Open Letter 3-2

Energy and Agriculture

Our brains prefer more energy. It is also sensitive to the fear of hunger. The agricultural characteristics of a good energy balance and the ability to store food that can be preserved were enough to attract our brain’s attention.

As agricultural life became established in some areas, the population of farmers began to grow as a steady supply of surplus food became available. As the new labor force continued to cultivate new land, farmland steadily expanded. The agriculturalists gradually overpowered the hunter-gatherers in terms of sheer force of numbers. Thus, the basis of human life gradually shifted from hunting and gathering to farming.

With the advent of agriculture, humankind was able to capture the solar energy that poured down on the earth on an unprecedented scale. As the amount of solar energy that could be captured increased dramatically, the labor force, the energy at mankind’s disposal, also increased in proportion to population growth.

This is an estimate based on research. At 12,000 years ago, when agricultural life had not yet begun, the world population was 5 to 6 million. Ten thousand years later, 2000 years ago, the world population had reached about 600 million. This means that the labor force at the disposal of humankind has increased approximately 100-fold since the beginning of agriculture. The effects of agriculture were enormous. The transition to an agrarian lifestyle, which brought about such non-linear changes, was the second energy revolution in human history, after the use of fire.

Darkness brought about by Agriculture

As the agricultural way of life became more established and widespread, a troubling problem arose. The problem was that people fought in groups to secure the solar energy that poured down on the land. In other words, the era of wars over the land, which continues to this day, has begun. The outbreak of war creates winners and losers. In ancient times, those who were defeated in battle were generally killed or enslaved to varying degrees.

In ancient societies, where labor was the number one source of energy at the disposal of mankind, there was tremendous value in enslaving people. Ancient civilized societies cannot be described without the existence of slaves. The upper class of citizens who led the civilization were able to obtain the sustenance they needed without having to engage in agriculture themselves by using the slaves of the lower class.

Life as an upper class person is an ideal environment for the human brain. This is because the brain is guaranteed to prioritize the use of energy taken into the body over muscles. The interest of the upper class human brain became directed toward philosophy and art, which are cultural activities not directly related to obtaining food.

The Story of Humbaba in the “Epic of Gilgamesh”

The story of Humbaba is found in the Epic of Gilgamesh. It is the oldest known story of mankind and an ancient heroic tale. It is also the world’s oldest written record of the destruction of nature by mankind.

King Gilgamesh, the hero of the “Epic of Gilgamesh,” was the actual king of Uruk, one of the leading city-states of the Sumerian civilization that flourished in southern Mesopotamia around 2600 BC. Desiring to gain immortal fame by building a magnificent city, he and his ally Enkidu decided to go into the forest and cut down a large number of cedars of Lebanon. The forest had a watchman, the demigod Humbaba, who guarded the forest by order from Enlil, the supreme god of Sumer.

King Gilgamesh and Enkidu entered the forest of cedars of Lebanon with metal axes, the symbol of civilization. At first, they were struck by the beauty of the forest, but eventually changed their minds and began to cut down the cedars of Lebanon.

Awakened by the sound of felling trees, Humbaba became enraged at the sight of the invaders and attacked King Gilgamesh, spitting fire from his mouth. After a fierce battle, Humbaba was defeated and his head was chopped off. Thus, the forest lost its guardian god and all the cedars of Lebanon were cut down.

Seeing this, Enlil, the supreme god, became enraged and announced that he would “turn the earth into fire and burn the food with fire,” warning of nature’s retribution. And true to his word, the sky god Anu caused a starvation for seven years.

Once set in motion, the desires of human society are not easily stopped. Therefore, Enlil, the supreme deity, needed Humbaba to protect the forest. However, the bare limestone mountainsides that cover most of the upper Lebanon Mountains indicate that the prayers of the story’s author were not heeded. Humbaba could not protect the forest because humans had killed him.

