Closing The Cycle: Energy and Climate Change
Manuel Garcia, Jr.
7 December 2011
Open Cycle Industrialization
- Defining Sciences of Heat in Continuous Matter
- Heat Engines, Thermodynamic Cycles and the 1st Law
- The 2nd Law, and the Heat Gradient Across a Cycle
- Waste Heat, and the Cold Point Infinite Heat Sink
- Disorganization, Irreversibility, Entropy and the 2nd Law
Chemical Thermodynamics of the Biosphere
- The Civilization-Producing Heat Engine
- Complete Heat Engine Cycle of the Biosphere
- Industrial Heat Engine Cycle
The Global Heat Balance
- Incident Solar Energy
- Conversion of Light to Heat by the Earth
- Radiated Heat Energy
- Converting Absorbed Radiation into Atmospheric Heat
- Biosphere and the Surface Temperature of the Earth
- General Equation for the Global Heat Balance
- Sources of IR Absorbing Gases in the Atmosphere
- IR Absorption Coefficient Depends on Temperature
- Defining Global Warming
Closing The Cycle: Energy and Climate Change
(Toward Naturally Stable Energy Cycles For Enduring Societies)
Global Warming is a fact. What are we going to do about it?
This article is intended to prompt responses to that question.
The plan of this article is to proceed through a sequence of topics:
- global warming is the environmental response to open cycle industrialization
- a combination of heat flow physics and chemistry produces global warming
- the politics of deciding on forms of energy between options with uncertain futures
- international energy-climate conflicts reflect disparities in levels of development.
Global closed cycle industrialization will require equalizing levels of development:
- assistance from “high” to “low,” of value comparable to reparations for colonialism
- move from “open cycle” politics to morally “closed cycle,” domestic & international
- global warming can be seen metaphorically as the entropy of economic warfare
- the inertia of self-interest will resist halting humans’ stimulation of global warming.
Open Cycle Industrialization
Industrialization concentrates energy into mechanized work to build up civilization.
Industrialization is organized as capitalism predominantly powered by fossil fuels.
Capitalism is open loop economics in either of two forms:
- “the free market,” financial speculation by massed private capital; or
- “communism,” state-directed centrally-planned economic investment.
Open loop economics is Resource, Labor, Social and Environmental exploitation:
Resource: the extraction or seizure of assets from the environment and society:
- mining, forestry, farming, herding, land seizures, water, air, public subsidies.
Labor: purchase labor at minimum cost by exploiting human survival needs:
- fragment work into small repetitive tasks, for efficiency with low-cost low-skill labor
Social: dump wastes on and shift liabilities to society, “socialize costs” as in:
- dumping wastes, instead of recycling the usable, and reprocessing the unusable
- avoiding taxes, even through buying political influence to weaken democracy
- evading regulations, increasing risks to the public, for privatized gains
- shielding owners from responsibility by legalism, corporate personhood (or state)
- bailing out corporate bankruptcies with public funds (or by nationalization).
Environmental: expect the environment to complete the industrial cycle, to:
- endlessly supply “natural resources”
- steadily maintain society that supplies labor & profits, absorbs production & costs
- have infinite capacity to disappear wastes, both material and heat; to be a sink.
The open cycle pretends to be closed by depending on the environmental sink as:
Global warming disproves the infinite sink assumption about the environment.
The naturally stable alternative is closed cycle industrialization:
- closed loop economics
- mutually supportive resource, labor, social and environmental interactions
- full cycle responsibility coincident with cycle ownership.
“Politics is a process by which groups of people make collective decisions.”
Energy and Climate Politics
is how we make collective decisions about closed cycle industrialization.
Defining Sciences of Heat In Continuous Matter
Thermodynamics is the science of:
heat causing, and being released by, the mechanics of chemically inert matter.
Chemical thermodynamics is the science of:
heat causing, and being released by, the mechanics of chemically reactive matter.
Thermodynamics: a full tea kettle heated so boiling water spills out, and steam flies.
Chemical thermodynamics: rocket fuel and oxidizer reacting to form a jet exhaust.
Heat Engines, Thermodynamic Cycles and the 1st Law
Heat engines produce mechanical work from absorbed heat.
A heat engine has a working fluid (gas, liquid) that makes a thermodynamic cycle:
- fluid temperate and pressure increase by absorbing heat from a heat source, it
- returns heat by doing work, exerting pressure against a movable surface (motion),
- finally, it rejects unused heat to the environment (cooling) to begin a new cycle.
