy, you very quickly reach the point at which the energy needed to extract and process the resource is greater than the energy you get out the other end. Once this point arrives, the resource is no longer useful in energy terms; you might as well try to support yourself by buying $1 bills for $2 each.

This difficulty can be generalized: where energy is concerned, concentration counts for much more than quantity. That’s a function of the second law of thermodynamics: energy in a whole system always moves from high concentrations to low. Within the system, you can get energy moving against the flow of entropy, but only at the cost of reducing a larger amount or higher concentration of energy to waste heat. That’s how fossil fuels came into existence in the first place; the vast majority of hundreds of millions of years of energy from sunlight falling on prehistoric plants were degraded to waste heat and radiated into outer space, and in the process a very small fraction of that sunlight was concentrated in the form of carbon compounds and buried underground.

The same rule of concentration explains a great many things that current economic ideas miss. Consider the claims made every few years that we can power the world off some relatively low-grade energy source. Latent heat stored in the waters of the world’s oceans, for example, could theoretically provide enough power for the world’s economy to keep it running for some preposterously long period of time, and any number of inventions have tried to tap that energy. They’ve all failed, because it takes more energy to concentrate that heat to a useful temperature than you get back from the process. The same is true a fortiriori of “zero point energy,” the energy potential that according to current physics exists in the fabric of spacetime itself. It doesn’t matter in the least that there’s an infinite amount of it, or something close to that; it’s at the lowest possible level of concentration, and thus utterly useless as a power source for human society.

The same limits apply, if less strictly, to many of today’s renewable energy sources. Solar energy, for example, is very abundant, but it’s also very diffuse. As with any other energy resource, you can concentrate some of it, but only by letting a larger quantity of it turn into waste heat. It’s quite common to hear the claim that because solar energy’s so abundant, our society can easily power itself by the sun, but this shows a failure to grasp thermodynamic reality. Today’s industrial societies require very highly concentrated energy sources; our transportation networks, our power grids, and most of the other ways we use energy, all work by degrading very high concentrations of energy all at once into waste heat, and without those highly concentrated resources, those things won’t work at all.

Now of course there are plenty of productive things that can be done with more diffuse energy sources. Once again, solar energy provides a good example. Passive solar heating for buildings is a mature and highly successful technology; so is solar hot water heating; so are a good many other specialized uses, such as using solar ovens for cooking, water purification, and the like. All these can contribute mightily to the satisfaction of human needs and wants, but they presuppose very different social and economic arrangements than the centralized energy economy of power plants, refineries, pipelines and power grids we have today. As concentrated energy from fossil fuels becomes scarce, in other words, and more diffuse energy from the sun and other renewable sources has to take up the slack, many of the ground rules shaping today’s economic decisions will no longer apply.

What this implies, in turn, is that economics does not exist in a vacuum. The ground rules just mentioned took shape, after all, in an age where economic processes were dominated – one might even say “distorted” – by our species’ temporary access to extravagant supplies of cheap and highly concentrated fossil fuel energy. The new ground rules of economics that will take shape in the twilight of the age of cheap energy, in turn, will be shaped by the fact that energy is once again scarce, costly, and diffuse. More generally, it’s necessary once again to pay attention to the myriad ways that human economic systems are rooted in the wider processes of the natural world........