The civilized societies that mankind has built have involved extensive deforestation. Wood was used as building material for buildings and ships, and for baking pottery and bricks. It was also used as fuel in kilns for leaching metals. Let’s look at this from an energy perspective. The use of forest resources is equivalent to the use of solar energy that falls on the land. From the perspective of land use, forest resources were also used exclusively for human convenience, second only to agriculture.

In the case of cedar trees, a typical building material, it takes about 40 to 50 years to grow to a size where it can be used as a building material. For cypress trees, it takes about 50 to 60 years. This means that each mature cedar or cypress tree has 40 to 60 years of solar energy that has been stored in the land. It is no exaggeration to say that technological progress in civilized society has been supported by the supply of energy from the harvesting of forest resources.

The art of metallurgy, a symbol of civilized society, always required large amounts of charcoal due to the need to maintain furnaces at high temperatures. In the field of construction materials, fired bricks were invented to overcome the weakness of sun-dried bricks, which were vulnerable to rain, and baked gypsum was developed, in which gypsum is turned into cement by heating it. Charcoal and firewood were also consumed in the production of these materials.

The obvious environmental changes caused by deforestation could not have gone unnoticed by the ancient Mesopotamians. They were aware of the causal relationship between deforestation and desertification at some point in time and recognized the need for protection. Such awareness of the problem must have led to the creation of the Humbaba. However, they were unable to curb their desire for logging. This is the fear of the human brain, which always demands more energy. The humbaba, which was supposedly conceived to put a stop to their behavior, ended up being killed by the iconic symbol of civilization, the metal axe.

The mistake of clearing forests to the point of non-renewability and permanently altering the soil environment was repeated in the same way by civilizations around the world, not only the ancient Mesopotamian and ancient Greek civilizations. This was a major factor in the decline of many ancient civilizations. All societies that consumed resources faster than they could be regenerated were doomed in the long run to decline due to resource depletion.

Traces of Deforestation Seen in Japanese Temples

By the way, one might think that Japan, with its abundance of greenery, has nothing to do with such deforestation, but in fact Japan is no exception.

In Japan, the capital was relocated 21 times during the 200 years between the Asuka and Nara periods (circa 600-800 A.D.), from Emperor Suiko to Emperor Kanmu, and each time the nearby forests were cut down. Especially during the construction of the Heijo-kyo Capital, the building of huge wooden structures, led by Todaiji Temple, flourished. Combined with the casting of the Great Buddha statue at Todaiji, a large amount of wood was consumed.

As a result, natural forests with a mixture of coniferous and broad-leaved trees disappeared from the areas surrounding the capital, replaced by forests of red pine trees growing on thin land. The fact that the frequent relocation of the capital stopped after the construction of Heian-kyo is probably not unrelated to the rapid loss of forest resources in the areas surrounding the capital.

The perfection and diffusion of steelmaking technology created new problems

The year is 1709. An attempt to open the door to a new era began quietly in a blast furnace in the English Midwest. Abraham Darby, owner of a blast furnace in the Severn Valley, a region rich in coal and iron ore, began experimenting with the use of coal, which was abundant in the surrounding area, as an alternative fuel to wood and charcoal. Darby produced coke by dry distillation of coal to remove impurities. By burning this coke in a blast furnace, he created the coal-based iron manufacturing process.

Later, his son, Abraham Darby II, followed in his father’s footsteps, and made further trials and errors in his search for the ideal coke, while at the same time working to improve the blast furnace to achieve mass production. His efforts bore fruit, and in 1735, he perfected the technology of iron manufacturing using coke.

In 1781, when the Derby family was headed by its third generation, Abraham Derby III, the world’s first cast-iron arch bridge was built over the Severn Valley. In 1818, the Vulcan, a ship made of iron, was launched on the Forth Clyde Canal near Glasgow, Scotland. Iron began to replace wood in a variety of applications.