Cyclic change in the internal energy of the working fluid equals the difference of:
- the heat absorbed, and
- the work done plus heat lost as waste.
- This is the 1st Law of Thermodynamics.
The 2nd Law, and the Heat Gradient Across a Cycle
Spontaneously, heat flows only:
- from higher temperature zones
- to lower temperature zones.
- This is an observable effect of the 2nd Law of Thermodynamics.
In a thermodynamic cycle typical of industrial heat engines, the working fluid is:
- heated and compressed from an initial low temperature, low pressure state, then
- expanded as it does work, cooling to that low temperature and pressure state;
- work done (+heat lost) equals the heat flow from cycle’s high to low temperatures.
Heat engines operate in either a closed or open cycle:
- closed cycle: the same mass of fluid repeats the same thermodynamic cycle,
- open cycle: a fresh mass of fluid is used for each cycle, then expelled.
Engine efficiency and output increase with a larger cycle temperature difference:
- to release more heat, burn fuels with higher chemical potential energy,
- cool the low temperature site of the thermodynamic cycle.
Waste Heat, and the Cold Point Infinite Heat Sink
Not all the heat released from the fuel enters the working fluid:
- engine efficiency is always less than 100%, often much less,
- some of the heating is lost into the mass of the engine, and conducted away,
- some of the heating is lost with the expulsion of hot exhausts from open cycles,
- some of the heating is lost into the mass of passing external coolant streams.
Where does this waste heat “conducted away,” “exhausted,” and “cooled” go?
- to an infinite heat bath, or heat sink,
- also known as an infinite heat reservoir at constant temperature.
An infinite heat bath can:
- absorb any amount of heat from a hotter body, without a rise in temperature,
- release any amount of heat to a colder body, without a drop in temperature.
The environment is assumed to be the infinite heat sink for practical heat engines.
Global warming seems to show:
the environment is a finite heat bath to industrialization’s accumulated waste heat:
- but waste chemicals are crucially involved to produce observed global warming
- so, will show later that the environment is a finite chemical thermodynamic sink.
Disorganization, Irreversibility, Entropy and the 2nd Law
Consider a thermodynamic system with three elements:
- hot source at temperature T-hot, produced by combustion (internal or external),
- heat engine,
- infinite heat bath defining the cold point, T-cold, of the thermodynamic cycle.
In its initial state, this system is highly organized:
- only a few chemical forms of matter (fuel, air, working fluid if different), and
- potential energy is well-confined in the form of chemical bonds of fuel molecules.
System organization degrades through the thermodynamic cycle (1-4):
1. At the beginning of one cycle:
- a charge of fuel and oxidizer is injected into the engine
- the working fluid is in a cool relaxed state
- none of the chemical potential energy of the charge has been used or lost.
2. During the cycle’s transition from heat absorption to working:
- chemistry produces heat by breaking up fuel molecules into numerous species
- the working fluid is hot, compressed, in motion and agitated
- waste heat has been released to the environment.
3. At the end of performing work:
- combustion has produced many species with less total chemical potential energy
- the working fluid is too cool and expanded to produce more work in this engine
- any remaining heat in the engine walls and working fluid is lost as waste.
4. The rejection of waste heat and mass to the cold infinite sink resets the cycle:
- closed: the working fluid is cooled and expanded to initial conditions,
- open: the working fluid of warm combustion products exits, replaced by cool air.
This cycle is not perfectly reversible (5-8):
5. It is not possible to recreate the initial degree of organization of:
- chemical energy stored in a well-defined single molecular species of fuel mass,
- a charge of cool air,
- working fluid in a cool relaxed state…
6. … By “starting” with:
- the end products of combustion drawn back from the cold infinite reservoir
- through the engine operating in reverse
- by applying an equivalent amount of work to it, as was produced earlier,
- (remember the losses to waste heat)…
7. … And compressing the working fluid:
- so as to convert the work being applied into heat,
- which the working fluid is to release to the hot source point
- by a sudden and spontaneous cooling, so it returns to its initial cool relaxed state.
8. Some reversibility may be possible (work into heat), but never completely:
- some of the “organization” or “information” of the initial state is irretrievably lost
- we can never recreate the initial state by a reverse cycle given the same energy
- to reconstitute the initial state from the final products requires more energy
- a reversible cycle is one with no heat lost to waste (or work lost to friction).
Entropy is the thermodynamic property that quantifies system disorganization:
- the more disorganized the state of a system, the higher its entropy.
