The use of nuclear energy The use of nuclear energy in the modern world is so important that if we woke up tomorrow and the energy of the nuclear reaction disappeared, the world, as we know it, would probably cease to exist. Peaceful use of sources ...

03 08 2016

Permanent magnets, although they have a supply of energy, give it up very reluctantly, so there is no need to specifically call this energy. However, an electric current creates extended, strong magnetic fields around itself. As soon as the current turns off, the magnetic field ...

01 08 2016

The most commonly encountered in everyday life is mechanical energy. This is the energy of direct interaction and movement of physical bodies and their parts. In the framework of Mechanics (Physics section), mechanical energy is divided into potential (for those at rest ...

27 07 2016

Light energy is familiar to all people of all times from birth. Since ancient times, such sources of light energy as the Sun, Moon and Stars, bonfire, torch, chemiluminescent animals and plants are known. Currently, the Sun continues to be the main and ...

25 07 2016

Is it cold or hot in our world? At first glance, the matter of the universe is not so hot. We breathe cool air, drink cold water, ride on ice, make snowballs. The black night sky does not warm us. To keep warm, you have to light bonfires and heat stoves. Meanwhile, ...

23 07 2016

Chemical energy is known to every modern person and is widely used in all fields of activity. It has been known to Mankind since the earliest times and has always been used both in everyday life and in production. The most common devices using ...

20 07 2016

In many cases, electric and magnetic energies are closely related to each other, each of them can be considered as the “back side” of the other. Alternating currents are created by alternating electric fields and form alternating magnetic fields around themselves. During...

20 06 2016

The energy carried by the wave can be huge. An example of this is the World Ocean. When a calm, affectionately licking shore, the surface turns into a storm, sea waves can destroy ships, throw huge rocks ashore, splash water into highly raised reservoirs, ...

Types of energy - types of energy known to mankind

The concept of "energy" is defined as a measure of various forms of motion of matter and as a measure of the transition of matter from one form to another. Accordingly, the types and types of energy are distinguished by the forms of motion of matter. The little man deals with various types of energy. In fact, the whole technological process is the conversion of some types of energy into others. In the process of passing the technological path, energy is repeatedly converted from one type to another, which leads to a decrease in its useful amount due to losses and dispersion in the environment.

Types of Energy Known Today

• Mechanical
• Electric
• Chemical
• Thermal
• Light (Radiant)
• Nuclear (Atomic)
• Thermonuclear (Thermonuclear Fusion)

  In addition, we also know other types of energy whose names have not physical, but descriptive meaning, such as wind energy, or geothermal energy. In such cases, the physical form of the nature of the energy is replaced by the name of its source. Therefore, it is correct to speak more about mechanical wind energy, wind flow energy, or thermal energy of geothermal sources. Otherwise, the amount of pseudo energies can be generated indefinitely by inventing garbage energy, hydrogen energy, mental energy, or life energy, and the energy of the hands. Combining the word "energy" with specific objects, we deprive this bundle of physical meaning. It is impossible to measure the amount of psychic energy, or will energy. All that remains is a hint that the object has some energy, and which is unknown to us. It turns out that the text or speech is littered with a word that does not carry a semantic load, because every object carries energy and it makes no sense to mention it. And by analogy with the energy of thought, a mass of thought, the length, width and height of thought, as well as its density, should appear. In short, such revolutions are obvious evidence of the stupidity and illiteracy of the author, or orator.

Physical concepts related to the definition of the word "energy"

But back to the real physical concepts associated with the definition of the word "energy". The above types of energy are known to man and have been used by him throughout the history of civilization. The only exception is the energy of atomic decay, obtained only at the beginning of the 20th century. So, we still use mechanical energy while riding a bicycle, using a pendulum clock, raising and lowering loads by a crane. Since ancient times, electrical energy has been familiar to us in the form of lightning and static electricity. However, this type of energy was widely used only from the 19th century, when the Voltaic pole was invented - a direct current battery and. However, even in ancient times, people knew and used this type of energy, although not universally. Ancient Egyptian jewelry and cult objects are known, the coating of which could be done only by electrolysis. - Perhaps the most common and widely used form of energy, both in antiquity and today. Bonfire, coals, burner, matches and many other objects associated with combustion are based on the energy of the chemical interaction of organic matter and oxygen. Today, high-tech "combustion" is carried out in and in and. However, devices such as turbines and internal combustion engines between raw materials (chemical energy) and the final product (electric energy) have a bad intermediary -. Unfortunately, the efficiency heat engines is small, and the limitations are imposed not by material, but by theory. For the limit is 40%. On the basis of chemical interactions, chemical energy, both human bodies and all animals act. Eating plants, we get from them the energy of chemical bonds formed through the absorption of solar energy. That is, indirectly, a person also feeds on solar energy, as all living things on Earth feed on it. The sun is that energy, without which life on our planet would not exist. Almost all types and types of energy, except atomic and thermonuclear, can be considered secondary, in relation to radiant solar energy. The mechanical energy of the tides, as well as the thermal geothermal sources, are also not related to solar radiation.

