New energy history

Three elements of human survival and development

Material, energy and information.

Therefore, the development history of energy directly affects the development history of mankind.

The most decisive elements in our human survival and development are three: matter, energy and information.

Our world is composed of matter; human survival activities are determined by the recognition and response to information; and maintaining life and engaging in development activities must be carried out by consuming energy.

All energy comes from energy, and humans cannot do without energy. Energy is the main basis for human survival, life and development. Energy science and technology, and the development of energy utilization have always played an important role in the progress of human society.

Milestones in Energy Development It can be said that every milestone development in energy utilization is accompanied by a huge leap in human survival and social progress. For thousands of years, the history of human energy utilization has roughly gone through four milestone stages of development: the use of fire in primitive society, where ancestors ushered in the dawn of civilized society under the light of fire; the invention of the steam engine in the 18th century and utilization, greatly improved productivity and led to the Industrial Revolution in Europe; the use of electric energy in the 19th century greatly promoted social and economic development and changed the face of human life; the use of new energy represented by nuclear energy in the 20th century made Human beings entered the microscopic world of atoms and began to utilize the energy inside atoms.

Future energy requirements

Have sufficient reserves to meet the needs of human survival and development, and will not cause environmental pollution problems that affect human survival.

Future demand for energy In the future, human society will still rely on energy and the sustainable development of energy. Therefore, we must now clearly understand the energy structure and reserves on the earth and develop the energy utilization technologies that must be developed so that human survival can be maintained permanently.

And the energy we rely on for survival is inexhaustible? The answer is: no, also. In fact, after entering the 21st century, the energy resources currently exploitable by human technology are facing a serious shortage crisis. Today's fossil fuel resources such as coal, oil and natural gas are increasingly depleted and cannot even be sustained for decades. Therefore, sustainable alternative energy sources must be found. The peaceful use of nuclear energy in the past half century has made nuclear energy the only realistic large-scale energy source among the new energy family that can replace limited fossil fuels. Moreover, if nuclear energy can be fully utilized in the future, human energy will be unlimited.

In addition to the three major factors of matter, energy and information, human beings’ requirements for security are also becoming more and more important. Safety includes social safety, health safety and environmental safety, etc. They are also closely related to energy. The energy currently used has caused a lot of environmental pollution problems and seriously affected human survival. Therefore, the requirement for energy in the future will not only be sufficient reserves, but also clean energy. Compared with other fossil energy sources, the peaceful use of nuclear energy has fully proved that nuclear energy is one of the cleanest energy sources.

u The definition and source of energy

What exactly is "energy"? "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 resource that includes all fuels, running water, sunlight, and wind." In terms of the term, human beings can use appropriate conversion methods to allow it to provide themselves with the energy they need." It can be seen that energy is a source of energy in various forms that can be converted into each other. In short, energy is a material resource in nature that can provide energy to humans.

The source of energy

Energy from celestial bodies other than the earth (such as solar energy), energy contained in the earth itself (such as geothermal, nuclear energy), energy generated by the interaction between the earth and other celestial bodies ( such as tides).

Energy is the source of energy.

People usually classify energy according to its form and application. Generally divided into: solid fuel, liquid fuel, gas fuel, water energy, electric energy, solar energy, biomass energy, wind energy, nuclear energy, ocean energy and geothermal energy. Among them, the first three categories are collectively referred to as fossil fuels or fossil energy. These energy sources that have been recognized by humans can be converted into various forms of energy that people need under certain conditions. For example, firewood and coal, when heated to a certain temperature, can combine with oxygen to release a large amount of heat energy, which can be used directly for heating, or can be used to generate steam to drive a steam turbine and then drive a generator, turning the heat energy into mechanical energy and then into electrical energy. Electricity is sent to factories, institutions and households, and can be converted into mechanical energy, light energy or heat energy.

On the earth we live on, energy comes in all shapes and sizes. In summary there are three initial sources.

Solar energy

Earth

Energy from celestial bodies outside the earth (mainly solar energy). Most of the energy required by humans comes directly or indirectly from the sun. It is through photosynthesis that various plants convert solar energy into chemical energy and store it in the plant body. Fossil fuels such as coal, oil, and natural gas are also formed from ancient plants and animals buried underground over a long period of geological time. They are essentially solar energy fixed by ancient creatures. In addition, water energy, wind energy, wave energy, ocean current energy, etc. are also converted from solar energy.

The energy contained in the earth itself usually refers to the energy related to the thermal energy inside the earth and the energy related to the nuclear reaction.

