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Entropy is the problem, not energy

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Wendell G. Bradley

Published February 16, 2008 at noon

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We can neither create energy nor destroy it. We will always have as much energy as we ever had according to the Conservation of Energy principle.

So, how can we experience an energy crisis? The crisis develops from another law of energy: The Entropy Law. It states that energy always suffers some loss of quality or availability during use. Physics characterizes this loss as entropy.

Increasing 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—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. It is no good for doing work.

Popular designations for Entropy’s inevitable increases are time’s arrow, disorder, or pollution. 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.

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) is too costly to recycle, both monetarily and environmentally, thus practically unavailable. Economic problems develop per the Entropy Law beyond the control of price mechanisms. From an entropy perspective, economic growth can be understood as the progressive transformation of usable energy into unavailable energy. This leads to an overall decrease in our living ability—except that the sun’s outside gift of energy may compensate for this decrease. 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 coal, nuclear, or ethanol create quality (entropy) issues. Energy from coal results in acid rain, global warming, methyl mercury pollution of fish, and toxic submicron particles in the air we breathe. Nuclear plants create radioactive waste in direct proportion to the energy produced—some of which (Plutonium 40) must be guarded in environmental isolation for hundreds of thousands of years. Ethanol production emits two to nine times the greenhouse gas emissions ‘saved’ by substituting it for gasoline.

In short, the Entropy Law sets limits to the types and rates of energy use humans can sustain. It, however, does not govern social phenomena. We can choose to assess and respect the Entropy Law’s implications, or we can continue to make energy policy in ignorance.

Because of the high environmental costs we pay for creating high-grade energies such as electricity or hydrogen fuel, we should use them only where their quality is absolutely necessary. Electric space heating and hybrid cars remain prohibitive.

Finally, technological orderings always result in a greater loss of order elsewhere. This applies to every application—even to pollution control devices and recycling. A mix increasingly weighted toward entropy compensating solar applications (renewables) is unavoidable. Renewables are not merely a tree-hugger’s fancy; they are an ecological necessity.

Wendell G. Bradley, Ph.D,a retired physics professor, lives in Windsor.

Comments

  • February 16, 2008

    5:19 p.m.

    Suggest removal

    CL writes:

    "We can neither create energy nor destroy it. We will always have as much energy as we ever had according to the Conservation of Energy principle."

    Nope. E=MC2 - energy = mass times the speed of light squared. Thats where the huge amounts of energy with fusion & fission come from - converting mass to energy.

  • February 17, 2008

    10:21 a.m.

    Suggest removal

    wfickas writes:

    The whole point of E=MC^2 is that mass and energy are equivalent. Mass is just energy in a dense form. The same entropy rule applies, but instead of chemical energy (which is the bonds between molecules) nuclear energy (the bonds between protons and neutrons) is converted to heat energy and ultimately dissipated as it is used to do work.

  • February 18, 2008

    7:19 a.m.

    Suggest removal

    VVVV writes:

    Nice smoke and mirrors. I like how your ultimate point of solar power does not include any of the entropy facts regarding its production. Even aggressive estimates put the payback (time to produce the amount of power consumed in its production) for solar cells in the 3-5 year range, assuming peak power production which everyone knows isn't realistic. It is questionable whether PV solar power is even capable of replacing its own consumption, which is tantamount to throwing our hard work and hard earned money into a rocket and shooting it into space, to be smashed and burned in the cradle of entropy.
    Oh, and nice use of scientific magic (leaving out the facts/units to make your point seem more shocking, must have taken some direction from the climate change council) in stating "nuclear plants create radioactive waste in direct proportion to the energy produced". Of course the units of that particular equation are likely ounces per GigaWattHour, but nevermind. As long as the multiplier is large enough, the universe is in proportion to the weight of air in each of your breaths.

  • February 18, 2008

    7:23 a.m.

    Suggest removal

    VVVV writes:

    By the way, "entropy compensating" is bordering on outright falsehood, implying that somehow entropy can be turned down or even go the other way. This is disgraceful for a physics teacher. If renewables are so unavoidable, how about we let the market play out and they will prove their worth on an equal footing. Granted, I believe ethanol should have to do the same.

  • February 18, 2008

    10:12 a.m.

    Suggest removal

    Coco writes:

    Oh, my goodness. I've taught chemistry for 23 years and I always encounter folks like you, CL, et al. You pull out something from your middle school physical science text and think you've got all the answers. Dr. Bradely has a PhD in physics! Clearly what is covered in his letter is a succinct summary of a very complex system. When you get your advanced degrees in a physical science, then you can come back with a "relatively" intelligent remark. (Uh, oh, here they come with their lists of their advanced (made-up/ internet) degrees.)

    Before you rip me to shreds with stuff you looked up on the internet or heard Rush, or Mike say, look up some terms: matter spread, energy spread, exothermic, endothermic, enthalpy, entropy, Hess's law, Gibb's free energy diagram, sequestered carbon. . . .