Blinded by Progress
By Dave Latoche
With the ongoing fixation on carbon dioxide being the cause of “possible global warming,” I think we may be “fiddling while Rome burns.” With all the talk of the dangerous build-up of CO2, nary a word is mentioned of “waste heat,” of which every BTU of energy that we consume becomes “waste heat.” The laws of thermodynamics say this is so, and cannot be rescinded. Eons ago, individual people discovered that fire was a source of power. The idea spread and eventually made modern civilization possible. In the more modern era, engineering as a discipline, already rooted, now flourished. But at some point, an assumption for the sake of convenience was made. This assumption was that the surroundings are an infinite heat sink. Bear in mind that for the purpose of designing, for example internal combustion engines, etc, then this assumption is perfectly valid, for a designer generally focuses only on the design of his or her particular project and not on any larger implication. The problem is that this early assumption, meant only for the purpose of designing various things that used energy, gradually grew into an assertation of fact about the larger world; a completely unquestionable tenant of modern engineering in relationship to the environment of the globe. Maybe it’s time to re-examine that assumption.
While the effect of large cities on the local climate is recognized, perhaps we should take a more inclusive all encompassing view of our energy usage. We are using gargantuan quantities of energy from oil, coal, gas, etc. all around the globe. A great deal of these fossil fuels is converted to electricity at huge generating plants. During the conversion stage, much of the heat energy is given off to the atmosphere either through the chimney along with the flue gases, or dissipated through cooling towers, or discharged as warm water into a nearby river. Also combustion releases water vapor, which has a greater “green house effect than carbon dioxide.” Further more, once the energy of combustion is converted to electricity, the trail of waste heat continues. As the electricity is transmitted, heat is given off along the transmission lines and at the transformers. When the electricity is converted into light energy or mechanical motion, most of this energy ultimately ends up as heat again. Although most of this heat loss is not noticeable, it is measurable, and added up. The amounts are very great indeed.
We have many millions of internal combustion driven vehicles around the world. They convert the energy given off by combustion into motion. Again, the total amounts of energy that these vehicles consume and give off as waste heat is staggering. These automobiles, trucks, trains, boats, and airplanes lose a good portion of the heat of combustion through their exhaust and then more again through their cooling systems. All engines need a cooling system: with land vehicles the cooling system gives off its heat to the air. With ships, that cooling system gives off its heat to the rivers and oceans upon which they travel. The amount of heat given off into the rivers and oceans by the giant barges, tankers, and military vessels would be considerable. Also energy of motion is lost through friction with the medium through which they travel, whether that is the tires against the road, the air against the surface of the vehicle, or the water against the surface of the boat.
The fact that heat losses from the transmission of electricity and from vehicles is spread out over a wider area and not usually noticeable or easily measurable, does not make it insignificant. In total, the amounts are very large.
All of our dwelling places, large and small, over large portions of the globe, must be heated. If they are heated with fossil fuels, a portion of this heat goes into the atmosphere through the flue gases and the rest is merely delayed in the dwelling place. All this heat is dissipated to the surrounds through the walls, sooner or later, depending upon how well the place is insulated. If the dwelling is heated by electric resistance heat, the trail of heat lose begins at the generating plant and ends at the dwelling, with every BTU released into our environment.
All of societies mechanized activities including travel and industrial processes give off a certain amount of heat. The sum of all this waste heat forms a more or less constant baseline which is added to the Earth’s solar gain, 24 hours a day, 7 days a week. The magnitude of this baseline while large is growing ever larger.
Besides the magnitude of the heat that we are releasing into the biosphere perhaps there are also synergistic effects that come into play. Synergy can be defined as the interaction of two or more agents or forces so that their combined effect is greater than the sum of their individual effects. For example we will commonly go into an area, raze the trees and bulldoze the greenery, which both had previously had a cooling effect, and then build blacktopped parking lots and roads and erect black-roofed buildings. Often we will do this in parts of the world that are already very hot. In addition we will then add internal combustion engines, fossil fueled power plants, etc. to the locale. It might be reasonable to assume that there would be a net warming effect from those changes. Perhaps this warming effect extends further and perhaps is greater than the sum of its components.
