Generator transmission and use of electrical energy. Production and use of electrical energy - Knowledge Hypermarket. Alternative Energy

All technological processes of any production are associated with energy consumption. The vast majority of energy resources are spent on their implementation.

The most important role in an industrial enterprise is played by electrical energy - the most versatile type of energy, which is the main source of mechanical energy.

The conversion of various types of energy into electrical energy takes place on power plants .

Power plants are enterprises or installations intended for the production of electricity. The fuel for power plants is natural resources - coal, peat, water, wind, sun, nuclear energy, etc.

Depending on the type of energy being converted, power plants can be divided into the following main types: thermal, nuclear, hydroelectric, pumped storage, gas turbine, as well as low-power local power plants - wind, solar, geothermal, marine tides, diesel, etc.

The bulk of electricity (up to 80%) is generated at thermal power plants (TPPs). The process of generating electrical energy at a thermal power plant consists in the sequential conversion of the energy of the burned fuel into the thermal energy of water vapor, which drives the turbine unit (a steam turbine connected to a generator). The mechanical energy of rotation is converted by the generator into electrical energy. The fuel for power plants is coal, peat, oil shale, natural gas, oil, fuel oil, wood waste.

With the economical operation of TPP, i.e. with simultaneous supply by the consumer of optimal amounts of electricity and heat, their efficiency reaches more than 70%. During the period when heat consumption is completely stopped (for example, during the non-heating season), the efficiency of the station decreases.

Nuclear power plants (NPPs) differ from conventional steam turbine plants in that nuclear power plants use the process of nuclear fission of uranium, plutonium, thorium, etc. as an energy source. As a result of the splitting of these materials in special devices - reactors, a huge amount of thermal energy is released.

Compared to thermal power plants, nuclear power plants consume a small amount of fuel. Such stations can be built anywhere, because. they are not related to the location of natural fuel reserves. In addition, the environment is not polluted by smoke, ash, dust and sulfur dioxide.

At hydroelectric power plants (HPPs), water energy is converted into electrical energy using hydraulic turbines and generators connected to them.

There are hydroelectric power stations of dam and diversion types. Dam hydroelectric power plants are used on flat rivers with low pressures, diversion hydroelectric power plants (with bypass channels) are used on mountain rivers with large slopes and with a small flow of water. It should be noted that the operation of the HPP depends on the water level determined by natural conditions.

The advantages of HPPs are their high efficiency and low cost of generated electricity. However, one should take into account the high cost of capital expenditures in the construction of hydroelectric power plants and the significant terms of their construction, which determines the long payback period.

A feature of the operation of power plants is that they must generate as much energy as it is required at the moment to cover the load of consumers, their own needs of stations and losses in networks. Therefore, the station equipment must always be ready for periodic changes in the load of consumers during the day or year.

Most power plants are combined in energy systems , each of which has the following requirements:

• Compliance of the power of generators and transformers with the maximum power of electricity consumers.
• Sufficient transmission capacity of power lines (TL).
• Ensuring uninterrupted power supply with high quality of energy.
• Economy, safety and ease of use.

To meet these requirements, power systems are equipped with special control rooms equipped with monitoring, control, communication facilities and special layouts for power plants, transmission lines and step-down substations. The control room receives the necessary data and information about the state of the technological process at power plants (water and fuel consumption, steam parameters, turbine rotation speed, etc.); about the operation of the system - which elements of the system (lines, transformers, generators, loads, boilers, steam pipelines) are currently disabled, which are in operation, in reserve, etc.; about the electrical parameters of the regime (voltages, currents, active and reactive powers, frequency, etc.).

The operation of power plants in the system makes it possible, due to a large number of generators operating in parallel, to increase the reliability of power supply to consumers, to fully load the most economical units of power plants, and to reduce the cost of electricity generation. In addition, the installed capacity of standby equipment in the power system is reduced; a higher quality of electricity supplied to consumers is ensured; the unit capacity of the units that can be installed in the system increases.