In this way, mankind was finally freed from the problem of limited growth due to depletion of forest resources that had plagued it since the birth of civilization. At the same time, however, the seeds of a new problem were sown: carbon dioxide emissions that would lead to global climate change.

Full-scale energy revolution

The invention of the practical steam engine is representative of the Industrial Revolution that began in England between the late 18th and 19th centuries. When one looks at the invention of the steam engine from an energy perspective, the first thing that comes to mind is that it marked the beginning of the coal age in earnest. But there is another reason to argue that the invention of the steam engine is truly revolutionary. It changed the form of energy.

In societies before the invention of the steam engine, humans used the energy they extracted in its original form without changing it. For example, consider cooking with fire or heating copper ore in a kiln furnace to melt copper. These use the thermal energy obtained from burning wood or charcoal to heat the foodstuff or copper ore. In other words, the thermal energy extracted from the wood or charcoal is used as-is as thermal energy. There is no change in energy form there.

So what does a steam engine do? In a steam engine, kinetic energy is extracted by moving pistons using the thermal energy of steam created by burning coal and heating water. There, the steam engine is converting the energy form from thermal energy to kinetic energy. The point where this energy conversion is realized is what makes the steam engine novel and innovative, different from any of the watermills, windmills, and other power machines invented by mankind up to that time.

Coal’s value as a heat source for steam engines led to the use of coal. The main actor leading the third energy revolution during the Industrial Revolution was the invention of the practical steam engine, which made energy conversion possible, not coal.

Discovering ways to enable energy transfer and conversion

The fourth energy revolution began in Vienna, the capital of the Austro-Hungarian Empire during the Habsburg rule, at the 1873 World’s Fair. In a corner of the glamorous Expo site, a man was preparing to display a power generator he had developed himself. He was a Belgian named Zenobe Gramm. The generator he had developed was the most powerful and stable output ever, and it was a work of which he was very proud.

While placing a generator next to the steam engine and wiring copper wire 500 meters away from it, a subordinate engineer accidentally connected the copper wire to another generator. When he operated the steam engine without realizing it, something unexpected happened. The armature of the generator connected by the copper wire started spinning. The genius engineer Gramm saw this and immediately realized what was happening. He realized that electricity could be used to easily transfer energy.

Although the steam engine was a great invention that brought about the third energy revolution, the place where heat energy was extracted and the place where the converted kinetic energy was consumed had to be the same. The use of electricity had the power to bring not only freedom in energy conversion, but also freedom from the constraints of place. This realization of Gram’s was the decisive factor in ushering in the age of electricity. It was the moment when the curtain rose on the fourth energy revolution.

Will organic fertilizers bring peace in the Edo period?

During the Edo period (1603-1868), Japan enjoyed 265 years of peace and prosperity, despite a doubling of the population, making it one of the most remarkable societies in the world. In addition to the development of new rice paddies, the supply system of fertilizers was solid, and crop yields steadily increased, which contributed greatly to the stability of the society. From the satoyama near the villages, fallen leaves and undergrowth were regularly harvested to obtain compost.

In cities such as Edo and Osaka, a system was established whereby farmers from the suburbs would come to the city to sell vegetables, and on their way home they would receive human excrement to use as fertilizer. The human excrement was not collected for free, but was paid for as a valuable commodity. Takizawa Bakin, author of “Nanso Satomi Hakkenden,” wrote in his diary that each adult received 50 eggplants in summer and 50 dried radishes in winter.

# “Nanso Satomi Hakkenden” is a full-length novel written by Bakin Takizawa in the late Edo period.

The diary of Kempel, a German doctor who stayed at the Dutch trading post in Nagasaki during the reign of Tsunayoshi Tokugawa, the fifth shogun, and twice accompanied the head of the trading post on his visits to Edo (present-day Tokyo), recorded the following. It is recorded that neighboring farmers eagerly searched for horse manure that had fallen along the roadside and brought it back home, and even collected old straw sandals and broken horse harnesses discarded by travelers to be used as compost. The Edo period was the ultimate recycling society.

