Power plants - types, characteristics of power plants

Why are power plants needed?

The power plant can easily be called one of the most important structures necessary to ensure the livelihoods of the population. Without electricity today, not a single settlement or enterprise can exist. Modern power plants are built far from densely populated areas, consist of a complex of buildings and installations, and are divided into various types and types, united by a common principle. It lies in the fact that they all operate from a system of generators that produce energy through shaft rotation.

Brief characteristics of thermal power plants

The schematic diagram involves the transfer of heat from the coolant to the turbine, as a result of which thermal energy is converted into electrical form. These types of power plants provide a cooling system for the waste coolant so that the temperature required for the recycle can be set. For this purpose, the heat from the waste coolant is used to heat water in the houses of a settlement located near the thermal power plant.

The main equipment of such stations is a boiler-steam generator, a cycle condenser, a generator, a circulation pump, and a turbine. The main types of power plants convert mechanical energy into electrical energy, supplying part of the steam to centralized heat mains.

Types of power plants

According to the method of generating energy, power plants are divided into:

• atomic. Energy is produced by nuclear reactors and a number of specialized installations and systems;
• thermal. The main one is external fuel, which, when burned, creates energy to turn the generator shaft;
• hydroelectric power stations. The main “force” is the natural energy of the rivers on which dams are installed;
• wind power plants. Depends on air masses;
• geothermal. They are powered by underwater thermal sources;
• sunny. Absorb and convert solar energy.

According to their purpose, power plants are divided into the following types:

• power. Necessary for power supply to large consumers, such as cities and factories;
• chargers. They are used to charge various accumulators and batteries, equipped with chargers, and the power plant must also include a DC electric drive;
• lighting Equipped with a complete set of spotlights and lamps, designed for lighting business facilities and construction sites;
• special. Used for welding and other types of work.

Power plants are also divided into:

• into variable and constant (according to the type of current);
• for diesel and gasoline (by engine type);
• for high-, medium- and low-power (in terms of power);
• for low and high voltage (voltage).

Energy

Energy is an area of ​​social production that covers energy resources, production, transformation, transmission and use of various types of energy. The energy sector of each state operates within the framework of the established corresponding energy systems.

Its goal is to ensure energy production by converting primary, natural energy into secondary, for example, electrical or thermal energy. In this case, energy production most often occurs in several stages:

• obtaining and concentration of energy resources, an example would be the extraction, processing and enrichment of nuclear fuel;
• transfer of resources to power plants, for example delivery of fuel oil to a thermal power plant;
• conversion of primary energy into secondary energy using power plants, for example, the chemical energy of coal into electrical and thermal energy;
• transfer of secondary energy to consumers, for example via power lines.

Energy as a science, in accordance with the nomenclature of specialties of scientific workers, approved by the Ministry of Education and Science of the Russian Federation, includes the following scientific specialties:

• Energy systems and complexes;
• Electric power plants and electrical power systems;
• Nuclear power plants;
• Industrial heat and power engineering;
• Power plants based on renewable energy;
• High voltage technology;
• Thermal power plants, their energy systems and units.

Types of power plants

Power plants come in various types, the most common of which are:

• Thermal
• Hydraulic
• Atomic

Thermal stations that produce energy are quick to construct and inexpensive compared to other types. This type of power plant is able to operate properly without seasonal fluctuations. Despite their undeniable advantages, various types of power plants have several disadvantages of their own. For example, thermal power plants operate on non-renewable resources, create waste, and their operating mode changes slowly, since it takes several days to heat up the boiler plant.

Hydraulic power plants are more economical and easier to operate. Maintenance of these stations does not require large numbers of personnel. Among other things, hydroelectric power plants have a long useful life, exceeding 100 years, as well as maneuverability when the load changes. The low cost of energy produced is one of the reasons for the widespread use of hydraulic power plants today. The problem with hydroelectric power plants is that their construction takes from 15 to 20 years and the construction process is complicated by the flooding of large areas of fertile land. In some cases, additional problems may arise with choosing a location for constructing an object.

Nuclear power plants operate on nuclear fuel and are most often located in places where electrical energy is required, but there are no other sources of raw materials. About 25 tons of fuel allow the station to operate for several years. The operation of nuclear power plants does not cause an increase in the greenhouse effect, and the energy generation process is carried out without polluting the environment.