In Russia, as in many other countries, three-phase alternating current with a frequency of 50 Hz is used for the production and distribution of electricity (60 Hz in the USA and a number of other countries). Three-phase current networks and installations are more economical than single-phase alternating current installations, and also make it possible to widely use the most reliable, simple and cheap asynchronous electric motors as an electric drive.

Along with three-phase current, some branches of industry use direct current, which is obtained by rectifying alternating current (electrolysis in the chemical industry and non-ferrous metallurgy, electrified transport, etc.).

Electric energy generated at power plants must be transferred to the places of its consumption, primarily to large industrial centers of the country, which are many hundreds, and sometimes thousands of kilometers away from powerful power plants. But it is not enough to transfer electricity. It must be distributed among many different consumers - industrial enterprises, transport, residential buildings, etc. The transmission of electricity over long distances is carried out at high voltage (up to 500 kW or more), which ensures minimal electrical losses in power lines and results in greater savings in materials due to the reduction in wire cross-sections. Therefore, in the process of transmission and distribution of electrical energy, it is necessary to increase and decrease the voltage. This process is carried out by means of electromagnetic devices called transformers. The transformer is not an electrical machine, because his work is not related to the conversion of electrical energy into mechanical energy and vice versa; it converts only the voltage of electrical energy. The voltage increase is carried out using step-up transformers at power plants, and the decrease is carried out using step-down transformers at consumer substations.

An intermediate link for the transmission of electricity from transformer substations to electricity receivers are Electricity of the net .

A transformer substation is an electrical installation designed to convert and distribute electricity.

Substations can be closed or open, depending on the location of its main equipment. If the equipment is located in a building, then the substation is considered closed; if outdoors, then open.

Substation equipment can be assembled from separate elements of devices or from blocks supplied assembled for installation. Substations of block design are called complete.

The equipment of substations includes devices that carry out switching and protection of electrical circuits.

The main element of substations is a power transformer. Structurally, power transformers are made in such a way as to maximally remove the heat generated by them during operation from the windings and the core to the environment. To do this, for example, a core with windings is immersed in a tank with oil, the surface of the tank is made ribbed, with tubular radiators.

Complete transformer substations installed directly in industrial premises with a capacity of up to 1000 kVA can be equipped with dry transformers.

To increase the power factor of an electrical installation, static capacitors are installed at substations to compensate for the reactive power of the load.

The automatic system for monitoring and controlling the substation devices monitors the processes occurring in the load, in the power supply networks. It performs the functions of protecting the transformer and networks, disconnects the protected sections by means of a switch in emergency conditions, re-enables, automatically switches on the reserve.

Transformer substations of industrial enterprises are connected to the supply network in various ways, depending on the requirements for the reliability of uninterrupted power supply to consumers.

Typical schemes that provide uninterrupted power supply are radial, main or ring.

In radial schemes, lines supplying large electrical consumers depart from the switchboard of the transformer substation: motors, group distribution points, to which smaller receivers are attached. Radial circuits are used in compressor, pumping stations, shops of explosion and fire hazardous, dusty industries. They provide high reliability of power supply, make it possible to widely use automatic control and protection equipment, but require large expenditures for the construction of switchboards, cable and wire laying.

Trunk schemes are used when the load is evenly distributed over the workshop area, when it is not required to build a switchboard at the substation, which reduces the cost of the facility; prefabricated busbars can be used, which speeds up installation. At the same time, the movement of technological equipment does not require network alteration.

The disadvantage of the trunk scheme is the low reliability of power supply, since if the trunk is damaged, all electrical receivers connected to it are turned off. However, the installation of jumpers between the mains and the use of protection significantly increases the reliability of power supply at minimal cost for redundancy.

From substations, the low voltage current of industrial frequency is distributed to the workshops using cables, wires, busbars from the workshop switchgear to the electric drives of individual machines.