From the mid-Edo period (around 1700) onward, fish manure, which was lighter and more nutritious than human excrement, became widely available. Wholesalers specializing in fish manure began to flourish, and the Boso Peninsula in Chiba became a major producer of fish manure, which was made by drying sardines and then grinding them into powder. The driving force behind the trade with Ezochi (present-day Hokkaido), made famous by the activities of Takataya Kahei, was the trading of fish fertilizer made from herring, which was abundantly available in Ezochi. Thus, as fertilizers became widely available on the national distribution network, agricultural productivity increased in areas with low population densities and low supplies of human and horse excrement, thus supporting population growth.

Completion of the ultimate recycling society

Fertilizer in Japan during the Edo period (1603-1868) consisted human excrement and fish manure, all of which are organic compounds derived from living organisms of the same period. No fossilized materials were used. In addition, since Japan was closed to the outside world during the Edo period and trade with foreign countries was limited, there was almost no procurement of food from overseas. These facts indicate that Japan in the Edo period was a perfectly recycling-oriented society that relied solely on solar energy, which fell daily at its feet, as its energy source. By recycling thoroughly, the Japanese of that time were building a sustainable, recycling-oriented society, which is the goal of today’s society.

The recycling-oriented society of the Edo period (1603-1868) also nurtured the spirituality of the Japanese people. It is the spirit of diligence. Throughout the Edo period, land that could be cultivated was almost completely achieved. In agricultural production, human excrement and fish manure became widespread and were distributed throughout the country, so there was an ample supply of fertilizers. What could be done to further improve productivity? The answer is obvious: diligent work. Many agricultural books were published during the Edo period (1603-1867), and they always say that diligence is good. The teachings of Sontoku Ninomiya, who was active in the late Edo period (around 1800) in Sagami Province, now Kanagawa Prefecture, are a typical example.

Why has Japan’s population quadrupled?

The population of Japan in the late Edo period (1603-1867) was estimated to be about 30 million. What this means is that the population that the land of Japan can support, even in a completely recycling-oriented, cyclical society, would be about 30 million. Even during the Edo period, when the population continued to grow while building the ultimate recycling-oriented society, the decline in forests and mountains became more pronounced in the latter half of the Edo period, and the growth of the population was approaching its limits.

The current Japanese population of just over 120 million is four times the size of the population during the Edo period. How did the 90 million people increased after the Meiji period come to be fed? The first thing that comes to mind is the impact of food imports from overseas trade. Certainly, modern Japan is dependent on food imports. The food self-sufficiency rate on a calorie basis fell below 50% for the first time in 1989 and has dropped to 37% in 2018 results. This explains where it comes from for food equivalent to 60 million people, half of Japan’s current population.

On the other hand, this fact also indicates that the remaining 60 million people who are not dependent on imported food are dependent on food supplied by the Japanese land. The population of 30 million people could be fed by Japan’s land, which was developed to the utmost limit in the late Edo period (around 1800) to realize the ultimate recycling society, so 60 million people would mean a doubling of the population.

Hokkaido is one example of land that has been newly cultivated since the Meiji period, but I do not believe that this alone can explain the doubling of the population. How could Japan’s land have nearly doubled in productivity since the Meiji period? To understand why, we need to know the story of another society that developed on the other side of the ocean. That is the path leading to the Fifth Energy Revolution.

Lord Crookes’ Historic Speech

At the end of the 19th century, Sir William Crookes, newly appointed president of the British Academy of Sciences, was one of the leading scientists of his day, known for his discovery of the element thallium and his work on cathode rays. On the occasion of his election as President of the British Academy of Sciences in 1898, Sir William Crookes delivered what was later considered a historic address. In his speech, he pointed out that there was no longer any unimproved land left on earth suitable for agriculture, and that a large supply of fertilizers was needed to support a growing population.