The increase of entropy over a cycle quantifies its degree of irreversibility:
- there is zero net entropy change over a reversible cycle.
For every thermodynamic cycle of any thermodynamic system:
- the entropy always increases,
- or at a minimum remains unchanged; it never decreases (macroscopically).
- this is the 2nd Law of Thermodynamics.
One lesson in irreversibility, preserved as the memory of a famous “top egg,” is:
Humpty Dumpty sat on a wall,
Humpty Dumpty had a great fall.
All the king’s horses and all the king’s men
Couldn’t put Humpty together again.
Chemical Thermodynamics of the Biosphere
The Civilization-Producing Heat Engine
Humanity is a Heat Engine that Digests Energy to Produce Civilization.
Parallel statements of the civilization-producing heat engine (1-6):
Natural energy is tapped to flow down the gradient of human energy use (1), degrading from its pristine state of sharply defined natural organization (2), as (primarily) fossilized storage and photosynthetic cycling (3), as it cascades through our industrial forms (4), to wash out into a stagnant and disorganized global heat sink (5). It is left to Nature to be both an infinite waste sink and infinite fuel/heat source, to absorb the waste output, and reset the cycle to its initial conditions (6).
Natural energy is tapped to flow down the gradient of human energy use (1), entropy increasing (2), from a “hot” reservoir and/or an initial state of concentrated energy/information (3), through humanity’s motor (4), exhausting to global warming, the “cold” reservoir, high entropy end of the cycle (5). It is left to Nature to be both an infinite waste sink and infinite fuel/heat source, to absorb the waste output, and reset the cycle to its initial conditions (6).
(1) Natural energy is tapped to flow down the gradient of human energy use,
- degrading from its pristine state of sharply defined natural organization
- entropy increasing,
- as (primarily) fossilized storage and photosynthetic cycling
- from a “hot” reservoir and/or an initial state of concentrated energy/information,
- as it cascades through our industrial forms
- through humanity’s motor,
- to wash out into a stagnant and disorganized global heat sink.
- exhausting to global warming, the “cold” reservoir, high entropy end of the cycle.
(6) It is left to Nature to be both an infinite waste sink and infinite fuel/heat source,
to absorb the waste output, and reset the cycle to its initial conditions.
Complete Heat Engine Cycle of the Biosphere
The Life Cycle has 2 complementary processes that are the reverse of each other:
- aerobic respiration
Photosynthesis (simplified reaction):
6CO2 + 6H2O + light (energy) -> C6H12O6 (sugar) + 6O2
carbon dioxide + water + solar energy -> sugar (food) + oxygen
Aerobic respiration (simplified reaction):
C6H12O6 (aqueous) + 6O2 (gas) -> 6CO2 (gas) + 6H2O (liquid) + energy
sugar (food) + oxygen (breath) -> carbon dioxide + water + metabolic energy
Autotrophs (self-feeding organisms)
- like plants, algae and many bacteria
- carry out photosynthesis
- producing organic compounds (food) from inorganic matter (CO2, H2O)
- by absorbing sunlight; or
- carry out geochemical synthesis
- producing organic compounds (food) from inorganic hydrogen compounds (H2S)
- by absorbing heat and, e.g., hydrogen sulfide from vents submerged in darkness.
Heterotrophs (organisms that feed on others)
- like animals, fungi and many bacteria
- carry out aerobic respiration
- releasing food energy and then storing it as adenosine triphosphate, ATP,
- while also producing organic and inorganic (CO2, H2O) wastes;
- ATP is stored metabolic energy, which can drive cellular processes like:
– biosynthesis (the formation of more complex molecules, like enzymes),
– locomotion (the movement of structures, like proteins, within cells), and
– transportation of molecules across cell membranes.
The Stable Energy Cycle of the Biosphere (the Life Cycle):
Autotrophs process inorganic matter and heterotroph waste into food and O2,
- food is solar energy captured in organic chemicals (carbon-hydrogen bonds).
Heterotrophs consume food and O2 to produce metabolic energy stored as ATP,
- waste products are CO2, H2O and organic matter.
Industrial Heat Engine Cycle
Industrial use of heat is loosely analogous to aerobic respiration by heterotrophs.
Combustion of methane (CH4) is shown here as a representative heat source:
CH4 + 2O2 + ignition -> CO2 + 2H2O + heat
- actually, create many C, H and N oxides, and nitric acid, by burning CH4 in air,
- we depend on nature (autotrophs) to reprocess industrial CO2, and supply fuel,
- there is no re-organizing/re-concentrating of waste heat: entropy only increases.