Breaks in the power supply of enterprises, even short-term, lead to violations of the technological process, damage to products, damage to equipment and irreparable losses. In some cases, a power outage can create an explosion and fire hazard in enterprises.

According to the rules for the installation of electrical installations, all receivers of electrical energy are divided into three categories according to the reliability of power supply:

• Power receivers for which an interruption in power supply is unacceptable, since it can lead to equipment damage, mass product defects, disruption of a complex technological process, disruption of the operation of critical elements of the urban economy and, ultimately, threaten people's lives.
• Energy receivers, the interruption in the power supply of which leads to non-fulfillment of the production plan, downtime of workers, mechanisms and industrial vehicles.
• Other receivers of electrical energy, for example, non-serial and auxiliary production workshops, warehouses.

The power supply to the first category electrical energy receivers must be ensured in any case and, in case of violation, is automatically restored. Therefore, such receivers must have two independent power sources, each of which can fully provide them with electricity.

Receivers of electricity of the second category may have a backup power supply, the connection of which is made by the staff on duty after a certain period of time after the failure of the main source.

For receivers of the third category, a backup power source, as a rule, is not provided.

The power supply of enterprises is divided into external and internal. External power supply is a system of networks and substations from the power source (power system or power plant) to the enterprise's transformer substation. In this case, energy transmission is carried out via cable or overhead lines with a rated voltage of 6, 10, 20, 35, 110 and 220 kV. The internal power supply includes the energy distribution system within the workshops of the enterprise and on its territory.

A voltage of 380 or 660 V is supplied to the power load (electric motors, electric furnaces), and 220 V to the lighting load. In order to reduce losses, it is advisable to connect motors with a power of 200 kW or more to a voltage of 6 or 10 kV.

The most common voltage at industrial enterprises is 380 V. The voltage of 660 V is widely introduced, which makes it possible to reduce energy losses and the consumption of non-ferrous metals in low-voltage networks, increase the range of workshop substations and the power of each transformer up to 2500 kVA. In some cases, at a voltage of 660 V, it is economically justified to use asynchronous motors with a power of up to 630 kW.

The distribution of electricity is carried out using electrical wiring - a set of wires and cables with related fasteners, supporting and protective structures.

Internal wiring is electrical wiring that is laid inside the building; external - outside it, along the outer walls of the building, under canopies, on supports. Depending on the laying method, internal wiring can be open if it is laid on the surface of walls, ceilings, etc., and hidden if it is laid in the structural elements of buildings.

Wiring can be laid with insulated wire or unarmoured cable up to 16 sq. mm. In places of possible mechanical impact, the electrical wiring is enclosed in steel pipes, sealed if the environment of the room is explosive, aggressive. On machine tools, printing machines, wiring is carried out in pipes, in metal sleeves, with a wire with PVC insulation, which does not collapse from exposure to machine oils. A large number of wires of the machine's electrical wire management system are placed in trays. Bus ducts are used to transmit electricity in workshops with a large number of production machines.

For the transmission and distribution of electricity, power cables in a rubber, lead sheath are widely used; unarmored and armored. Cables can be laid in cable channels, fixed on walls, in earthen trenches, embedded in walls.

Electricity, as a fundamental engine for the development of civilization, entered the life of mankind relatively recently. The active use of electricity began a little over a hundred years ago.

History of the world electric power industry

The electric power industry is a strategic branch of the economic system of any state. The history of the emergence and development of EE dates back to the end of the 19th century. The forerunner of the emergence of industrial power generation was the discovery of fundamental laws about the nature and properties of electric current.

The starting point, when the production and transmission of electricity arose, is considered to be 1892. It was then that the first power plant in New York was built under the leadership of Thomas Edison. The station became a source of electric current for street lighting lamps. This was the first experience of converting thermal energy from coal combustion into electricity.

Since then, the era of mass construction of thermal power plants (TPP) has begun, operating on solid fuel - thermal coal. With the development of the oil industry, huge reserves of fuel oil appeared, which were formed as a result of the processing of petroleum products. Technologies have been developed for obtaining a carrier of thermal energy (steam) from the combustion of fuel oil.