Thermonuclear energy underlies the work of our central luminary - the Sun

And this means that solar energy, in turn, is a product of thermonuclear fusion energy released in the bowels of the sun. Thus, the vast majority of the types of energy that we use on Earth have their primary progenitor in the form of thermonuclear fusion energy. Nuclear or atomic energy is the only type of energy that falls outside the limits of the "standard" natural energy turnover. Before the appearance of man, nature did not know (with rare exceptions) the processes of mass point decay of atomic nuclei with the release of huge energy. The exception is the African natural "nuclear reactor" - a uranium ore deposit, where there are reactions of atomic decay with the heating of surrounding rocks. However, in nature, atomic decay lasts millions of years, because the half-lives of uranium and plutonium are very long. And although many other atoms are also subject to atomic decay, in addition to uranium and plutonium, in general, these processes do not cause significant changes in the surrounding matter per unit time. A man made his changes to the energy balance of the planet, exploding bombs, building nuclear power plants, burning oil, gas and coal. Of course, similar processes took place before humans, but they were stretched for millions of years. Meteorites fell, forests burned, carbon dioxide emissions from swamps and strata of the world's oceans occurred, uranium decayed. But slowly - in small volumes per unit time.

Alternative sources

Today, alternative forms of energy and alternative ones are actively developing. However, in these words themselves already lies an erroneous attitude to the word "energy". Calling energy sources “alternative”, we contrast them with “traditional” sources - coal, oil and gas. And that is understandable. But when we say “alternative type of energy” we are talking nonsense because different types of energy exist outside our desires. And it is not clear what alternative wind energy is, because it simply is. Or what is alternative solar and thermonuclear energy of our luminary. In any case, we use it, and it is strange to call it alternative, since there are no alternatives for it. In the next thousand years, we will not go anywhere from the use of solar energy, since the entire ecosystem of the planet is based on it. The words “non-traditional forms of energy”, “renewable forms of energy”, or “environmentally friendly forms of energy” look similarly strange. What kind of energy is traditional? How can one or another type of energy be renewed? And how to check energy for environmental cleanliness? “Traditionality”, “renewability” and “environmental friendliness” are more rationally and correctly attributed to. Then everything will immediately become clear and understandable. And then, having ordered the cause-effect relationships, you can start the search. Unconventional types of energy sources can be easily found by studying nature and the surrounding world. Here you have manure for heating, hay, and a generator that uses muscular strength.

Renewable energy sources should be sought only in the environment of natural processes.

  There are not so many similar processes and all of them are connected with the movement of matter on the planet - earth, water, air, as well as with the activity of living organisms. Although, strictly speaking, there are no renewable energy sources, since our main "battery" - the Sun - has a limited service life. And for the search for environmentally friendly sources, it is necessary to clearly define the criteria for environmental friendliness, because, in fact, any human intervention in the energy balance of the planet causes damage to the environment. Strictly speaking, there can be no environmentally friendly energy sources, because in any case they will affect the environment. We can only minimize this effect, or compensate for it. Moreover, any compensatory effects should be carried out within the framework of the global analytical forecasting model.

Types, methods of obtaining, converting and using energy. Energy and its types. Purpose and use

Energy and its types. Purpose and use

Energy plays a crucial role in the development of human civilization. Energy consumption and the accumulation of Information have approximately the same character of change over time. There is a close relationship between energy consumption and output.

According to the ideas of physical science, energy is the ability of a body or system of bodies to do work. There are various classifications of types and forms of energy. Let us call those species that people most often encounter in their daily lives: mechanical, electrical, electromagnetic, and internal. Internal energy includes thermal, chemical and intranuclear (atomic). The internal form of energy is due to the potential energy of interaction of the particles that make up the body, or the kinetic energy of their random motion.

If energy is the result of a change in the state of motion of material points or bodies, then it is called kinetic; it includes mechanical energy of the motion of bodies, thermal energy due to the movement of molecules.

If energy is the result of a change in the relative position of parts of a given system or its position in relation to other bodies, then it is called potential; it includes the energy of masses attracted by the law of universal gravitation, the energy of the position of homogeneous particles, for example, the energy of an elastic deformed body, chemical energy.