The Global Heat Balance
Incident Solar Energy
Insolation: solar constant (source)
Milankovitch Cycles (distance and local incident angle):
Describe the collective effects of changes in Earth’s movements on climate.
Gravitational interactions in the Solar System cause long-term periodic changes of:
the distance and orientation of the Earth with respect to the Sun:
Orbital Shape (eccentricity)
- change in the elliptic shape (variation from circular) of Earth’s orbit
- with an approximately 100,000 year period (cycle).
Axial tilt (obliquity)
- a 2.4 degree shift of angle between Earth’s axis and orbital plane, and a return,
- with a 41,000 year period.
- trend in the direction of the axis of rotation relative to fixed stars,
- with a 26,000 year period.
Transmission (filtration of insolation by atmosphere):
- atmosphere is transparent to visible light (radiation)
- absorption of ultra-violet (UV) in the high altitude ozone layer
Reflection (Earth’s albedo, its net reflection coefficient for visible light):
- ice sheets and snow (extent of the area has long term stability; Milankovitch cycle)
- clouds (extent of the area is highly variable over very short time; unpredictable)
- oceans and land absorb visible light (reflectivity is low)
The Conversion of Light to Heat by the Earth
- Atoms and molecules absorb incident light, and redistribute it in matter as heat.
- Matter holds heat as the agitation, rotation and vibration of molecules (& atoms).
- Motions of positive and negative parts of molecules launch electric waves.
- Wavelengths are set by molecule sizes and deflections: infrared radiation (IR).
- IR radiation is that portion of the electromagnetic spectrum we sense as heat.
- IR radiation is emitted by the surface of the Earth (land, oceans and organisms).
- Typical frequency of thermal radiation increases with the emitter temperature.
- Quantity of thermal (Black Body) emission increases with emitter temperature.
Radiated Heat Energy
Transmission through the atmosphere:
- gases made up of symmetric molecules (N2, O2) are transparent to IR radiation
- gases made up of atoms (Helium, Neon, Argon) are transparent to IR radiation
Absorption by the atmosphere (reflection is negligible):
- gases of asymmetric molecules (have positive and negative ends) absorb IR
- IR absorbing gases also emit thermal radiation characteristic of their temperature
- IR absorbing gases are: H2O, CO2, NOx (pollution) and volatile organic vapors
- trapped IR is continuously absorbed and radiated within the mass of atmosphere
- the greater the mass of IR absorbing gases, the greater the capacity to store heat.
Converting Absorbed Radiation into Atmospheric Heat
Kinetic theory of gases:
- Gases are mainly empty space with a huge number of small particles in motion.
- These particles are the atoms & molecules of gaseous elements & compounds.
- The faster a particle’s speed, the higher its kinetic energy, its energy of motion.
- The sum total of particle kinetic energy in a gas volume is its heat content.
- Temperature is defined as the ratio: [heat content in volume]/[mass in the volume].
- Temperature is a measure of the average kinetic energy of the particles.
- Moving atoms and molecules in a gas collide frequently, randomizing directions.
- Particles transfer kinetic energy by collision, from energetic to lethargic particles.
- Collision frequency is high, so most particles have comparable kinetic energy.
- Also, the high collision frequency diffuses a “hot spot” into a larger volume.
The positive & negative poles of asymmetric molecules make them IR antennas.
Received (absorbed) IR radiation can be stored:
- internally: bending and vibration of the atom-to-atom chemical bonds
- internally: rotations of the entire molecule (rolling, spinning, flipping)
- kinetically: linear motion through the space between particle collisions.
Molecules can transfer some of their internally stored energy during collisions:
- internally stored IR energy can be transferred into kinetic energy by collisions
- one species’ internal energy can be spread kinetically to all other gas species
- collisions distribute IR radiation absorbed by one species into uniform gas heat.
Adding vapors to the atmosphere that increase IR absorption will cause it to heat.
The Biosphere and the Surface Temperature of the Earth
Biosphere is from the top of the stratosphere (50 km above sea level) down to:
- about 5 km below the surface of the land (at 124°C, too hot for bacteria), and
- about 11 km below the surface of the oceans (just below the deepest ocean floor).
The heat content of this outer region of the Earth is affected by Milankovitch cycles.
Earth’s temperature increases with depth (land) at an average rate of 22.1°C/km
- but the flow of interior heat out through the Earth’s surface is negligible.