Since the thirties of the last century, hydroelectric power plants (HPPs) have become widespread. Enterprises began to use the energy of falling streams of water from rivers and reservoirs.

In the 1970s, the rapid construction of nuclear power plants (NPPs) began. At the same time, alternative sources of electricity began to be developed and introduced: these are wind turbines, solar panels, alkaline-acid geostations. Mini installations have appeared that use heat to generate electricity as a result of the chemical processes of decomposition of manure and household waste.

History of the Russian electric power industry

A powerful impetus to the development of electrical energy production was the adoption by the young state of the USSR of the GOELRO plan in 1920. It was decided to build 10 power plants with a total capacity of 640 thousand kW within 15 years. However, by 1935, 40 state district power plants (GRES) were put into operation. A powerful base for the industrialization of Russia and the union republics was created.

In the 1930s, mass construction of hydroelectric power plants (HPPs) began on the territory of the USSR. The rivers of Siberia were mastered. The famous Dneproges was built in Ukraine. In the postwar years, the state paid attention to the construction of hydroelectric power stations.

Important! The appearance in Russia of cheap electricity solved the problem of urban transport in large regional centers. Trams and trolleybuses have not only become an economic incentive for the use of electricity in transport, but also brought a significant reduction in the consumption of liquid fuels. A cheap energy resource led to the appearance of electric locomotives on the railways.

In the 1970s, as a result of the global energy crisis, there was a sharp increase in oil prices. A plan for the development of nuclear energy began to be implemented in Russia. Practically in all republics of the Soviet Union began to build nuclear power plants. Today's Russia has become the leader in this respect. Today, there are 21 nuclear power plants operating in the Russian Federation.

Main technological processes in the electric power industry

Electricity production in Russia is based on three pillars of the energy system. These are nuclear, thermal and hydropower.

Three types of electricity generation

Power Industry Industries

The list of industrial sources of electricity production consists of 4 energy sectors:

• atomic;
• thermal;
• hydropower;
• alternative.

Nuclear power

This branch of energy production is by far the most efficient way to generate electricity through a nuclear reaction. For this, purified uranium is used. The heart of the station is a nuclear reactor.

Heat sources are TVELs (fuel elements). They are thin long zirconium tubes in which uranium pellets are placed. They are combined into groups - TVS (fuel assembly). They load the reactor vessel, in the body of which pipes with water are placed. During the nuclear decay of uranium, heat is released, which heats the water in the primary circuit up to 3200.

The steam enters the blades of the turbines, which rotate the alternators. Electricity through transformers enters the general energy system.

Note! Remembering the tragedy of Chernobyl, scientists around the world are improving the safety system of nuclear power plants. Recent developments in the nuclear power industry provide almost 100% safety of nuclear power plants.

Thermal energy

Thermal power plants operate on the principle of burning natural fuels: coal, gas and fuel oil. The water passing through the pipelines through the boilers turns into steam and is subsequently fed to the blades of generator turbines.

Additional Information. For 4 years of operation of one group of fuel rods, such an amount of electricity is generated that the TPP will need to burn 730 natural gas tanks, 600 coal wagons or 900 oil tankers.

In addition, thermal power plants greatly worsen the ecological situation in the areas where they are located. The combustion products of fuels pollute the atmosphere. Only stations operating on gas turbine units meet the requirements of environmental cleanliness.

hydropower

Examples of the effective use of hydropower are the Aswan, Sayano-Shushenskaya hydroelectric power stations, etc. The most environmentally friendly power plants that use the kinetic energy of water movement do not produce any harmful emissions into the environment. However, the mass construction of hydraulic structures is limited by a combination of circumstances. This is the presence of a certain amount of natural water flow, a feature of the terrain, and much more.

alternative energy

The scientific and technological revolution does not stop for a minute. Every day brings innovations in obtaining electric current. Inquisitive minds are constantly on the lookout for new power generation technologies that act as alternatives to traditional ways of generating electricity.

