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能量是一种核算单位,可以用于衡量不同类型的力,包括重力、核能、太阳辐射和化学键。我们的星球以2.66 x 1040kg/m2/s动量在轨道上绕着太阳飞驰,以7.074 x 1033kg/m2/s角动量旋转。这些是自然赋予人类的免费礼物,人类无法控制,由它们给人类送来了四季、昼夜和宜居气候。太阳辐射是免费的,我们也不需要为重力付费。

但我们经常误算成本,水力发电是一个例子。湍流的水的力量是免费的蒸发作用和免费的地心引力下落作用的结果,人力成本是在开采矿山资源和在发电设施的设计和制造中产生的。人类提供的能量消耗在断裂烃类(主要是化石燃料)和碳水化合物(木材燃料和食物)中的碳氢键之中。

人类农耕和采矿所使用的能量,来自碳氢键断裂“释放”的热和力量,以满足人类需求(加热、生产和运输),结果是每个碳原子与空气中的一个或两个氧原子牢牢地结合到一起。一氧化碳中毒的人都希望氧原子与碳原子断裂分离,这样他们就能够再呼吸。然而,只有光合作用这样的奇迹才能实现,太阳释放的光子不断碰撞叶子,让二氧化碳分解,重新吸收为碳,释放氧。

分子寻求分母

令人难以捉摸的奇迹是,燃料一旦被使用就消失不见:油箱空荡荡;木料付之一炬;煤炭化为灰烬。自(史前石器时代)穴居人时期以来,直到1970 年之前,这些都是无所谓的事。现在,科学迫使我们注意到12克的碳燃烧产生44克的二氧化碳的事实。某些绿色主义者提议,通过立法,要求汽车司机将行驶产生的废气储存在后备箱,当排放物超重时,就驶入垃圾场银行缴纳罚款。要知道,一辆汽车每年产生7吨的废气。

更具挑战性的科学问题是,释放出的能量到底从何而来?化学工程师的回答总是老生常谈,事实证明那确实是相当肤浅的答案。在单个原子和分子水平上,一个分子的最简单燃料、天然气或甲烷(CH4)的燃烧,与两个氧原子结合,产生一个二氧化碳分子和两个水分子。燃料中碳和氢之间的库仑力与氧气分子中氧原子间的库仑力之和是27eV。燃烧后,新分子聚集了35eV的键能,释放了8eV用于加热、驱动汽车,或任意经济活动。1千克的燃料所释放的能量在14-46兆焦(megajoule,106焦耳)之间,木头、面包、天然气、煤、奶油、植物油、汽油依次增加。

Defining “energy”

The father of the scientific method, Francis Bacon, listed four sources of false thinking, of which the most insidious was misuse of language. He targeted “names of things which exist, but yet confused and ill-defined, and hastily and irregularly derived from realities”. One such abstract noun is “energy” – only coined 160 years ago by James Joule to express the relationship between a mechanical force (turning a wheel) and the heat unintentionally generated. It proved a useful concept but is now the source of endless confusion. Economists and politicians seem oblivious of the laws of physics: Energy cannot be created or destroyed, so it is wrong to say it is produced or consumed – it is transformed from useful to “unavailable” energy.

Energy is an accounting term that covers disparate types of forces, including gravity, nuclear, solar radiation and chemical bonding. If economists insist on accounting “global energy”, they would be exasperated when a scientist told them about the most important energy of the Earth. Our planet is hurtling through space on its orbit around the sun with a momentum of 2.66 x 1040kg/m2/s and its rotation had an angular momentum of 7.074 x 1033kg/m2/s. But these are free gifts of Nature humans have no control over that deliver seasons and day and night, and livable climates. Solar radiation is free and we do not have to pay for gravity either. Hydropower is an example where we miscalculate the costs. The force of rushing water is the result of free evaporation up and free gravity down, and human cost is in the work required to mine resources and design and manufacture components for the electricity generating facility. The energy that humans have to pay for is the breaking of bonds between carbon and hydrogen in hydrocarbons (mainly fossil fuels) and carbohydrates (wood fuels and foods).

