Build a dam and in a few centuries its reservoir will be completely full of silt.
Furthermore, that silt will not simply fill the space that was taken by the water when the reservoir first filled. It will back up far upstream, because it must create a slope for the river to flow down. Water flows downhill. No hill; no flow.
The men who built the dam had their reasons for tapping into the flow of water, but Mother Nature has her say about that flow, too. The builders will speak of "energy" when giving their reasons, and they see a picture of the Sun flooding Earth with radiant energy which evaporates water in the oceans, lifts the water vapor to great heights so that it may fall on the mountains and flow from the mountains downhill to the seas. "The Sun is our source of life-giving energy," they will say. "It's there for the tapping."
But Mother Nature sees something a little different. She hangs around for so long, compared with that man who decided to construct the dam, that the man isn't even a minor itch for her to scratch. That water flowing from mountains to seas is a sculptor's carving tool. She is the sculptor, and the silt is the waste product of her sculpting. The man with his dam taps something he only partially understands—and then impetuously reacts in his myopic vision of time and his simplistic notion of what he calls "energy."
It's a shame.
The Sun is not "The Source of our energy." Some wise men of the mid-nineteenth century discovered that fact, taught it to the rest of us, but too few of us understood what we learned. That energy which flows from Sun to Earth to water to clouds to rain to rivers, etc. doesn't stop flowing. It will eventually flow out into the vast cold of outer space. Exactly as much energy flows from Earth to outer space as flows from the Sun to Earth. We don't tap that flow with our dams so we can "use it up." Energy cannot be destroyed—nor can it be created. That was one of the discoveries of the mid-nineteenth century. It is a discovery that remains rarely understood at the beginning of the twenty-first century. Not really understood.
So the dam builder makes statements like,
"I think it's a shame that we haven't developed every single possible kilowatt
from this renewable, non-polluting source of
Waste products are unpleasant, and man prefers to forget about them. Does forget about them. Waste products are a complicating factor adding to man's problems, and man likes to think about only one problem at a time. Perhaps can't handle more than one at a time. And so, only a handful of men have seen the significance of the insight of one mid-twentieth century wise man, Erwin Schrödinger. That "thing" so important to us in food, important to us in fuel for our engines, that thing we call "energy," is the removal of "wastes," and more insightfully, is the removal of what those wise men of the mid-nineteenth century called "entropy."
"What then is that precious something contained in our food which keeps us from death? That is easily answered. Every process, event, happening—call it what you will: in a word, everything that is going on in Nature means an increase in entropy of the part of the world where it is going on. Thus a living organism continually increases its entropy—or as you might say, produces positive entropy—and thus tends to approach the dangerous state of maximum entropy, which is death. It can only keep aloof from it, i.e. alive, by continually drawing from its environment negativeThe source of negative entropy (what we usually call "energy") is not simply the Sun. It's the whole system that starts with the heat from the Sun and ends up with the "waste removal" provided by the cold of outer space. The dam builder's big mistake is seeing too small a piece of the world. It's a mistake that leads virtually everyone in the twentieth century to anthropocentrically see "energy" as like the food we consume.
So today we see Mother Nature continuing her task
as sculptor, as always relying on the inexorable waste removal of the flow
of energy from Sun to Earth to outer space. She remains completely
confident that pozzolan-planting man will be no more than a momentary itch
as he naively blocks that flow to temporarily collect the wastes of her
sculpting in his proud silt baskets. Desert
dams are Gila monsters, Moki steps to future disaster.
It's a shame the dam builders did not see Schrödinger's insight.
is the capacity to do work" writes the textbook writer. Then, a few
chapters later, he writes, "Energy can be unavailable for doing work."
is frequently not what it seems at first to be. Often the simpler
the science, the more subtle it is.
simpletonisus," a persistent, pervasive infection of our perceptions
of the world. It's much easier to consider just one thing at a time,
but that usually leads to "solutions" that are superficially attractive
and ultimately disastrous.
subtle science caused Schrödinger to reject
energy as being "that precious something contained in our food which
keeps us from death"?
turned Feynman into a "volcano," according to his wife, and as described
Surely Your Joking Mr Feynman?
did he find a plethora of persistent, pervasive,
pernicious, pre-scientific, predictable, preposterous errors?