The use of energy by mankind has a glorious past and will certainly have a glorious future. The emergence and evolution of mankind has formed an indissoluble bond with energy. Energy has provided mankind with the material basis for survival and evolution. In the struggle against nature, mankind is constantly exploring new energy fields and developing energy conversion methods, so that human civilization is constantly advancing to a new level.
More than 1 million years ago, when primitive humans began to appear in the animal kingdom, they did not exceed the level of the biological kingdom in the use of energy. They only collected plants and captured small animals to satisfy their hunger, and stored them in animals and plants. "Bioenergy" converts the "mechanical energy" needed for human physical activities, which was the only way of using energy for humans at that time. What's interesting is that no matter how far humans evolve, this ancient way of using energy will continue forever.
Between 500,000 and 600,000 years ago, humans ended the childhood period called "Rumao Drinking Blood" and began a life of cooking food with fire. The first Mars that drilled wood to make fire was the advancement of human wisdom, and it illuminates the way for humanity to move forward. Drilling wood for fire is the process of human labor, which converts the mechanical energy of muscles into heat energy, and then uses fire to ignite firewood, which converts biological energy into heat energy through a chemical process (combustion). Humans use fire to cook food, heat and illuminate, and make bronzes and irons, which have made a huge leap in human material civilization.
In the second half of the 18th century, the British Watt invented the steam engine. Since then, coal has replaced the previous wood and has become the driving force for industrial and agricultural production. The invention of the steam engine promoted the industrial revolution of the bourgeoisie and rapidly developed handicraft production into machine production. This is another great change in the use of energy by mankind after drilling wood for fire. Drilling wood for fire made people know that mechanical energy can be converted into heat energy; and the appearance of the steam engine enabled people to realize the ideal of converting heat energy into mechanical energy.
Looking through the development history of human society, we can find that energy has forged an indissoluble bond with the progress of human society. The use of fire has ended the primitive life of mankind, which has not only transformed human beings themselves, made them smarter and stronger, but also promoted the development of social productive forces and the transformation of social structure. The invention and application of the steam engine is another milestone in the progress of energy science and technology. It ushered in the industrial revolution. Mankind ended the era of slash-and-burn cultivation and entered the era of large-scale industrial production, which greatly developed productivity.
In the 20th century, the application of electronic technology has once again greatly liberated the productivity of mankind, and the mythical miracle that people have longed for for thousands of years has begun to appear. For example, TVs known as "Shunfeng Er" and "Clairvoyance" have entered thousands of households, and various other household appliances have also made people's lives colorful, comfortable and convenient. The application of nuclear energy has given mankind a broader vision of developing nature. In the new long march that scientists have begun to open up the universe, nuclear energy has provided a huge source of power for interstellar navigation. The development, utilization and research of energy have received widespread attention from all over the world.
1. Energy is the pillar of the development of human society
Energy, as the name implies, energy refers to the source of energy. Energy can make objects do work, and the existence and movement of matter are inseparable from energy. Energy is widely present in the universe, and it is an essential material condition for the origin and evolution of life.
Energy often shows its power in the form of light, heat, electricity, magnetism, etc.; it can be solid, liquid, gas, or in the form of electrons, photons, and elementary particles; it can be inorganic, organic, or inanimate , Living body. Energy is widely distributed in the sky, the surface and the underground. Coal, oil, natural gas, hydropower, solar energy, wind energy, tidal energy, wave energy, ocean thermal energy, geothermal energy, and biomass energy are all familiar energy sources. Energy is closely related to human life, and people's clothing, food, housing and transportation are inseparable from it.
If there is no necessary and sufficient energy, mankind will lose the most basic living conditions, and life on the earth will end. Material life is inseparable from energy, and spiritual life is no exception. People need electricity to watch movies, listen to the radio, and watch TV; even the books, newspapers and periodicals that people read need energy to print. Moreover, with the development of society and economy, energy consumption is increasing.
Open the picture scroll of the history of science and technology development, and you will find that the development of science and technology is constantly advancing to the peak step by step. From the history of science and technology development since the 18th century, it can be seen that the several industrial revolutions experienced by human civilization are all closely related to the transformation of energy.
