What portion of global warming is due to waste thermal energy (entropy) produced by humans.?

Question

I do not mean energy trapped by greenhouse gases. Humans are continually increasing their energy consumption and since no process is 100% efficient, much energy is lost as heat.

Answer 1

We consume about 470x10e18 joules per year, as of 2004. The earth has a surface area of  about 510 million km2,  and a year is 3153600 seconds. Crunch the math and you get about .03 watts per square meter for all human energy usage. The IPCC estimate for the heat forcing from our greenhouse gas production is about 3 watts per square meter, so our direct contribution to the heat from all human activity is around 1% of that from our greenhouse effect contribution .

Added - I was offline when Bob answered, so used different sources and math. It was nice to see that our answers substantially agree.

Answer 2

Didn't save all the links, but you can verify this.

Total area of the Earth is about 5X10**14 meter squared.

Global warming is about 2 watts per meter squared or about 10**15 watts.

Total energy production is about 15 terawatts or 15X10**12 watts.  About 1.5% of the warming, if you assume 0% efficiency or that it all gets lost as heat eventually.

Looks like we're having to leverage the sun with CO2 to make it happen.

That one was fun.

Answer 3

I am a Thermodynamic and Environmental Engineer. I am attaching an essay I wrote maybe 10 years ago - but it still holds true - moreso now than ever.

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Effects of Entropy

It was during the 70’s when the Energy Act (1976) arose that my degrees, Thermodynamic Engineering and Environmental Engineering, were only then being taken seriously. There is a genuine interest these days in the mind boggling numbers associated with exponential growth, I hope you find this even more mind boggling. The energy used to put a deck of cards in order far exceeds knocking them out of order is nothing compared what is happening as we go through the J-curve of the effects of Entropy (a good indicator of Entropy is money, as the world economy inflates, so goes money – and Entropy). (In my views) the Laws of Thermodynamics reign supreme over the Universe.  We are already using 20% more energy than the Earth can provide. If all greenhouse causing agents are stopped being used today, it would take at least 100 years to get the global warming momentum to settle. While the masses wait for the Engineers and Scientists to save the world with a “by the time I get cancer there will be a cure for it” attitude, this is an example of what is;

Nobel chemist Frederick Soddy pointed out over 70 years ago: “Debts are subject to the laws of mathematics rather than physics. Unlike wealth, which is subject to the laws of thermodynamics, debts do not rot away with old age and are not consumed in the process of living. On the contrary, they grow at so much per cent per annum, by the well known mathematical laws of simple and compound interest”1

Economist Herman Daly explains the inevitable consequences that result when society pits the mathematical notions of compound interest against the physical reality of thermodynamics. He says that while debt can grow at compound interest forever, real physical wealth cannot continue to grow at the same speed “because its physical dimension is subject to the destructive forces of entropy.”2 He concludes: “Since wealth cannot continually grow as fast as debt, the one to one relation between the two will at some point in time be broken- i.e. there must be some repudiation or cancellation of debt. The positive feedback of compound interest must be offset by counter acting forces of debt repudiation, such as inflation, bankruptcy, or confiscatory taxation, all of which breed violence.”3

At every step in the entire production and exchange process, work is done; namely, energy is expended by both humans and machines. Part of that energy is absorbed into the product and part is wasted. This means that the more stages in the economic process, the more energy is lost. The same principle is at work in the production process as in the simple food chain. In highly industrial societies the stages of the economic process continue to proliferate, meaning more and more energy is dissipated all along the line; and the resultant disorders create even greater long-range problems for society.