Mention should be made of wind generators, tidal offshore stations and solar panels. Along with this, devices have appeared that generate electric current using the heat of decomposition of household waste, the waste products of cattle. There are devices that use the temperature difference of different soil layers, the alkaline and acidic environment of the soil at different levels. Alternative sources of electricity have one thing in common - this is the incompatibility of the generated amount of energy with the volumes of electricity that are received in traditional ways (nuclear power plants, thermal power plants and hydroelectric power plants).

Transmission and distribution of electrical energy

Regardless of the design of power plants, their energy is supplied to the country's unified energy system. The transmitted electricity is supplied to distribution substations, from there it reaches the consumers themselves. The transmission of electricity from producers is carried out by air through power lines. For short distances, the current passes in the cable, which is laid underground.

Electricity consumption

With the advent of new industrial facilities, the commissioning of residential complexes and civil buildings, electricity consumption is increasing every day. Almost every year, new power plants are put into operation in Russia, or existing enterprises are replenished with new power units.

Types of activities in the electric power industry

Electric companies are engaged in the uninterrupted delivery of electricity to each consumer. In the energy sector, the level of employment exceeds this indicator of some of the leading sectors of the national economy of the state.

Operational dispatch control

TAC plays a crucial role in the redistribution of energy flows in an environment of changing consumption levels. Dispatching services are aimed at transmitting electric current from the producer to the consumer in an accident-free mode. In the event of any accidents or failures in power lines, the ODUs perform the duties of the operational headquarters to quickly eliminate these shortcomings.

Energy supply

The tariffs for payment for electricity consumption include the cost of profits of energy companies. The correctness and timeliness of payment for consumed services is monitored by the service - Energosbyt. The financial support of the entire energy system of the country depends on it. Penalties are applied to non-payers, up to the disconnection of the consumer's power supply.

The energy system is the circulatory system of a single organism of the state. Electricity generation is a strategic sphere for the security of the existence and development of the country's economy.

Video

Types of power plants Thermal (TPP) - 50% Thermal (TPP) - 50% Hydroelectric power plants (HPP) % Hydroelectric power plants (HPP) % Nuclear (NPP) - 15% Nuclear (NPP) - 15% Alternative sources Alternative energy sources - 2 - 5% (solar energy, fusion energy, tidal energy, wind energy) energy - 2 - 5% (solar energy, fusion energy, tidal energy, wind energy)

Electric current generator Generator converts mechanical energy into electrical energy Generator converts mechanical energy into electrical energy The action of the generator is based on the phenomenon of electromagnetic induction The action of the generator is based on the phenomenon of electromagnetic induction

The frame with current is the main element of the generator. The rotating part is called the ROTOR (magnet). The rotating part is called the ROTOR (magnet). The fixed part is called the STATOR (frame) The fixed part is called the STATOR (frame) When the frame is rotated, penetrating the frame, the magnetic flux changes with time, as a result of which an induction current appears in the frame

Electricity transmission Power transmission lines (TL) are used to transmit electricity to consumers. When transmitting electricity over a distance, it is lost due to heating of the wires (the Joule-Lenz law). Ways to reduce heat loss: 1) Reducing the resistance of the wires, but increasing their diameter (heavy - difficult to hang, and expensive - copper). 2) Reducing the current strength by increasing the voltage.

The impact of thermal power plants on the environment Thermal power plants - lead to thermal air pollution by products of fuel combustion. Hydroelectric power stations - lead to flooding of vast territories that are being withdrawn from land use. Nuclear power plant - can lead to the release of radioactive substances.