The energy related to the thermal energy inside the earth is called geothermal energy. Hot springs and lava from volcanic eruptions are manifestations of geothermal heat. The earth can be divided into three layers: crust, mantle and core. It is a large heat reservoir. The crust is a layer on the earth's surface, generally ranging in thickness from a few kilometers to 70 kilometers. Below the crust is the mantle, which is mostly molten magma and is 2,900 kilometers thick. Volcanic eruptions generally erupt this part of the magma. The interior of the earth is the core, and the core temperature is 2000 degrees. It can be seen that the geothermal resource reserves on the earth are also very large.

The energy related to atomic nuclear reactions is the nuclear energy that this book will introduce. When the structure of the atomic nucleus changes, it can release a large amount of energy, which is called nuclear energy, or nuclear energy for short, commonly known as atomic energy. It comes from nuclear fission energy resources when uranium, plutonium, etc. stored in the earth's crust undergo fission reactions, and from nuclear fusion energy resources when deuterium, tritium, lithium, etc. stored in the ocean undergo fusion reactions. These substances release energy when nuclear reactions occur. At present, the largest use of nuclear energy is to generate electricity. In addition, it can also be used as other types of power sources, heat sources, etc.

The energy from the gravity of the planet refers to the energy formed due to the interaction between the earth and the moon, the sun and other celestial bodies. The regular movement between the earth, the moon, and the sun causes periodic changes in relative positions. The gravitational force between them changes accordingly, causing the sea water to rise and fall, forming tidal energy. Compared with the above two types of energy sources, the amount of tidal energy is very small. The world's tidal energy is converted into about 3 billion tons of coal per year, but what is actually available is only that part of the shallow sea area, which can be converted into about 60 million tons of coal per year.

u Energy structure and reserves

What energy resources are available for us to use on the earth? How long will they last? What should we do?

Types of energy

Primary energy: natural energy resources such as coal, oil, and nuclear energy;

Secondary energy: artificial manufacturing such as gasoline, electricity, steam, etc. Energy resources,

Primary energy and secondary energy Energy is divided into two categories: natural energy (primary energy) and artificial energy (secondary energy) according to the way it is generated. Natural energy refers to energy resources that exist in natural forms in nature and have not been processed or converted, such as coal, oil, natural gas, nuclear fuel, wind energy, water energy, solar energy, geothermal energy, ocean energy, tidal energy, etc.; artificial energy is It refers to the direct or indirect conversion of primary energy into other types and forms of energy resources, such as gas, gasoline, kerosene, diesel, electricity, steam, hot water, hydrogen, laser, etc.

Conventional energy and new energy. Among them, the energy that has been widely used by humans and played an important role in human life and production is called conventional energy, which usually refers to coal, oil, natural gas, water energy, etc. Four kinds. Energy resources that have only recently been developed and utilized by humans and await further research and development are called new energy. Compared with conventional energy, new energy has different contents in different historical periods and technological levels. In today's society, new energy usually refers to nuclear energy, solar energy, wind energy, geothermal energy, hydrogen, etc.

The Era of Coal

Changes in Energy Structure Historically, with the discovery and large-scale mining and application of new fossil resources, the world's energy consumption structure has experienced several changes. In the 18th century, coal was used to replace firewood. By the mid-19th century, coal had gradually become dominant. In the 1920s, with the discovery of oil resources and the development of the oil industry, the world's energy structure underwent a second transformation, from coal to oil and natural gas. By the 1960s, oil and natural gas had gradually become the dominant energy source. , shaking the dominance of coal. However, the outbreak of two oil crises since the 1970s began to shake the dominance of oil in energy. At the same time, the reserves of most chemical energy sources are decreasing day by day, accompanied by many environmental pollution problems.

Humanity's demand for energy is increasing day by day. For example, the estimated reserves of the major energy forms of Earth's energy

Coal: ~200 years

Oil and natural gas: ~50 years

Nuclear energy: infinite

One of the electricity consumption is increasing year by year. According to statistics, if the population doubles every 30 years, the demand for electricity will double every eight years.

As a result, at the end of the 20th century, the energy structure began to undergo the third transformation, that is, from an energy system centered on oil to a diversified energy structure based on coal, nuclear energy and other renewable energy sources. In particular, as time goes by, the proportion of nuclear energy will continue to grow and will gradually replace oil and natural gas to become one of the main large-scale energy sources.