Take, for example, your morning English muffin. The very process of modern petrochemical agriculture used to grow the wheat is extremely energy inefficient. But once grown and harvested, the folly is compounded many times thanks to our national mania for processed food. Here are just some of the energy steps that go into making your English muffin. (1) The wheat is taken by a fossil-fuel-driven truck made of nonrenewable resources to (2) a large, centralized bakery housing numerous machines that very inefficiently refine, enrich, bake, and package English muffins. At the bakery, the wheat is (3) refined and often (4) bleached. These processes make for nice white bread, but rob the wheat of vital nutrients, so (5) the flour is then enriched with niacin, iron, thiamine, and riboflavin. Next, to insure that the English muffins will be able to withstand long truck journeys to stores where they will be kept on shelves for many days, or even weeks, preservative (6) calcium propionate is added, along with (7) dough conditioners such as calcium sulfate, monocalcium phosphate, ammonium sulfate, fungal enzyme, potassium bromate, and potassium iodate. Then the bread is (8) baked and placed in (9) a cardboard box which has been (10) printed in several colors to catch your eye on the shelf.

The box and muffins are placed within (11) a plastic bag (made of petrochemicals), which is then sealed with (12) a plastic tie (made of more petrochemicals). The packages of English muffins are then loaded into (13) a truck which hauls them to the (14) air-conditioned, florescent-lit, Muzak filled grocery store. Finally, you (15) drive two tons of automobile to the store and back and then (16) pop the muffins in the toaster. Eventually, you will throw away the cardboard and plastic packaging, which will then have to be disposed of as (17) solid waste. All of this for just 130 calories per serving of muffin.

Not only have tens of thousands of energy calories gone into the entire process, but medical evidence suggest that both the additives and the lack of fiber in refined breads may pose a serious hazard to your health. In the end, the energy that was added to the muffins at each step of the process was insignificant compared with the energy that was dissipated at each step of the process.

Of the total amount of energy used in the food system, less than 20 percent actually goes into the growing of food. The other 80 percent is consumed by the processing, packaging, distribution, and preparation of the foodstuff. Almost twice as much energy is used to process your English muffin (33 percent) as was used to grow the grain it was made from (18 percent).4

The food processing industry is now the fourth largest industrial energy user in the nation—after metals, chemicals, and oil. Some sources estimate that food processing currently consumes nearly 6 percent of the country’s energy budget. As far as the industry is concerned, apparently, the more the better. For example, between 1963 and 1971 the per capita food consumption in the United States increased by 2.3 percent. But the tonnage of packaging grew by 33.3 percent and the number of packages by 38.8 percent.5  I apologize for such old statistics, but that is when I first started to put information as this together, these are 30 year old figures, one can only imagine the statistics today.

Along with the growth in packaging has come a new industry; an entire army of “food technologists” now busy themselves making sure that our food supply is given just the right artificial color, scent, flavor, texture, and so on. Nothing can be left to chance. As one food technologist puts it, “It’s hard to compete with God, but we’re making headway.” Indeed they are. Some $500 million in synthetic chemicals is added to our food every year—2,500 additives. In 1979, each American consumed an average of nine pounds of additives, nearly double the amount in 1970. Four million pounds of dyes wind up in the food supply annually, a full sixteen times the amount used in 1940. Today, we eat more synthetic and artificial foods than the real thing.6

Convenience and processed foods, which are promoted as ways to liberate the individual from the “drudgery” of spending more time in the kitchen in food preparation, are in reality chaining humanity to the effects of ever greater entropy. The little time saved in the kitchen is more than outweighed by the amount of work time (human energy) given over to earning the money to pay for the increasing prices of the processed foods. Each step of the food processing takes energy, and as the energy flows through the food chain we witness a concentration of power in fewer and fewer food technology corporations, the decline in the healthfulness of the American diet, and the increased use of nonrenewable energy.

Food processing is representative of other major industries—such as petrochemicals, auto, truck and air transportation, and synthetic fibers—that grew up in the era of high energy flow. All appear to be generating greater value (more products, more “convenience”) while all the time they are actually squandering the precious energy resources of the planet. Again, the economic system fosters the illusion of creating a more ordered, more materially valuable world, because consideration is given primarily to value added or entropy decreases, but rarely ever to energy dissipation and entropy increases.