The main stages of production, transmission and consumption of electricity 1. Mechanical energy is converted into electrical energy using generators at power plants. 1. Mechanical energy is converted into electrical energy using generators at power plants. 2. Electric voltage is increased to transmit electricity over long distances. 2. Electric voltage is increased to transmit electricity over long distances. 3. Electricity is transmitted at high voltage through high-voltage power lines. 3. Electricity is transmitted at high voltage through high-voltage power lines. 4. When distributing electricity to consumers, the voltage is reduced. 4. When distributing electricity to consumers, the voltage is reduced. 5. When electricity is consumed, it is converted into other types of energy - mechanical, light or internal. 5. When electricity is consumed, it is converted into other types of energy - mechanical, light or internal.

Lecture #3

Main sources of electricity

Lecture plan

1. Major electricity producers

2. Types of power plants

3. Autonomous sources of electricity

Main electricity producers

Power system (power system)- a set of power plants, electrical and heat networks, interconnected and connected by a common mode in the continuous process of production, conversion and distribution of electricity and heat with the overall control of this mode.

Features of the electric power industry as an industry are due to the specifics of its main product. Electricity is similar to a service in its properties: the time of its production coincides with the time of consumption. The electric power industry should be ready to generate, transmit and supply electricity at the time of the emergence of demand, including in peak volume, having the necessary reserve capacities and fuel reserves for this. The greater the maximum (even if short-term) value of demand, the greater the capacity must be to ensure the readiness to provide the service. (The situation will change if efficient technologies for storing electricity appear. So far, these are mainly batteries of various types, as well as pumped storage stations.)

The impossibility of storing electricity on an industrial scale predetermines the technological unity of the entire process of its production, transmission and consumption. This is probably the only branch in the modern economy where the continuity of production must be accompanied by the same continuous consumption. Due to this feature, the electric power industry has strict technical requirements for each stage of the technological cycle, including the frequency of electric current and voltage.

The fundamental feature of electrical energy as a product that distinguishes it from all other types of goods and services is that its consumer can affect the stability of the producer.

The needs of the economy and society for electrical energy significantly depend on weather factors, time of day, technological regimes of various production processes in consumer sectors, household characteristics, and even on the TV program. The difference between the maximum and minimum consumption levels determines the need for so-called reserve capacities, which are switched on only when the consumption level reaches a certain value.

Generation structure by fuel types: coal - 22%, natural gas - 41%, hydroelectric power stations - 16%, nuclear power plants - 12%, oil (fuel oil) - 5%, others - 4%.

The main electricity producers are:

Thermal power plants (TPP), where the thermal energy generated by the combustion of fossil fuels (coal, gas, fuel oil, peat, shale, etc.) is used to rotate turbines that drive an electric generator. The possibility of simultaneous production of heat and electricity has led to the spread in a number of countries of district heating at CHP;

Hydroelectric power plants (HPP), where the mechanical energy of the water flow is converted into electricity using hydraulic turbines that rotate electric generators;

Nuclear power plants (NPP), where the thermal energy obtained from the nuclear chain reaction of radioactive elements in the reactor is converted into electricity.

Thermal power plants (TPP), operating on fossil fuels (coal, fuel oil, gas, shale, peat) are today the main type of energy producers used in Russia.

The choice of location for thermal power plants is determined mainly by the presence of natural and fuel resources in a given region. Powerful thermal power plants are built, as a rule, in places where fuel resources are extracted or not far from large centers of the oil refining industry. Thermal power plants, which use local fuels (shale, peat, low-calorie and high-ash coals) as fuel, are trying to locate according to the need for electricity and, at the same time, taking into account the availability of certain types of fuel resources. Power plants operating on high-calorie fuel, the delivery of which to the place of use is economically feasible, are usually located taking into account consumer demand for electricity.

hydroelectric power plants are special structures erected in places where large rivers are blocked by a dam and using the energy of falling water to rotate the turbines of an electric generator. This method of generating electricity is the most environmentally friendly, since it does not burn any type of fuel and does not leave any harmful waste behind.

Nuclear power plants(NPPs) differ from thermal ones only in that if combustible fuel is used in TPPs to heat water and produce steam, then in NPPs, the source of water heating is the heat energy released during the nuclear reaction.