Not only do we add heat to the environment at all times due to travel, trade, and industry but we also exert feedback into the natural environment due to residential and business heating and cooling needs. During the “heating season” man’s consumption of all types of fuel and electricity increases in direct proportion to how cold the outside environment is. By necessity, the colder the weather, the more energy we infuse into our homes and businesses, and of course this all leaks “out.” Now an ever-increasing amount of electricity consumption is used for cooling both for air conditioning homes and businesses and to run the ever-increasing number of food and beverage coolers. These cooling processes consume more energy in direct proportion to how high the outside temperature is. By increasing the generation of electricity we also infuse even more energy into the surroundings as it gets hotter outside. Just to repeat, we are adding a positive baseline of heat to the environment at all times, which alone would tend to raise peak temperatures and also raise low temperatures from the previous average. Then again we are adding feedback to the environment for the colder it gets, the more heat we release and the hotter it gets the more heat we release. This process would also tend to raise peak temperatures and low temperatures as well.
And what effect do the vast military, commercial, and pleasure craft navies of the worlds nations have on the ocean temperature or on just the surface temperature. It is said that various types of ships have their own unique heat signatures, making them readily identifiable by infrared imaging via satellite. For all the waste heat of the engines of gigantic battleships, cargo ships, tankers, and cruise liners is released into the surface of the ocean as they travel. Furthermore, ships that require cooling of product or people would use cooling methods that would result in the release of even more heat into the oceans. Although the oceans are vast, is it not possible that there is some effect, especially where marine traffic is large and/or where surface temperatures are already warm. Warm water tends to stay on the surface, and stay warm especially during times of little wave action and when days and nights are warm. Is it not possible that synergistic effects would be seen on sections of the world’s oceans?
There is theory of chaotic behavior, which states that the behavior of very complex systems can be perturbed by relatively small changes from within or outside the system. For instance, supposedly the beat of a butterfly’s wings in South Africa could trigger a blizzard in the Arctic. The point is that chaotic behavior is unpredictable. The weather is widely regarded as a chaotic system and we are making more than small changes to the “outside” world.
Some mental images maybe be appropriate to try to comprehend the scale of the changes that mankind is causing. If the early image of mankind was of scattered bands of people crouched around camp fires, then we have reached a point where a far different scene can be imagined.
If we were naturally endowed with sensitive infrared vision the modern world would be an eye-opening experience. It may help to conceptualize this by imagining this in our local area, perhaps as we drive to work. Picture every source of energy consumption as an open fire. In regards to the laws of thermodynamics it matters not that the energy conversion is contained within a car engine, a home heating system, or an electrical generating plant. It matters not that the conversion from potential energy to kinetic takes place in an open fire or within any of our numerous power devices. All of that heat is sooner or later released to the great outdoors.
Now on this drive to work we would see vehicles of every size, each represented by a fire within, some smaller and some truly large. A busy highway would appear as a continuous stream of fire, for we are burning streams and rivers of oil. A power plant would appear as a gigantic bonfire. Buildings of every sort would glow with fires within.
Meanwhile the scientific debate appears to regard all of this heat as negligible. Maybe it is and maybe it isn’t but it does seem worth mentioning when the numbers have become so large! Figures vary but one source puts the conservative total yearly solar input at 7.577x1020 BTUs or 757,000 quads1. Another source puts man’s total energy consumption for 2004 at 412 quads2. Thus man’s total yearly energy consumption seems to be 1/1000 of the total yearly solar gain. We find in the on line encyclopedia, Wikipedia3, that the total solar energy reaching Earth is 1.74x1017 watts, and that the tidal energy amounts to 3x1012 watts. The same source puts mankind’s waste heat from fossil fuel consumption at 1.3x1012 watts. Thus it seems that mankind’s waste heat from fossil fuel consumption alone represents 4 times the power of the world’s tides.
To me these are huge numbers and I find it incredible that mankind’s consumption of energy represents more power than the power of the tides (if the figures are truly accurate). Then again, perhaps it is the where and the when of our heat releases, synergistic effects and feedback that are bigger factors than simply the magnitude of our waste heat. I am not a climatologist but have some science background and read a lot. I also work a job in which I directly experience the heat energy that we are releasing into the environment. If this waste heat has become a factor in our weather, it doesn’t help to ignore the issue.
1. Solar Radiation Budget. Bonnet, Bernard Yves, http://www.geocities.com/RainForest/3621/SOLAR.HTM
2. International Energy Outlook 2005 – Highlights. U.S. Government, http://www.eia.doe.gov/oiaf/ieo/
3. Earth’s Energy Budget. Wikipedia, http://en.wikipedia.org/wiki/Earth's_energy_budget