Very few of the decision-makers and power-brokers at the Durban Conference will know or appreciate this (below) scientific fact: That when humans use energy that they have to work for, in farming and mining, there are carbon-hydrogen bonds broken to “release” heat and forces for human demand (heating, manufacture, transport) and the result is each carbon atom bonding very strongly with one or two oxygen atoms from the atmosphere. The C-H bond is held together with a matrix of coulombic forces that requires 4.2 eV to break but the carbon immediately bonds with O2 at 8.3 eV or worse, with one atom of oxygen at 11.1 eV. No one inhaling carbon monoxide can hope that the oxygen atom will break back off to let them breathe. Only the miracle of photosynthesis, with photons from the sun bombarding leaves, can break carbon dioxide back to absorb carbon and release oxygen. For nearly all leaders at Durban, it is too late for them to realize the consequences of this simple science. Instead they will be bent on deceiving each other with trick definitions and statistics.

A numerator begging for a denominator.

The uncanny miracle is that fuel seems to disappear once we use it. The gas tank gets empty. The log fire has gone up in smoke. Coal is reduced to cinders. That has been fine from cavemen days up to about 1970. Now science forces us to be aware that 12 grams of carbon combust resulting in 44 grams of carbon dioxide. Some greenies have suggested car drivers should be legislated to be forced to drive around with emissions stored in the car trunk, and delivered to a dump bank to pay a penalty when the weight of emissions gets too heavy. A car produces about 7 tons of emissions per year.

A more challenging science is to wonder, where does the released energy actually come from? Chemical engineers have a blasé answer which turns out to be quite superficial. At the level of single atoms and molecules, one molecule of the simplest fuel, natural gas, or methane (CH4) combusts with two molecules of oxygen and results in one molecule of carbon dioxide and two of water. The total of coulombic forces between carbon and hydrogen in the fuel, and between oxygen atoms in their molecules is 27 electronvolts. After combustion the new molecules have aggregate bond energy of 35 eV and 8 eV is “released”, and “available” for heating, or driving a car, or any economic use. A kilogram of any fuel gives off energy within the range of 14 to 46 megajoules – that is, wood, bread, natural gas, coal, butter, plant oil, gasoline, in ascending order.

It seems the inverse of common sense that in a fuel combustion equation, 27 eV becomes a larger number, 35 eV, with difference as the energy we need for economic activity. The answer to this puzzle has not been the goal of scientific inquiry up till now. At some future meeting after Durban, it will be a hot topic, and indeed the core subject. A molecule of methane has bonds that can be broken totaling a value equivalent to 27 eV. However there are other coulombic forces within the atoms that do not break in combustion, and in the molecules formed after combustion, there are more, tighter bonds, locking up the carbon. Chemists, if forced to address this phenomenon, will say the energy in those bonds is “unavailable”, and that entropy has increased. In the future, from a perspective of managing environment, instead of industrial engineers, economists, administrators and leaders talking about “energy produced” “energy demand” and “energy consumed”, a fuel will be defined by how much energy it can make available, and after use, how much energy is still there, locked up, and useless. For one methane molecule the numerator, 27, has a denominator estimated to be about 464 eV. After it is used, the result is the numerator 35 (as in conventional calculations) over a denominator of 456 eV. The economic process has driven entropy of 27/464 to 35/456, ie, an increase from 5.8% to 7.7%. The world “use” of energy from all economic sources was 450 exajoules in 2010. That is the numerator, and the denominator of “unavailable” energy is (my estimate) 26,000 exajoules. In some future, I imagine every individual has an “environmental footprint” meter measured as a numerator and denominator in joules on a LED screen on their forehead. The numerator says how many joules of usable energy they destroyed in their daily life, and the denominator shows where it went as waste into our common environment. A guy like Donald Trump, far from being admired, would be a pariah. Instead of fighting for and boasting over energy harnessed and used to power economic activity we should be humbly seeking ways to slow the entropy increase. One day in the future, after the conference in Durban has disintegrated into recriminations, there will be a Conference of Parties, and the parties will genuinely, and humbly, out of self interest seek aversion from the troubles suffered through global commitment to a safer environment.

: http://www.coulterexergy.com/archives/976

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