If the Entropy Law were fully acknowledged, society would have to face up to the notion that every time we use part of the stock of available matter and energy it means two things: first, that one way or another, the individual, the institutions, the community, or the society ends up paying more for the disorder created in making the product than the value derived from the use of the product; second, less energy is available to be used by other people and creatures sometime in the future. This reality flies in the face of the way we have viewed the world for the past several hundred years. The entire Enlightenment world view is inspired by the principles of Newtonian mechanics, Cartesian mathematics and Baconian scientific methodology. Capitalist and socialist systems attempt to organize the physical world on the basis of these basic conceptualizations. Central to all three ideas is the notion of absolute repeatability of observation (the scientific method) and the absolute reversibility of all processes (universal mathematics and mechanical processes). In the real world, however, nothing is observable in the same manner twice and no occurrence is reversible. The Entropy Law tells us that all physical reality unfolds in only one direction and that while there must be a -X for every +X in math, there is no such reversibility in the physical sojourn of the world around us. It is indeed bewildering that we have been attempting to organize the world for these past few centuries on the basis of mechanics, mathematics and the scientific method, when the real world simply does not conform to the central assumptions of reversibility and absolute repeatability. The reality is that when we leave this world, we leave it less well endowed as a result of our presence. When we glorify high energy production, then, what we are really promoting is an ever greater consumption of the finite store of resources of the planet. Seen in this way, the gross national product is more accurately the gross national cost, since every time resources are consumed they become unavailable for future use.7

Actually, the term consumption is a misnomer, for nothing is ever consumed. A thing is used, usually for a very short period of time, and then discarded. Any way you look at them, the statistics are mind-boggling. As a nation, we annually discard 11 million tons of iron and steel; 800,000 tons of aluminum; 400,000 tons of other metals; 13 million tons of glass; and 60 million tons of paper. Add to this 17 billion cans, 38 billion bottles and jars, 7.6 million discarded TV sets, and 7 million junked automobiles.8 The figures are no less awesome on the personal level. In 1974 the average American used 10 tons of mineral resources, including 1,340 pounds of metal and 18,900 pounds of nonmetallic minerals. In a lifetime, each American uses on an average approximately 700 tons of mineral resources, including nearly 50 tons of metals. If we add fossil fuels and wood, the per capita usage more than doubles to 1,400 tons. And this amount excludes water and food needs.9 Again, these are 1974 figures, you can imagine where these numbers are now.

It has been said before that the world could not possibly support another America. Looking at these figures, it becomes apparent that even one America is more than the world can afford now. Imagine if the entire world tried to produce and consume as Americans do. It has been estimated that a middle-class American lives a style of life that is equivalent to the work produced by 200 human slaves.10  Buckminister Fuller refers to us as possessing 200 “energy slaves” that run on nonrenewable resources. Another way of looking at it is in terms of number of calories needed to sustain life. An average human diet consists of 2,000 calories a day. Yet the amount of energy calories we individually consume every day – in our cars, our electricity, our processes foods, and so on – amounts to about 200,000 calories, or more than a hundred times the quantity we absolutely need.11 In terms of energy consumption, though Americans number only 298 million people, our energy needs are equivalent to that of over 23 billion individuals. How do we explain to future generations what we have done?

1. Herman Daly, “The Econimic Thought of Frederick Soddy” in History of Political Economy.

2. Ibid.

3. Ibid.

4. Dennis Hayes, Rays of Hope.

5. Ibid.

6. Orville Schell, “Inside the Food Technology Bazaar” in Mother Jones.

7. Jeremy Rifkin, Entropy, A New World View.

8. Hayes.

9. Jackson Davis, The Seventh Year.

10. Barbara Ward, The Home of Man.

11. G.Tyler Miller, Energetics, Kinetics and Life: An Ecological Approach.

Gary Ramos

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Answer 4

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