Thermal power plants: types and principle of operation

The conversion of natural energy resources into electricity is carried out using special installations operating on various principles. Among them, the most widespread are thermal power plants that use liquid, solid and gaseous organic fuels. They generate more than 70% of the world's electricity and are located close to natural resource deposits. Many thermal power plants produce not only electricity, but also thermal energy.

Types of thermal power plants

A standard thermal power plant is a whole complex that includes various devices and equipment that convert fuel energy into electricity and heat.

Such installations differ in parameters and technical characteristics, according to which they are classified:

• In accordance with the types and purpose of the supplied electricity, thermal stations can be regional and industrial. Regional installations are known as GRES or IES and are designed to serve all consumers in the region. Power plants that produce heat are called CHP plants. The power of regional stations exceeds 1 million kW. Industrial power plants are designed to supply electricity and heat to specific enterprises and industrial complexes. Their power is significantly less than that of state district power plants and is installed in accordance with the needs of a particular facility.
• All types of thermal power plants operate on different energy sources. First of all, these are ordinary organic resources used by most thermal power plants and petroleum products. The most widespread are coal, natural gas, and fuel oil. The most advanced installations operate on nuclear fuel and are called nuclear power plants - NPPs.
• Power plants that convert heat energy into electricity can be steam turbine, gas turbine, or mixed steam-gas design.
• The technological diagram of steam pipelines of thermal power plants can be different. In block designs, thermal power plants use identical power plants or power units. In them, steam from the boiler is supplied only to its own turbine and, after condensation, it returns to its boiler. Most of the state district power plants (CHPPs) and thermal power plants were built according to this scheme. Another option involves the use of cross connections, when steam from the boilers is supplied to a common manifold - a steam pipeline, which ensures the operation of the entire steam turbines of the station.
• According to the initial pressure parameters, thermal power plants can be with critical and supercritical pressure. In the first case, Russian standards for TPP-CHP are 8.8-12.8 MPa or 90-130 atmospheres. The second option has higher parameters of 23.5 MPa or 240 atmospheres. Such designs use intermediate superheating and a block circuit.

Operating principle of a thermal power plant

The basic principle of operation of a thermal power plant is to produce thermal energy from fossil fuels, which is subsequently used to generate electric current.

The concepts of thermal power plant and combined heat and power plant differ significantly from each other. The first installations are so-called pure power plants that produce only electric current. Each of them is also known as a condensing power plant - CES. CHP stands for combined heat and power plant and is a type of thermal power plant. These installations not only generate electricity, but are also thermal, that is, they provide heat to heating and hot water supply systems. This combined use requires special steam turbines with back pressure or an intermediate steam extraction system.

Despite the variety of designs, all thermal power plants operate according to a common scheme. The boiler is constantly supplied with fuel in the form of coal, gas, peat, fuel oil or oil shale. Many power plants use pre-cooked coal dust. Along with the fuel, heated air is supplied, which acts as an oxidizer.

During the combustion of fuel, heat is created that heats the water in the steam boiler. Saturated steam is formed and supplied to the steam turbine through a steam line. Next, thermal energy becomes mechanical.

The shaft and other moving parts of the turbine are interconnected and form a single whole. A jet of steam at high pressure and high temperature exits the nozzles and impacts the turbine blades. Fixed to the disk, they begin to rotate and drive a shaft connected to the generator. As a result of rotation, mechanical energy is converted into electrical current.

After passing through the steam turbine, the steam reduces its temperature and pressure. It then enters the condenser and is pumped through tubes cooled by water. Here the steam finally turns into water and enters the deaerator to remove dissolved gases. Purified water is supplied to the boiler plant through a heater using a pump.

Coal-fired thermal power plant

Coal has long been one of the main sources of energy in people's daily life and production activities. The wide distribution of this type of fuel became possible due to its availability. In many deposits it is located a few meters from the surface of the earth and can be mined using a cheaper open-pit method. In addition, coal does not require any special storage conditions and is stored in ordinary piles near the site.

Industrial use of coal began at the end of the 18th century. Later, when railway transport appeared, coal became the source of motive power for steam locomotives. It was later used in the first thermal power plants built at the end of the 19th century. Many thermal power plants currently operate on coal.

