The Physics of Energy and the Economy

I approach the subject of the physics of energy and the economy with some trepidation. An economy seems to be a dissipative system, but what does this really mean? There are not many people who understand dissipative systems, and very few who understand how an economy operates. The combination leads to an awfully lot of false beliefs about the energy needs of an economy.

The primary issue at hand is that, as a dissipative system, every economy has its own energy needs, just as every forest has its own energy needs (in terms of sunlight) and every plant and animal has its own energy needs, in one form or another. A hurricane is another dissipative system. It needs the energy it gets from warm ocean water. If it moves across land, it will soon weaken and die.

There is a fairly narrow range of acceptable energy levels–an animal without enough food weakens and is more likely to be eaten by a predator or to succumb to a disease. A plant without enough sunlight is likely to weaken and die.

In fact, the effects of not having enough energy flows may spread more widely than the individual plant or animal that weakens and dies. If the reason a plant dies is because the plant is part of a forest that over time has grown so dense that the plants in the understory cannot get enough light, then there may be a bigger problem. The dying plant material may accumulate to the point of encouraging forest fires. Such a forest fire may burn a fairly wide area of the forest. Thus, the indirect result may be to put to an end a portion of the forest ecosystem itself.

How should we expect an economy to behave over time? The pattern of energy dissipated over the life cycle of a dissipative system will vary, depending on the particular system. In the examples I gave, the pattern seems to somewhat follow what Ugo Bardi calls a Seneca Cliff.

Figure 1. Seneca Cliff by Ugo Bardi

Figure 1. Seneca Cliff by Ugo Bardi

The Seneca Cliff pattern is so-named because long ago, Lucius Seneca wrote:

It would be some consolation for the feebleness of our selves and our works if all things should perish as slowly as they come into being; but as it is, increases are of sluggish growth, but the way to ruin is rapid.

The Standard Wrong Belief about the Physics of Energy and the Economy

There is a standard wrong belief about the physics of energy and the economy; it is the belief we can somehow train the economy to get along without much energy. Continue reading