The main source of energy is the sun. Under the influence of its rays, the chlorophyll of plants decomposes the carbon dioxide absorbed from the air into oxygen and carbon; the latter accumulates in plants. Coal, underground gas, peat, shale and firewood represent the reserves of radiant, solar energy, extracted by chlorophyll in the form of chemical energy of coal and hydrocarbons. The energy of water is also obtained due to solar energy, which evaporates water and raises steam to high layers of the atmosphere. The wind used in wind turbines occurs as a result of different heating of the sun by the sun in different places. Huge reserves of energy are contained in the nuclei of atoms of chemical elements.

In the International SI system of units, the joule is adopted as the unit of energy. If the calculations are related to heat, biological, electrical, and many other types of energy, then calories (cal) or kilocalories (kcal) are used as the unit of energy.

1 cal \u003d 4.18 J.

To measure electric energy, use such a unit as Watts (Wh, kWh, MWh).

1 watts h \u003d 3.6 MJ or 1 J \u003d 1 W. from.

A unit such as kg is used to measure mechanical energy. m

1 kg. m \u003d 9.8 J.

The energy that is contained in natural sources (energy) and can be converted into electrical, mechanical, chemical, is called primary.

The traditional types of primary energy, or energy resources, include: fossil fuels (coal, oil, gas, etc.), river hydropower, and nuclear fuel (uranium, thorium, etc.).

The energy received by a person after the conversion of primary energy at special plants installations is called secondary (electrical energy, energy of steam, hot water, etc.).

Currently, work is underway on the use of non-traditional, renewable energy sources: solar, wind, tides, sea waves, the warmth of the earth. These sources, in addition to being renewable, belong to “clean” forms of energy, since their use does not lead to environmental pollution.

In fig. 10.1.1 shows the classification of primary energy. The traditional types of energy, at all times widely used by man, and non-traditional, relatively little used until recently due to the lack of economical ways of their industrial conversion, but especially relevant today due to their high environmental friendliness, are distinguished.

Fig. 10.1.1. Primary Energy Classification Scheme

In the classification scheme, non-renewable and renewable forms of energy are indicated by white and gray rectangles, respectively.

The required type of energy consumption and supply to consumers occurs in the process of energy production, in which five stages can be distinguished: 1. Production and concentration of energy resources: extraction and enrichment of fuel, concentration of water pressure using hydraulic structures, etc.

2. Transfer of energy resources to energy conversion plants; it is carried out by land or water transport or by pumping water, oil, gas, etc. through pipelines.

3. The conversion of primary energy into secondary, having the most convenient form for distribution and consumption under the given conditions (usually into electric and thermal energy).

4. Transmission and distribution of converted energy.

5. Energy consumption, carried out both in the form in which it is delivered to the consumer, and in the converted one.

If the total energy of the primary energy used is taken as 100%, then the useful energy used will be only 35–40%, the rest is lost, most of it in the form of heat.

Electric power advantage

From distant historical times, the development of civilization and technological progress are directly related to the quantity and quality of energy resources used. A little more than half of the total energy consumed is used in the form of heat for technical needs, heating, cooking, the remaining part in the form of mechanical, primarily in transport installations, and electrical energy. Moreover, the share of electric energy is growing every year (Fig. 10.2.1).

Fig. 10.2.1. The dynamics of electricity consumption

Electric energy is the most convenient form of energy and can rightfully be considered the basis of modern civilization. The vast majority of technical means of mechanization and automation of production processes (equipment, devices, computers), the replacement of human labor by machine in everyday life, have an electrical basis.

Why is demand for electric energy so rapidly growing, what is its advantage?

Its widespread use is due to the following factors: the possibility of generating electricity in large quantities near deposits and water sources;

1. the ability to transport over long distances with relatively small losses;
2. the possibility of transforming electricity into other types of energy: mechanical, chemical, thermal, light;
3. lack of environmental pollution;
4. the possibility of applying fundamentally new progressive technological processes based on electricity with a high degree of automation.

All these are different types of energy. All processes occurring in nature require energy. In any process, one form of energy is converted into another. Food products - potatoes, bread, etc. - these are energy storages. Almost all the energy used on Earth is received from the sun. transfers to Earth as much energy as 100 million powerful power plants would produce.