Global Warming refers to the average temperature of the atmosphere and oceans:
- assumed here: a layer of the biosphere bracketing “the elevation at sea level”
- from 20 km up, the top of the troposphere, including nearly all atmospheric mass
- to 10 meters below ground, which day/night and seasonally temperature cycles,
- and also the fluid mass of the oceans, whose currents redistribute heat energy;
- this layer’s temperature is set by the balance of solar heating and radiant cooling.
Earth’s average surface temperature during 1901-2000 was 13.9°C = 57°F.
T = average surface temperature of the Earth
H = the heat content in the surface layer (the essential layer of the biosphere)
C = the heat capacity of the mass of the surface layer (average material property)
ΔH = a change in the heat content of the biosphere layer (a gain or loss)
The relation of heat content to temperature is:
H = C•T
When a quantity of heat ΔH is added to the surface layer then:
H(new) = H(old) + ΔH
T(new) = T(old) + (ΔH)/C
When, in the above:
ΔH is positive, heat was added, and the new temperature is higher,
ΔH is negative, heat was lost, and the new temperature is lower.
General Equation for the Global Heat Balance
Global warming is determined by the balance of solar heating and radiant cooling.
The general equation for this global heat balance is:
ΔH = S•(1-A) – Q•(1-F)
ΔH = change in the heat content of the biosphere/surface layer
S = incident solar energy (light reaching the top of the atmosphere)
A = albedo: reflection coefficient of the Earth (0 < A < 1)
Q = radiated heat energy (infrared emitted by Earth’s surface)
F = IR absorption coefficient of the atmosphere (0 < F < 1).
A (albedo), F (IR absorption), Q (thermal emission) depend on Earth’s temperature.
Change in Biosphere Heat Content =
(Incident Solar Energy) • (1-Albedo) +
- (Radiated Heat Energy) • (1 – IR absorption coefficient of the atmosphere)
Heat flow from Earth’s interior to the surface is negligible, equal to about S/10,000.
During a period of stable climate:
ΔH = 0, incoming (light energy) and outgoing (heat energy) flows balance.
Q•(1-F) = S•(1-A), thermal emission into space = solar irradiation at Earth’s surface.
For an interval during which climate changes:
ΔH ≠ 0, incoming (light energy) and outgoing (heat energy) flows are not balanced.
Q•(1-F) > S•(1-A), thermal flux to space > solar irradiation if the Earth is cooling
Q•(1-F) < S•(1-A), thermal flux to space < solar irradiation if the Earth is heating.
Sources of IR absorbing gases in the atmosphere
Terrestrial emission of organic plumes from:
- volcanic and geothermal venting
- methane outgassing caused by rising temperature (tundras and oceans)
Industrial emission of organic plumes from:
- chemical, mining and manufacturing facilities
- concentrations of agricultural and livestock activities
Air pollution from combustion-derived heat energy for industrialized civilization.
IR absorption coefficient depends on temperature
Evaporation of liquid H2O, and organic vapor plumes increase with temperature:
- cloud dynamics and distribution is the most contentious aspect of climate models
- terrestrial outgassing of IR absorbing gases increases with Earth’s temperature.
Hotter wetter eras may also be cloudier with both higher albedo and IR retention,
- compensating effects, which slow rate of heating.
Colder drier, large ice sheet eras may have higher albedo and lower IR retention,
- mutually amplifying effects, which accelerate rate of cooling.
Defining Global Warming
“The environment” is the 20-31 km thick surface-of-the-Earth layer of the biosphere.
Global warming shows that:
- the environment is not an infinite chemical thermodynamic sink,
- it cannot endlessly absorb waste heat and IR absorbing chemicals isothermally.
Global warming is:
- the increase of entropy in the environment.
- the degradation of organization of the environment.
The above is the outline of the physical science half of my never-to-be-finished book on the politics of climate change. Some of the energy-use policies and technologies that could be implemented in response to climate change were described in my article
The Economic Function Of Energy
27 February 2012
“The Economic Function Of Energy” covers the topics listed as the third and fourth lines itemized in the preface (at the start).
The last four lines itemized in the preface are discussed in a haphazard fashion in several of my articles posted on the Internet (see http://manuelgarciajr.com or http://manuelgarciajr.wordpress.com), most recently in “AGW And Malthusian End Times.”
I think that today everybody understands that Anthropogenic Global Warming will not be addressed, nor resource and energy conservation practiced, until capitalism is rejected globally, and that humanity will never reject fossil-fueled capitalism.