He then warned that the supply from natural mineral resources, such as Chilean nitrate, would not be sufficient to meet the demands of the 20th century. According to his estimates, Chilean nitrate would be depleted as early as the 1920s and as late as the 1940s. So what should be done? Lord Crookes had an answer for the most important question that science would have to tackle in the future. His answer was that “we should develop a technology to fix nitrogen from the air.”

Fertilizer Identity

In the early 19th century, methods of chemical analysis were being developed in Europe, and various substances and elements were being discovered. The German chemist Justus von Liebig was the first to elucidate the nutrients in plants. Germany was a leader in chemistry at the time, and because German land was the leanest in Europe, there was a great interest in fertilizers, which led to Germany leading the world in fertilizer analysis.

Liebig used chemical analysis to determine that nitrogen, phosphorus, and potassium were the main components of fertilizers. He argues that nitrogen, phosphorus, and potassium can be applied directly without the use of composted organic matter. Substances that are not derived from living organisms are called inorganic substances. This was proven by the success of hydroponics without soil.

There are generally a total of 14 nutrients that have been revealed through such chemical analysis, including metallic elements that are used only in trace amounts. Among them, three elements, nitrogen, phosphorus, and potassium, which Liebig discovered through his analysis of fertilizers, are widely known as important elements that have a significant impact on plant growth due to their high requirements. Today, they are also referred to as the three elements of fertilizer.

Technology for making bread from water, lime, and air

Of the three elements of fertilizer, nitrogen was the target for consideration for chemical synthesis. While phosphorus and potassium continued to rely on mineral resources, nitrogen was the only element that did not have to rely on mineral resources such as Chilean nitrate, because it was equally available to all in inexhaustible supply. Four-fifths of the air is composed of nitrogen. This is precisely what Lord Crookes pointed out in his 1898 speech.

At the time of Lord Crookes’ speech, in the late 19th and early 20th centuries, mankind’s knowledge of chemistry had advanced by leaps and bounds. It was already known how to synthesize ammonia by placing hydrogen and nitrogen in a reaction vessel, keeping the temperature low and the pressure high.

German scientist Fritz Haber won the race to develop the technology to produce ammonia. His experimental apparatus was designed to withstand the harsh conditions of a reaction vessel at 200 atmospheres, and he also devised a system to quickly separate the ammonia produced. Using this well-thought-out experimental apparatus, he tested a number of catalysts and found that osmium, a precious metal, could be used as a catalyst to produce ammonia in sufficient quantities to be industrialized. He also continued to research alternatives to the scarce osmium and concluded that a mixture of iron, aluminum, and potassium components found in Swedish magnetite was the most effective catalyst.

By 1911, the Bosch-led BASF team was producing more than two tons of ammonia a day from a temporary plant, and two years later they completed a full-scale plant in the southwestern German town of Oppau. Thus, in just 15 years after Lord Crooks’ speech, mankind had acquired the technology to fix nitrogen. The nitrogen fixation technology, known as the Haber-Bosch process, which they perfected through their efforts, was called “the technology to make bread from water, lime, and air,” and was highly praised at the time. Thus, the curtain rose on the fifth energy revolution, in which large amounts of energy were used to increase food production.

The Haber-Bosch process has brought

The result of these artificial fertilizers was an explosive increase in population. There was a certain limit to the amount of nitrogen that could be fixed in nature. The Haber-Bosch process has released the yoke of the natural world. By fixing nitrogen in the air one after another, the total amount of living organisms, including humans, that can survive on the earth at the same time has expanded dramatically.

By the mid-20th century, high-yielding varieties developed on the premise of ample fertilizer supplies became widespread, and grain yields from farmland increased dramatically. This “Green Revolution” supported explosive population growth: from only 1.6 billion at the beginning of the 20th century, the world’s population exceeded 2.5 billion in 1950, and by the end of the 20th century it had surpassed 6 billion. The growth of the world’s population over the past century, and especially in the half century following World War II, has been astonishing.