Currently, most of the electricity generated in the world is provided by thermal power plants, the capacity of which can be hundreds of thousands and millions of kilowatts.

For the joint and coordinated production of electricity, power plants of various types are combined into power systems. Combining power plants, as well as the power systems themselves, reduces the cost of electricity and guarantees uninterrupted power supply to the consumer. This is explained by the fact that the production and consumption of electricity occur simultaneously, and it is impossible to accumulate all the generated energy in any form. Therefore, power plants are required to have a certain operating capacity reserve, which is necessary in order to be able to satisfy the increased demand for electricity from the consumer at any time (for an increased load). And the value of consumption (demand for energy) can fluctuate sharply when the modes and operating conditions of consumers change.

In cities, in winter, for example, electricity consumption rises sharply, and in summer it decreases. In agriculture, on the contrary, electrical substations are more loaded in the summer, when seasonal field work is carried out. In addition, the maximum loads of power plants located in the east and west of the country usually do not coincide due to the difference in time. During the collective operation of power plants, they feed each other, which ensures their more uniform loading and increase in the efficiency of work.

At power plants that are not part of the power system, the use of powerful units for the transportation and conversion of electricity is not allowed. This is explained by the fact that the failure of such a node instantly paralyzes the work of industrial enterprises, de-energizes entire areas and threatens with an emergency shutdown of water supply systems, etc.

When combining power producers into power systems, there is no reason to refuse such powerful aggregate units, since the load of the failed section of the line will instantly be picked up by the remaining systems in working condition.

Along with the traditional method of generating electricity using power plants, they have become increasingly popular in recent years. alternative sources of electricity. Such sources include, for example, wind power generators, which convert the natural force of the wind into electric current.

Increasingly popular these days are solar panels, which, unlike an electric generator, use the principle of direct conversion of the energy of sunlight into electrical energy (photoelectric effect).

The three main types of power plants determine the types of energy resources used. They are usually divided into primary and secondary, renewable and non-renewable.

Primary energy carriers are raw materials in their natural form before any processing, such as coal, oil, natural gas and uranium ore. Colloquially, these materials are simply referred to as primary energy. This also includes solar radiation, wind, water resources. Secondary energy is a product of processing, “upgrading” of primary energy, such as gasoline, fuel oil, nuclear fuel.

Some types of resources can be restored relatively quickly in nature, they are called renewable: firewood, reeds, peat and other types of biofuels, the hydro potential of rivers. Resources that do not have this quality are called non-renewable: coal, crude oil, natural gas, oil shale, uranium ore. For the most part, they are minerals. The energy of the sun, wind, sea tides refers to inexhaustible renewable energy resources.

At present, coal is the most common type of technological fuel in the world electric power industry. This is due to the relative cheapness and widespread availability of this type of fuel. However, transportation of coal over long distances leads to high costs, which in many cases makes its use unprofitable. In the production of energy using coal, the level of emissions of pollutants into the atmosphere is high, which causes significant harm to the environment. In the last decades of the twentieth century. technologies have emerged that allow the use of coal to generate electricity with greater efficiency and less damage to the environment.

The expansion of the use of gas in the global power industry in recent years is due to a significant increase in its production, the emergence of highly efficient technologies for the production of electricity based on the use of this type of fuel, as well as the tightening of environmental protection policies.

Uranium is being used more and more. This fuel has tremendous efficiency compared to other raw energy sources. However, the use of radioactive substances is associated with the risk of large-scale environmental pollution in the event of an accident. In addition, the construction of nuclear power plants and the disposal of spent fuel are extremely capital intensive. The development of this type of energy is also complicated by the fact that so far few countries can provide training for scientific and technical specialists capable of developing technologies and ensuring the qualified operation of nuclear power plants.