In 1769, the British inventor Watt, after more than ten years of hard research, made a series of major improvements to the original steam engine that had appeared at that time, improved the thermal efficiency and working reliability of the steam engine, and made the invention of the steam engine with condenser. The patent makes the steam engine an industrially applicable engine, and thus has been widely used. This form of thermal energy conversion led to the birth of the steam engine for large industrial power machinery. After that, Britain first completed the industrial revolution led by steam to promote textile machinery, and it quickly spread to the mining, machinery, metal and other industrial sectors, where there are steam engines. The factory was built intensively, and the steam age that has been inaugurated since then is a new age unmatched by the stoneware, pottery, and new bronze ages, and social productivity has achieved tremendous development. This is what people usually call the first industrial revolution, which started in the 1870s and was basically completed in the 1840s.
The second huge promotion of the development of science and technology is the emergence and application of electric energy. In 1866, the advent of Siemens generators had the same epoch-making significance as Watt's invention of the steam engine in the history of scientific and technological development, leading to the advent of a monopoly capitalist society.
The American inventor Edison first invented the tungsten filament electric lamp in 1879; an industrial-scale thermal power station was built in 1881, and electrical energy has been used on a large scale since then.
Picture: Tungsten filament lamp
Since the 1880s, due to the rapid development of electrical energy applications, capitalist monopolies have emerged in some countries with more developed industries. Emerging industries and products such as generators, electric motors, trams, electric cranes, wired telegraphs, telephones, wireless phones, electric furnace steelmaking (including copper and aluminum), nitrogen manufacturing, and ammonium nitrate fertilizer industries have all come out one after another.
From the end of the 19th century to the beginning of the 20th century, the use of electric energy became more extensive and larger, and the development of science and technology entered a brand-new "electric age". The science and technology of the 20th century has achieved remarkable results along the road of electrification. This is the so-called second industrial revolution. The result of this revolution was that the age of electricity replaced the age of steam.
During the Second World War, both belligerent countries mobilized science and technology to serve the war. In 1939, German scientist Hahn first discovered the "nuclear fission" of uranium;
In December 1942, Italian scientist Fermi presided over the completion of the world's first nuclear reactor at the University of Chicago in the United States, realizing that mankind was the first to ignite and control a "nuclear fire", and opened the prelude to the atomic age. The United States mobilized 150,000 people and spent a huge sum of US$2 billion. On July 16, 1945, the world’s first atomic bomb exploded for the first time. Nuclear energy has since become a blockbuster.
Compared with the chemical revolution, metallurgical revolution, electric power revolution, etc., the advent of nuclear energy has greater epoch-making significance. This is because mankind has found a new "fire". The discovery and application of "nuclear fire" have changed the energy needed for human life and production from almost all from the sun in the past to being obtained from the nuclear fuel (uranium, thorium, etc.) stored in the earth itself, and mankind has seen that it is finally obtained. The light of hope for endless energy.
Because nuclear energy is millions of times more powerful than ordinary chemical energy, it was first used by Wall Street bosses to create atomic bombs that are thousands of times more deadly than ordinary bombs, as well as new types of nuclear weapons such as hydrogen bombs and neutron bombs. The composition has undergone a fundamental change, and the strategic thinking has also undergone a fundamental change. In the competition, nuclear submarines and nuclear warships have come out one after another, becoming a powerful nuclear deterrent. After the war, the world's first nuclear power plant appeared, and it has sprung up rapidly, becoming a new force in the electric power industry. Nuclear heating and nuclear steelmaking have shown people the bright prospects of nuclear energy utilization. The application of radioisotopes has become a light industry in the nuclear industry. The use of nuclear energy opened the prelude to the third industrial revolution.
In modern times, with the birth and development of electronic computers, they have widely penetrated into all fields of human society, and this industrial revolution has further developed in depth, thus obtaining the development of space, the vigorous rise of synthetic materials, and the growth of robot teams. And other extraordinary achievements. With the progress of the third industrial revolution, mankind has entered the electronic age.
In contemporary times, a new industrial revolution marked by laser technology, microelectronics, microcomputers, optical fibers, new materials, life sciences, ocean development, and new energy discovery has emerged.
Energy provides human beings with a material basis for survival and evolution, is the most basic driving force for the development of the entire world and social and economic growth, and is the basis for human society to survive. Energy has witnessed the development of human society and has become a strong pillar and cornerstone of the development of human society.
What is energy? To understand energy, first come to understand energy.
What is energy? Energy is power, and energy exists in many forms, including mechanical energy that can make machinery work; chemical energy that can cause changes to produce chemical reactions; thermal energy that causes temperature changes to produce movement or changes; and can cause electric current to move and make it glow Or heat generated by electricity. Once the energy is used, it will be transformed from one form to another. For example, a turbine is formed in the water falling pool of a waterfall, which realizes the transformation from potential energy to mechanical energy. Mechanical energy drives the operation of the generator to generate electrical energy, which can then be used to generate electricity.