At the very first power plants, coal was burned by placing it on grates. Fuel loading and slag removal were performed manually. Gradually, these processes were mechanized and coal fell onto the grates from the upper bunker. The grate was set in motion and the waste slag was poured into a special receiver.

Modern thermal power plants no longer use lump coal. Instead, coal dust produced in crushers or mills is loaded into the boilers. Fuel is supplied to the burners by compressed air. Once in the firebox, coal dust mixed with air begins to burn, releasing a large amount of heat.

Gas thermal power plants

Second only to coal in importance is natural gas, used by many thermal power plants. This type of fuel has undoubted advantages. Harmful emissions that poison the atmosphere are significantly lower than when burning coal. After combustion, no by-products remain in the form of slag or ash.

The operation of thermal power plants using gas becomes much easier, since in this case the preparation of coal dust is not required. The gas does not require any special preparation and is immediately ready for use. Gas thermal power plants are considered more maneuverable, which is important in situations with changing loads.

The efficiency and efficiency of gas thermal power plants increased significantly when they switched to operating mode with the cycle of combined cycle plants. The fuel is burned not in a boiler, but in a gas turbine. Such installations are intended only for gas and cannot operate on coal dust.

Other types of fuel for thermal power plants

In addition to traditional fuels, thermal power plants also use other energy sources in their work. One such energy resource is fuel oil, which was used in many power plants in the second half of the 20th century.

In modern conditions, the price of petroleum products has increased significantly, so fuel oil has ceased to be the main fuel. It is partially used by coal-fired power plants for kindling. The performance qualities of fuel oil are similar to those of natural gas, however, when it is burned, large quantities of sulfur oxide are released, which pollutes the environment.

In the 20th century, some thermal power plants operated on peat. Currently, this resource is practically not used due to low efficiency compared to gas and coal. Diesel fuel installations are used in small facilities where significant amounts of electricity are not required. Basically, they are intended for remote areas located at a considerable distance from centralized power supply networks.

Thermal power plant efficiency

The main indicator of any thermal power plant is its efficiency. For example, for coal-fired thermal power plants there is a thermal efficiency determined by the amount of coal required to generate 1 kWh of electricity. If at the beginning of the 20s of the last century this figure was 15.4 kg, then in the 60s it dropped to 3.95 kg. Subsequently, coal consumption again increased slightly to 4.6 kg.

The reason for this increase was gas scrubbers, dust and ash collectors, due to which the coal-fired power plant reduced its power output by 10%. Many stations use cleaner coal, which has also led to increased fuel consumption.

The percentage expression of the thermal efficiency of a thermal power plant is no more than 36%, which is associated with high heat losses caused by exhaust gases during combustion. Nuclear power plants with low temperatures and pressure have even lower thermal efficiency - 32%. The highest rate is for gas turbine plants equipped with waste heat boilers and additional steam turbines. The efficiency of power plants with such equipment exceeds 40%. This indicator completely depends on the operating temperatures and steam pressure.

Modern steam turbine power plants use intermediate superheating of steam. After it has partially worked in the turbine, it is taken out at an intermediate point for subsequent reheating to the original temperature. The reheat system can consist of two or more stages, which contributes to a significant increase in thermal efficiency.

The most powerful thermal power plants

Currently, the Tuoketuo thermal power plant, located in China in the province of Inner Mongolia, is rightfully considered the leader in thermal energy. Until recently, it was only the third in the world, inferior in power to thermal power plants located in Taichung and Surgut. As a result of the reconstruction, two power units of 660 MW each were added in 2022, after which the total capacity of the station reached 6,720 megawatts. After this, Surgutskaya GRES began to occupy 3rd place in the world and 1st in Russia.

In the Russian Energy System, the share of thermal power plants is about 70%, and the total number in physical figures is 358 units. The largest thermal power plants are located near large mineral deposits used as fuel. Installations that use fuel oil are tied to large oil refineries.

The largest Russian thermal power plant is Surgut, with a capacity of 5,600 MW. On the map, the geographical location of the object is determined at approximately the same distance from Nefteyugansk and Khanty-Mansiysk.