This is also the reason why Japan, which had promoted a recycling-oriented society to the utmost limit during the Edo period, was able to further increase its population after the Meiji period. After the Meiji period, Japan actively adopted new technologies and promoted a shift from a traditional recycling-oriented society centered on agriculture to a resource-intensive society centered on industry and mass consumption of resources, as in the West. The profits from exporting industrial products allowed Japan to import food, and the industrialization of agriculture, which began with the use of artificial fertilizers, increased the yield of domestic agricultural products, which in turn allowed for further population growth.

According to Vaclav Smil of the University of Manitoba, Canada, if the Haber-Bosch process had not been invented, two out of every five people living on earth today would not exist. Put another way, every human being alive today depends on the nitrogen atoms fixed by the Haber-Bosch process for 40% of his or her body. Every one of us alive today is a beneficiary of the Haber-Bosch process.

Energy Diversity

One of the reasons that energy issues have become so difficult is that it is difficult to get a clear and accurate picture of what energy really is in the first place. The human race’s unparalleled intelligence has enabled us to imagine things that we cannot see or even touch, but when we try to describe these things in words, we inevitably end up with something abstract.

Galileo Galilei, a pioneer in the study of scientific energy, struggled with how to describe the forces that bring about motion in his study of the laws of motion and used a number of similar terms for force, including impetus, moment, and force.

Even today, the world of science still uses various expressions such as kinetic energy, potential energy, thermal energy, electrical energy, light energy, nuclear energy, and chemical energy. There are so many related units of measurement, starting with joules, calories, and ergs, but also kilowatt hours, which are commonly used in the electrical field, barrels of oil, and BTUs (British thermal units) for natural gas. This phenomenon occurs because energy can take many forms. As the best measurement methods were devised for each form of energy, the number of units to measure energy increased.

Etymology of Energy

Let us consider the origin of that word, energy. It is a word that we use in our daily lives without thinking about it, because it often contains profound insights from those who have gone before us. The word energy comes from the Greek word ergon, meaning “work.” To this ergon, the prefix (en) was added to create the word energos, meaning “active state,” which in turn gave rise to the word energeia, meaning “activity.”

Based on this, the English word “energy” was created as a scientific term in the 19th century. In Japan, it was imported from Germany in the Meiji era (1868-1912) as one of the technical terms using cutting-edge science. This is the reason why the German reading “energy” has taken root in Japan instead of the English reading “energie”.

We live in the modern age, and we know something that the Japanese of the early Meiji period, when they first encountered the word energy, did not know. That mass and energy are equivalent, i.e., an object is a mass of energy. This is a fact revealed by Einstein’s special theory of relativity, known as the world’s most famous physics formula (\(E = mc^{2}\)). This formula was published in 1907, the 40th year of the Meiji era.

Aristotle’s Dunamis and Energeia

Westerners, who have made great advances in science, understood energy in a firsthand sense before Galileo and Newton came along. For example, the ancient Greeks had the word Dunamis. The word means potential ability or skill. Aristotle, a giant of intellect active in the 4th century B.C., drew attention to this word.

The basis of his thought was to systematically summarize all movements and changes in nature. He notes that every movement or change has a beginning and an end. Among other things, he focused on the end. He saw the end as the state in which a thing has achieved its purpose through movement or change. For example, when he saw the transformation of a plant from seed to germination to flowering, he thought: “The seed expresses its intrinsic power. “The seed has achieved its purpose through the expression of its inherent power.”

Aristotle called the potential of these seeds Dunamis, and the state in which they reached their goal and became a flower was called Energeia, a word coined from Energos, the state of being at work. Dunamis eventually became the root of the English word Dynamic, meaning force or dynamic. The word Dunamis was also used to refer to the energy stored in a thing.

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