The storage capacity of chemical energy. How many years will it take for coal, oil, and natural gas to be exploited and utilized by humans? According to statistics from the World Energy Conference, the world's proven recoverable coal reserves total 1.598 billion tons, and it is expected that it can be mined for another 200 years. The total proven recoverable oil reserves are 121.1 billion tons, and it is expected that it can be exploited for 30 to 40 years. The proven recoverable natural gas reserves total 119 trillion cubic meters and are expected to be exploitable for another 60 years.

It must be pointed out that it is a pity that coal, oil, etc. are directly burned to produce electricity and heat. Not to mention the possible environmental pollution, they are still very good chemical raw materials!

The potential of water energy and new energy What about water energy? We know that hydraulic power can be developed and utilized in the long term. But what should we do in those countries and regions with large areas of water shortage and insufficient water resources? Besides, there is also a seasonal problem with water energy. All these prevent hydropower from becoming the only main force in the world's energy structure. Among new energy sources, although solar energy is inexhaustible, the cost is too high, and judging from the current technological development, it is impossible to develop rapidly and be widely used within a generation. The same is true for other new energy sources. Some other energy sources are similar to water energy, and their scale is limited by environment, season, geographical location and other conditions, such as wind energy, tidal energy, geothermal energy, etc.

Fissile nuclides

There are only three types of atoms that are prone to fission: uranium-235 (U235), plutonium-239 (Pu239), and uranium-233 (U233). The only naturally occurring fissile element is uranium-235, plutonium-239 can be produced from uranium-238, and uranium-233 can be produced from thorium-232 (Th232).

Easy fusion nuclear reaction

Deuterium (D2)-tritium (D3) reaction. Deuterium and tritium are both isotopes of hydrogen atoms. Deuterium occurs naturally, while tritium is rare and must be produced artificially (for example, from lithium).

Nuclear energy - infinite energy Nuclear energy is divided into two types: fission energy and fusion energy. At present, only fission energy is used for peaceful purposes by humans. Controllable fusion energy utilization technology is being conquered.

The composition of natural uranium

99.3% of natural uranium is uranium-238, which is difficult to fission, and only 0.714% is uranium-235, which is easy to fission. Uranium-238 can be converted into fissionable plutonium-239 by absorbing a neutron.

Uranium, one of the main raw materials for the development of nuclear fission energy, has proven uranium reserves in the world of approximately 4.9 million tons and thorium reserves of approximately 2.75 million tons. If used well, it can be used for 2400 to 2800 years.

The fusion reaction mainly comes from the deuterium-tritium nuclear reaction. Deuterium can come from seawater in large quantities, and tritium can come from lithium. Therefore, fusion fuel is mainly deuterium and lithium. The content of deuterium in seawater is 0.03 g/L. It is estimated that the amount of seawater on the earth is about 13.8 billion cubic meters, so the world’s deuterium reserves are about 4 billion tons; Although lithium reserves are much smaller than deuterium, there are still more than 200 billion tons. Using it to produce tritium is enough to meet human needs for fusion energy. The energy released by these fusion fuels is tens of millions of times greater than the total energy released by the world's existing energy sources. According to the current level of world energy consumption, the deuterium and tritium available for nuclear fusion on the earth can be used by humans for hundreds of billions of years. If humans achieve controllable nuclear fusion of deuterium and tritium, nuclear fuel will be “inexhaustible and inexhaustible”, and humans will fundamentally solve the energy problem. This is exactly what current nuclear scientists are striving for. Fusion energy is not only abundant, but also safe and clean. Fusion produces much less radioactivity than fission.

Experts predict that nuclear energy will become an inexhaustible and lasting energy source for mankind in the future.

1.2 A Dirty Earth and Clean Nuclear Power

Key points of this section: Answer the following questions: How long can existing energy sources last? Can energy be used without polluting the environment? Is nuclear power really a sustainable energy source?

u Sustainable development of energy

It is necessary to find some energy sources that can ensure long-term sufficient supply without causing environmental pollution.

The current problems facing mankind are: depletion of energy resources; serious environmental pollution.

Energy Utilization and Environmental Sustainable Development

Energy Crisis

At present, some conventional energy reserves in the world can only last half a century (such as oil) , at most it can sustain the needs of human survival for one or two hundred years (such as coal).

Today, almost all industrialized countries face two closely related challenges related to sustainable development: ensuring a satisfactory long-term energy supply and reducing the environmental impact of human activities. The sustainable development of energy utilization and environment has become an important issue related to the future survival of mankind and the continuation of civilization.