Types of energy

Energy exists in many different forms. In addition to heat, light and sound energy, there is also chemical energy, kinetic and potential. A light bulb emits thermal and light energy. The energy of sound is transmitted through waves. The waves cause the eardrums to vibrate and therefore we hear sounds. Chemical energy is released during chemical reactions. Food products, fuel (coal, oil, gasoline), as well as batteries are storages of chemical energy. Food products are stores of chemical energy released within the body.

Moving bodies possess kinetic energy, i.e. energy of movement. The faster the body moves, the greater its kinetic energy. Losing speed, the body loses kinetic energy. Hitting a stationary object, a moving body transfers part of its kinetic energy to it and sets it in motion. Part of the energy received from food, animals turn into kinetic.

Potential energy is possessed by bodies located in a force field, for example, in gravitational or magnetic. Elastic or elastic bodies (with the ability to stretch) have the potential energy of tension or elasticity. The pendulum has the maximum potential energy when it is at the top point. When deployed, the spring releases its potential energy and makes the wheels in the watch rotate. Plants receive energy from the Sun and produce nutrients - create reserves of chemical energy.

Energy conversion

The law of conservation of energy says that energy is not created from nothing and is not lost without a trace. With all processes occurring in nature, one type of energy is converted into another. The chemical energy of the flashlight's batteries turns into electrical energy. In a light bulb, electrical energy is converted into heat and light. We gave an example of this “energy chain” to show you how one type of energy is transformed into another.

Coal is the compressed remains of a plant that lived many years ago. Once they received energy from the sun. Coal is a chemical energy reserve. When coal burns, its chemical energy ceases to heat. Thermal energy heats the water and it evaporates. Steam rotates the turbine. thereby producing kinetic energy - the energy of motion. A generator converts kinetic energy into electrical energy. A variety of devices - lamps, televisions, heaters, tape recorders - consume electricity and translate into sound, light and heat.

The final results in many energy conversion processes are light and heat. Although the energy does not disappear, it goes into space, and it is difficult to catch and use.

Solar power

The energy of the sun reaches the earth in the form of electromagnetic waves. Only in this way can energy be transmitted through outer space. It can be used to create electricity using photocells or to heat water in solar collectors. The collector panel absorbs the thermal energy of the sun. The figure shows a collector panel in section. The black panel absorbs the thermal energy coming from the Sun, and heats up in the pipes. This is the structure of the roof of a house heated by the Sun. Solar energy is transmitted to water used for domestic needs and heating. Excessive heat enters the energy storage. Energy is saved through chemical reactions.

Energetic resources

We need energy for lighting and heating homes, for cooking, so that factories can work and cars move. This energy is generated during the combustion of fuel. There are other ways to get energy - for example, it produces hydro power plants. For cooking and heating homes, almost half of the world's population burns firewood, manure or coal.

Wood, coal, oil and natural gas are called non-renewable resourcessince they are used only once. The sun, wind, water are renewable energy, since they themselves do not disappear in the production of energy. In his activity, man uses fossil resources for energy extraction - 77%, wood - 11%, renewable energy - 5% and nuclear energy - 3%. We call coal, oil and natural gas fossil fuels, since we extract them from the bowels. They were formed from the remains of plants and animals. Almost 20% of the energy we use is produced from coal. When burning fuel, carbon dioxide and other gases get into it. This is partly the reason for such phenomena as acid rain and the greenhouse effect. Only about 5 percent of energy comes from renewable sources. This is the energy of the sun, water and wind. Another renewable source of energy is the gas produced by decay. When organic matter rots, gases are released, in particular methane. It mainly consists of natural gas, which is used to heat homes and heat water. For several millennia, people have been using wind power to move sailing ships and rotate windmills. Wind can also produce electricity and pump water.

Energy and power units

To measure the amount of energy, a special unit is used - the joule (J). One thousand joules amount to one kilojoule (kJ). An ordinary apple (about 100 g) contains 150 kJ of chemical energy. 100 g of chocolate contains 2335 kJ. Power is the amount of energy used per unit of time. Power is measured in watts (W). One watt is equal to one joule per second. The more energy a particular mechanism produces over a given time, the greater its power. A 60 W bulb uses 60 J per second, and a 100 W bulb uses 100 J per second.

Efficiency

Any mechanism consumes energy of one kind (for example, electric) and turns it into energy of another kind. The efficiency (efficiency) of the mechanism is the greater, the greater part of the energy consumed is converted into the necessary energy. Efficiency of almost all cars is low. On average, a car converts only 15% of the chemical energy of gasoline into kinetic energy. All other energy is converted into heat. The efficiency of fluorescent lamps is higher than the efficiency of ordinary light bulbs, since in fluorescent lamps more electricity is converted into light and less is spent on heat production.