Entropy (not Energy) is the Issue

According to the Conservation of Energy Principle, we can neither create nor destroy energy. This means we will always have as much energy as we ever had. So, how can we experience an energy crisis?

Our crisis develops from another law of energy: The Entropy Law. It states that energy use always results in some overall loss of availability, quality, or order. Physics characterizes such loss as an increase of entropy. This is where informed energy discussions begin.

The inevitable increase of entropy seems to have a slightly different character for each system under consideration. For example, heat always flows from the hotter to the colder body, never the reverse. Perfume molecules escape their container and spread throughout the room, but never gather back into the bottle of their own accord.

While heat is flowing, or perfume molecules are spreading, they can do work—they are useful. Even after heat flows down its temperature hill, or the molecules spread out in a room, overall energy remains constant, but that energy is now unavailable for use--no good for doing work.

Entropy applies thermally, structurally, and environmentally. Just as a weight cannot supply any mechanical work once it reaches its lowest available level, thermal energy is not available for use after it falls to an ambient temperature. It simply becomes ‘waste’ heat, like car exhaust. Entropic disorder is commonly termed pollution.

There are various mathematical expressions for Entropy, such as S = k ln W (where k is a constant and W is the microstates per macrostate). Due to its broad, complex, and abstract formulations, some have rejected the Entropy Law—even deemed it an illegitimate natural principle because too ‘anthropomorphic’ (as if scientific laws had any other origin). Einstein, however, thought the Entropy Law was the one law that would never be overthrown.

Some have said that life transcends the Entropy Law, but no contradiction exists since the overall Entropy increase (system plus surroundings) still exceeds the entropy decrease of a structuring organism.

By extension of the Entropy Law, matter also becomes unavailable for use. High entropy copper junk (because dispersed in refuse dumps) can be too costly to recycle, both monetarily and environmentally, thus practically unavailable. Entropy’s economic decrements are developing beyond the control of today’s price mechanisms.

From an entropy perspective, economic growth is the progressive transformation of usable energy into unavailable energy. This means an overall decline in our environment—except that the sun’s outside gift of energy may compensate for this decline by driving the earth’s large-scale regenerative cycles (carbon, oxygen, etc). The sun’s finite input, however, can only compensate if economic activity’s entropy production is not too large.

All large-scale technical fixes such as ‘clean’ coal, nuclear, or corn-ethanol create quality (entropy) issues. Energy from coal results in acid rain, global warming, methyl mercury in food chains, and toxic, congesting particles in the air we breathe. Nuclear plants create radioactive waste in direct proportion to the energy produced—some of which (Plutonium 40) requires environmental isolation for hundreds of thousands of years. Nuclear decommissioning costs billions. Corn-ethanol production emits two to nine times the greenhouse gas emissions ‘saved’ by substituting it for gasoline.

Because of the high environmental costs we pay for creating high-quality (low entropy) energies such as electricity or hydrogen fuel, we should use them only where their quality is truly necessary. Coal-electric space heating and plug-in cars remain prohibitive.

The Entropy Law sets limits to the types of energy use humans can sustain. Since all earth-energized technological orderings result in an overall loss of order (even for pollution control devices and recycling), entropy compensating sources of energy must be external. Practically, this means the sun. Non-solar energy solutions become ‘uneconomic’ (if not snake oil) once price mechanisms factor in their entropy effects.

We can choose to assess and respect the Entropy Law’s implications, or we can continue to make energy policy in ignorance. A mix increasingly weighted toward low entropy solar applications is finally unavoidable. Reversible entropy is not merely a tree-hugger’s fancy; it is an ecological necessity.

For many energy applications, we have yet to determine the form, let alone the cost, of their attendant entropy (disordering). In the very big picture, however, specific calculations (the details) don’t matter. According to the entropy law, we either go (relatively direct) solar or decline.

A mathematical interpretation follows: The Entropy Law (Second Law of Thermodynamics) when applied to an overall system undergoing an irreversible (practical) energy exchange and consisting of a subsystem of interest in equilibrium with its surroundings is expressed mathematically as

dS(overall) = dS(subsystem) + dS(surroundings) > 0

where dS is the attendant change in entropy.

The surroundings are taken large enough to form an unlimited reservoir. Thus, equilibrium is maintained with the system of interest. The above mathematical inequality states that the overall, proximate change in entropy (subsystem plus surroundings taken together) for any practical energy exchange is always positive. In other words, all earth-alone energy exchanges result in a net disorder.

Should external (solar) energy enter the overall system, the mathematical inequality may no longer hold. The net entropy can be zero or even negative. In other words, inputs of solar energy can compensate the otherwise inevitable entropy increases of our energy exchanges.

Here are a few examples of how an entropy-oriented analysis might expeditiously cull out technological proposals.

Aren’t hydrogen-fueled cars ‘ecological’ since they emit only pure water? An entropy analysis cuts immediately to whether a solar component is involved. If no solar component exists to negate the entropy that attends hydrogen production, storage, and handling, the overall effect is ecological degradation. Note the economy of approach here. An entropy analysis doesn’t need to show precisely how the degradation manifests to declare it unecological.

‘Clean’ coal combustion is similarly dismissible. If coal’s CO2 (greenhouse) by-product could be dumped (‘sequestered’) without ecological consequences, the entropy law would be violated thereby making the whole science of thermodynamics incomprehensible.

Isn’t nature’s geothermal energy, if unused, simply wasted? This question is superficial because it deals only with energy. The relevant question is: Does geothermal have entropy negation (a solar component)? If not, it is unecological. From an entropy perspective, we don’t need to employ a team of engineers to investigate whether geothermal’s accelerated cooling of magma releases ‘too much’ CO2 to sequester. CO2 waste dumps aren’t ecological. If an energy project is purely earth-derived (no solar negation), it provides no ecological solution.

Of course, minor solar entropy compensations soon wash out among infrastructure, transportation, and other supporting technologies. This means our solar applications must be relatively direct (wind, solar panels/concentrators, possibly hydro, etc.).

Some may still cling to the idea of ‘affordable decline’. But keep in mind, most entropy effects ultimately manifest as waste heat. Here, we are up against our ecological limits. Global warming makes this abundantly clear. We can no longer settle for lesser evils.

Summing up, our only practical means of negating technology’s inevitable entropy (eco-degradation) is solar incorporation. No solar, no sustainability, no ecological solution. Go solar or decline!