Energy Supply Crisis Today’s world population has exceeded 6 billion, more than twice the amount at the end of the last century, while energy consumption has increased more than 16 times according to statistics. No matter how many people talk about "saving" and "utilizing solar energy" or "drilling more oil or gas wells" or "discovering more and larger coal fields", the supply of energy has never kept pace with human demand for energy. Currently, world energy consumption is dominated by fossil resources. A few countries such as China are dominated by coal, and most other countries are dominated by oil and natural gas. Based on current consumption, experts predict that oil and natural gas can only last for less than half a century at most, and coal can only last for one or two hundred years. Therefore, no matter what kind of conventional energy structure it is, the energy crisis faced by mankind is becoming increasingly serious.

Thermal power plants billowing with smoke

Energy pollution on the environment. On the other hand, especially the process of using fossil energy, it also directly affects the earth's environment, causing serious damage to the atmosphere and water resources. pollute.

The five main pollutants in the atmosphere are: nitrogen oxides (such as NO and NO2), sulfur dioxide (SO2), various suspended particulate matter, and carbon monoxide (CO). The main source of air pollution

Currently the world’s largest Serious air pollution comes from the increase in the amount of carbon dioxide in the atmosphere caused by the burning of fossil energy. The main consequences are: acid rain, greenhouse effect and ozone layer destruction.

And hydrocarbons (such as CH4, C2H6, C2H4, etc.). Its sources mainly come from three aspects: ① The combustion of fossil fuels such as coal and petroleum; ② The exhaust gas emitted by automobiles; ③ The exhaust gas generated by industrial production (such as various chemical plants, coking plants, etc.). Among them, thermal power plants burning fossil fuels are the largest stationary source of pollution.

1. Diversification

The world's energy structure has gone through the eras of fuelwood, coal and oil, and is now changing to natural gas. , at the same time, hydro energy, nuclear energy, wind energy, and solar energy are also being used more widely. Sustainable development, environmental protection, energy supply costs and structural changes in available energy determine the pattern of global energy diversification development. Natural gas consumption will steadily increase, and in some areas, gas-fired power plants will replace coal-fired power plants. In the future, while developing conventional energy, new energy and renewable energy will receive attention. In the EU's 2010 renewable energy development plan, wind power should reach 40 million kilowatts and hydropower should reach 105 million kilowatts. The "Energy White Paper" published by the British government in early 2003 determined the new energy strategy. By 2010, the proportion of renewable energy power generation in the UK will increase from the current 3% to 10% of the UK's total power generation, and by 2020 it will reach 20%. %.

2. Cleanliness

With the advancement of new energy technologies and increasingly stringent environmental standards in the world, the world's energy will further develop in the direction of cleanliness in the future. Not only the energy production process To achieve cleanliness, the energy industry must continue to produce more and better clean energy, and the proportion of clean energy in total energy consumption will gradually increase. In the world's energy consumption structure, the proportion of coal will drop from the current 26.47% to 21.72% in 2025, while the proportion of natural gas will increase from the current 23.94% to 28.40% in 2025, and the proportion of oil will remain at 37.60% to 37.90%. % level. At the same time, the use of coal and traditional energy sources such as firewood, straw, and manure, which were considered "dirty" energy in the past, will develop towards cleanliness. Clean coal technology (such as coal liquefaction technology, coal gasification technology, coal desulfurization and dust removal technology) , biogas technology, biodiesel technology, etc. will achieve breakthroughs and be widely used. Some countries, such as France, Austria, Belgium, and the Netherlands, have closed all their domestic coal mines and developed nuclear power. They believe that nuclear power is an efficient and clean energy that can solve the problem of greenhouse gas emissions.

3. Efficiency

The efficiency of energy processing and consumption in the world varies greatly, and there is huge potential for improving energy utilization efficiency. With the advancement of new energy technologies in the world, the world's energy utilization efficiency will gradually increase in the future, and energy intensity will gradually decrease. For example, based on constant prices in 1997 U.S. dollars, the world's energy intensity in 1990 was 0.3541 tons of oil equivalent/thousand U.S. dollars. In 2001, it had dropped to 0.3121 tons of oil equivalent/thousand U.S. dollars. It is expected to be 0.2759 tons of oil equivalent/thousand U.S. dollars in 2010. In 2025, it will be 0.2375 tons of oil equivalent/thousand US dollars.

However, energy intensity varies greatly in various regions of the world. For example, in 2001, the energy intensity of developed countries in the world was only 0.2109 tons of oil equivalent/thousand US dollars. From 2001 to 2025, the energy intensity of developing countries is expected to be It is 2.3 to 3.2 times that of developed countries, which shows that the world's energy saving potential is huge.