Energy comes from energy sources. For example, solar energy brings us light energy and heat energy, hydraulic energy produces mechanical energy and electrical energy, wood and coal can be used to provide energy, mechanical energy and electrical energy, oil and natural gas, it can drive generators, generate heat and other energy. Everything is working. For example: heating and cooling buildings, lighting houses and streets, powering vehicles, generating electricity, and driving industrial machinery to operate. Energy plays a key role in our lives. Over the years, we have discovered many ways to use energy to improve our lives. Energy is everywhere, sun, wind, wood, water, etc. In fact, these are all precious treasures that nature bestows on mankind. With the accelerated evolution of mankind and the continuous improvement of civilization, the ability of mankind to use natural energy is also rapidly developing. In ancient times, human beings learned to drill wood for fire in their survival, so as to win warmth and light for themselves in the difficult living environment. With the development of society today, people have mastered cutting-edge technologies such as atomic energy, and their applications have expanded from the realm of life to the military.
Energy is the material basis of human activities. In a sense, the development of human society is inseparable from the emergence of high-quality energy and the use of advanced energy technologies. In today’s world, with the progress of society, with the development of economy, with the improvement of people’s quality of life, the development of energy, the relationship between energy and the environment, and the relationship between energy and the environment, have become the common concern of the whole world and all mankind. The problem is also an important issue for China's social and economic development.
In human society, all materials that provide energy conversion to the natural world are energy, mineral-containing energy, nuclear physical energy, atmospheric circulation energy, geographical energy, etc.
Energy is a resource that can provide useful energy needed by mankind directly or through conversion. Human beings use energy sources other than their physical strength to start from drilling wood for fire. The initial sources of all forms of energy in the world are nuclear fusion, nuclear fission, sources of radiation, and the movement of planets in the solar system. The thermonuclear reaction of the sun releases extremely huge energy, the radiation energy that hits the earth's atmosphere is 174000TW/a, this kind of radiation actually provides inexhaustible energy for the earth and space. The thermal effect of the sun produces wind, water, and ocean energy. Fossil fuels such as coal, oil, and natural gas also indirectly come from solar energy. Biomass energy is the solar energy absorbed by plants through photosynthesis. The movement of the planets in the solar system produces tidal energy.
Picture: Solar Energy
The term "energy" was rarely talked about in the past. Due to the outbreak of the three global oil crises, energy has become a hot topic of discussion. Energy is the most basic driving force for the development of the entire world and social and economic growth, and it is the basis for the survival of human society. Since the Industrial Revolution, energy security issues have begun to appear. In the following two decades, with the support of stable energy supply, the size of the world economy has grown considerably. With the rapid development of the global economy today, the issue of international energy security has risen to a national level, and all countries have formulated energy policies with energy supply security as the core.
However, while enjoying the benefits of rapid economic development and technological progress brought by energy, mankind also encounters a series of unavoidable energy security challenges. Energy shortages, resource competition, and environmental pollution caused by excessive use of energy threaten mankind. Survival and development.
So, what exactly is "energy"? Regarding the definition of energy, there are currently more than 20 statements. For example: "Encyclopedia of Science and Technology" says: "Energy is a resource from which energy such as heat, light and power can be obtained"; "Encyclopedia Britannica" says: "Energy is a term that includes all fuels, flowing water, sunlight and wind , Humans can use appropriate conversion methods to make it provide themselves with the energy they need"; "Encyclopedia of Japan" says: "In various production activities, we use heat, mechanical energy, light energy, electrical energy, etc. to do work. The various carriers in nature that can be used as these energy sources are called energy"; China’s "Encyclopedia of Energy" says: "Energy can be directly or converted to provide humans with light, heat, power, etc. Energy carrier resources of form energy.” It can be seen that energy is a source of energy that takes many forms and can be converted to each other. To be precise and simple, energy is a material resource in nature that can provide humans with some form of energy.
Comprehensively speaking, we believe that energy refers to the general term for materials that can generate various kinds of energy (such as heat, electric energy, light energy, and mechanical energy) or can do work. Anything that can be directly obtained or obtained through processing and conversion to obtain useful energy. A variety of resources, including coal, crude oil, natural gas, coal-bed methane, hydropower, nuclear power, wind power, solar energy, geothermal energy, biomass energy and other primary energy and secondary energy such as electricity, heat, refined oil, and other new energy and renewable energy Energy, we collectively refer to energy.