Hydro resources remain of great importance in the structure of electricity sources, although their share has somewhat decreased over the past decades. The advantages of this source are its renewability and relative cheapness. But the construction of hydropower plants has an irreversible impact on the environment, since it usually requires the flooding of large areas during the creation of reservoirs. In addition, the uneven distribution of water resources on the planet and dependence on climatic conditions limit their hydropower potential.

A significant reduction in the use of oil and petroleum products for electricity generation over the past thirty years is explained both by the increase in the cost of this type of fuel, the high efficiency of its use in other industries, and the high cost of its transportation over long distances, as well as increased requirements for environmental safety.

There is growing attention to renewable energy sources. In particular, technologies for using solar and wind energy are being actively developed, the potential of which is huge. True, today the use of solar energy on an industrial scale in most cases is less efficient than traditional types of resources. As for wind energy, in developed countries (primarily under the influence of environmental movements), its use in the electric power industry has increased significantly. It is impossible not to mention also geothermal energy, which can be of great importance for some states or individual regions (Iceland, New Zealand, in Russia - for Kamchatka, the Stavropol and Krasnodar Territories, the Kaliningrad Region). The development of electricity generation based on renewable resources still requires government subsidies.

At the end of XX - beginning of XXI century. sharply increased interest in bioenergy resources. In some countries (for example, in Brazil), the production of electricity from biofuels made up a significant share in the energy mix. In the United States, a special biofuel subsidy program has been adopted. But there are also doubts about the prospects of this direction of the electric power industry. They relate primarily to the efficient use of such natural resources as land and water; for example, the conversion of large areas of arable land to biofuel production has contributed to a doubling of food grain prices.

Today we can no longer imagine our life without electricity. Almost all devices are powered by electricity, and even those that produce it.

There are several types of power plants - thermal power plants, hydroelectric power plants, nuclear power plants, BES, PES, etc., and sources from which we have learned to get the energy we need so much. At the beginning of the development of energy, the main raw material for production was coal. Now, a century later, we have learned how to produce electricity using other resources.

Electricity production in the world

The United States is the world's leading electricity producing country. In second place is China. Then the European Union, Russia, Japan. Nowadays, the production of electricity mainly occurs using oil, or rather, its fraction, referred to as fuel oil. But its use is gradually declining. As we live in an environmentally challenging time for the whole world, cleaner electricity generation is coming to replace it.

Wind energy was one of the first to be developed. Winds are constantly blowing everywhere and everywhere on earth. This means that the conditions for the development of wind energy are more than favorable. This is an environmentally friendly and easily accessible production.

Another alternative is solar power generation. Interest in this issue has grown significantly in recent years and continues to grow. Many minds are working to make getting electricity with the help of solar panels more profitable. Of course, in different electricity developed differently. And if solar stations for solar processing are suitable only for some southern regions, then, for example, this production can be used to its full potential. The same applies to the use of wind energy. In some countries, geothermal stations are still at the initial stage of development, which use the energy released from the earth in volcanic zones. In maintenance, such power plants are quite economical, but the construction of such facilities is expensive.

Electricity transmission

One of the most important tasks of the energy sector is the production and transmission of electricity to the consumer. And consumers are everywhere. Since electricity is generated only in certain places, there is a need to transmit it over long distances. For the transmission of electricity, power lines are mainly used - overhead power lines. It is known that when transmitting electricity over long distances, noticeable losses occur. At a considerable distance to the consumer, the transmission may become generally unprofitable. In order to maintain the transmitted power, it is necessary to increase the voltage in the power line. In this case, the greater the distance, the higher the voltage should be. For this purpose, transformers are installed at power plants to increase the voltage.

There is also a "closed" power transmission. It is a closed structure filled with electrically insulating gas. There are high voltage wires inside.

But even such a transfer of electricity is not always beneficial. In some cases, namely at very large distances, it is more expedient to transport fuel for production by rail: coal - in capacious wagons, and fuel oil - in tanks.

Looking ahead, since oil is quite volatile in terms of prices, and reserves are becoming much smaller, we will soon return to the predominant use of coal for electricity generation.