4. Globalization

Due to the uneven distribution of energy resources and demand in the world, it has become increasingly difficult for various countries and regions in the world to rely on their own resources to meet their domestic needs. Demand will increasingly rely on the supply of resources from other countries or regions in the world. The volume of world trade will become larger and larger, and the trade volume will gradually increase. Taking oil trade as an example, world oil trade volume increased from 1.22 billion tons in 1985 to 2.12 billion tons in 2000 and 2.18 billion tons in 2002, with an average annual growth rate of approximately 3.46%, exceeding world oil consumption of 1.82% during the same period. average annual growth rate. In the foreseeable future, the world's net oil imports will gradually increase, with an average annual growth rate of 2.96%. It is expected to reach 29.3 million barrels/day in 2010, 40.8 million barrels/day in 2020, and 48.5 million barrels/day in 2025. The globalization process of world energy supply and consumption will accelerate, and the world's major energy producing countries and energy consuming countries will actively join the globalization process of energy supply and demand markets.

5. Marketization

Since marketization is the best means to optimize the allocation and utilization of international energy resources, with the development of the world economy, especially the market-oriented reforms in various countries around the world As the process accelerates, the world's energy utilization becomes more and more market-oriented. Governments around the world will have fewer and fewer direct interferences in energy utilization, and the role of governments in serving the energy market will increase accordingly, especially in improving countries, The government will play a better role in regulating energy laws and regulations in various regions and providing a good energy market environment. Currently, countries rich in energy resources such as Russia, Kazakhstan, and Libya are constantly improving their national energy investment policies and administrative management measures. The degree of marketization and standardization of energy production in these countries will be improved, which is conducive to investment by foreign investors. .

3. Enlightenment and Suggestions

1. Rely on scientific and technological progress and policy guidance to improve energy efficiency and follow the path of efficient and clean energy utilization

China’s state-owned enterprises Our own national conditions, the characteristics of China's energy resource reserve structure and the characteristics of China's economic structure determine that in the foreseeable future, my country's energy structure dominated by coal will be unlikely to change. The difference between my country's energy consumption structure and the world's energy consumption structure will continue to exist, which requires China's energy policies, including policies in energy infrastructure construction, energy exploration and production, energy utilization, environmental pollution control and the use of overseas energy, to be different from other countries. In view of my country's large population, limited energy resources, especially high-quality energy resources, and the fact that it is in the process of industrialization, special attention should be paid to relying on scientific and technological progress and policy guidance to improve energy efficiency, seek clean utilization of energy, and actively advocate energy, environment and economy sustainable development.

2. Actively draw on advanced international experience to establish and improve our country’s energy security system

In order to ensure energy security, our country should, on the one hand, draw on advanced international experience, improve energy laws and regulations, and establish an energy security system. Market information statistics system, establish an early warning mechanism, energy reserve mechanism and energy crisis emergency mechanism for my country's energy security, actively advocate the diversification of energy supply in sources, varieties, trade, transportation and other methods, and improve the degree of marketization; on the other hand, we should strengthen Dialogue with major energy producing and consuming countries, expand the energy supply network, and realize the globalization of energy production, transportation, procurement, trade and utilization.

New energy is also called unconventional energy. Refers to various forms of energy other than traditional energy. Refers to energy that has just begun to be developed and utilized or is being actively researched and needs to be promoted, such as solar energy, geothermal energy, wind energy, ocean energy, biomass energy, and nuclear fusion energy.

It is estimated that the solar energy radiated to the earth every year is 1.78 billion kilowatts, of which 50 to 100 billion degrees can be developed and utilized. However, due to its scattered distribution, very little can be utilized at present. Geothermal energy resources refer to the total heat content of rocks and water within 5,000 meters of land. Among them, high-temperature geothermal energy resources above 150°C within a depth of 3 kilometers in the global land area amount to 1.4 million tons of standard coal. Currently, some countries have begun commercial development and utilization. The potential of wind energy in the world is about 350 billion kilowatts. Because wind power is intermittent and scattered, it is difficult to use it economically. If there are major improvements in energy transmission and storage technology in the future, wind power utilization will increase. Ocean energy includes tidal energy, wave energy, seawater temperature difference energy, etc. The theoretical reserves are very considerable. Due to technical limitations, it is still in the small-scale research stage. At present, because the utilization technology of new energy is not yet mature, it only accounts for a small part of the total energy required by the world, and it has great development prospects in the future.