Construction of the facility began in 1979, and in 1985 the 1st power unit was put into operation. Then, within 3 years, all remaining power units with a capacity of 800 MW came into operation. The station operates on associated gas generated in the areas of developed gas fields. Such gas must be utilized, but it has become an energy resource. To date, 2 more power units of 400 MW each have been built, which made it possible to bring the station to its designed capacity.

It should be noted that there is another large Russian state district power station - Reftinskaya. It runs on hard coal and has a capacity of 3,800 megawatts. The facility is located approximately 100 km from Yekaterinburg. Construction was carried out from 1963 to 1980, during the entire period the power units were commissioned in stages.

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Basics of power plant operation

Regardless of what kind of power plants there are , they mostly use the energy of rotation of the generator shaft. The purpose of the generator is that it:

1. Must ensure long-term stable parallel operation with power systems of various capacities, as well as operation on an autonomous load
2. Undergoes instantaneous load shedding and resurgence comparable to its rated power
3. Performs a protective function due to the presence of special devices
4. Starts the engine that ensures the operation of the station

Power plants are the most optimal way to generate energy due to a number of factors. To date, there are no similar methods that can produce electricity on such a large scale.

Power systems

Energy systems are a set of energy resources of all types, methods and means of their production, transformation, distribution and use, ensuring the supply of consumers with all types of energy.

What is included in the energy system

Energy systems include:

• electrical power system;
• oil and gas supply system;
• coal industry system;
• nuclear energy;
• non-traditional energy.

Typically, all these systems are combined on a national scale into a single energy system, and on the scale of several regions into unified energy systems. The integration of individual energy supply systems into a single system is also called the intersectoral fuel and energy complex; it is primarily due to the interchangeability of various types of energy and energy resources

Often, an energy system in a narrower sense is understood as a set of power plants, electrical and thermal networks that are interconnected and connected by common modes of continuous production processes for the conversion, transmission and distribution of electrical and thermal energy, which allows for centralized management of such a system.

In the modern world, consumers are supplied with electricity from power plants, which may be located close to consumers or may be located considerable distances away from them. In both cases, the transmission of electricity is carried out through power lines. However, if consumers are remote from the power plant, transmission must be carried out at a higher voltage, and step-up and step-down substations must be built between them. Through these substations, using electrical lines, power plants are connected to each other for parallel operation on a common load, also through heating points using heat pipelines, only at much shorter distances, thermal power plants and boiler houses are connected to each other.

The combination of all these elements is called an energy system; with such a combination, significant technical and economic advantages arise:

• significant reduction in the cost of electricity and heat;
• significant increase in the reliability of electricity and heat supply to consumers;
• increasing the efficiency of operation of various types of power plants;
• reduction of the required reserve capacity of power plants.

Characteristics of industrial power plants

Industrial plants are power plants included in manufacturing enterprises. Their main purpose is to supply energy to the relevant enterprises and surrounding areas. The fundamental features of industrial stations include:

Based on the type of energy produced, industrial stations are divided into the following groups:

• Producing only electrical energy
• Supplying consumers with electricity and heat energy
• Additionally supplying consumers with compressed air

Depending on the type of engine installed, power plants with steam or gas turbines, internal combustion engines, and locomotives are distinguished.

In addition to the power and type of station, there are a number of other parameters and characteristics. The ability to connect individual consumer devices depends on the phase pattern of the station. There are single-phase and three-phase autonomous power plants. In a three-phase installation, the power is distributed evenly between all phases.

An equally important characteristic is the frequency of the current generated by the installation. In accordance with the standards, this figure is 50 Hz in Russia. In other countries, including Japan, Canada and the United States, this setting may be as high as 60 Hz. The maximum strength of the generated current of power plants is determined in amperes. It is not allowed to connect to the power installation a load whose amperage consumption exceeds the maximum current transmission capability of the unit.

Taking into account all the characteristics of power plants, it will be possible to ensure their maximum performance and stable operation over a long period of time. Depending on the presence or absence of specific technical characteristics, it is necessary to regulate the load on the station.

Main types

The classification of power plants is primarily carried out by type of energy carrier. These include coal, natural gas, river water, nuclear fuel, diesel fuel, gasoline, etc. List of main stations:

1. TPP - abbreviation: thermal power plant. It uses natural fuel to operate, and it can be condensing (CPP) or heating (CHP).
2. A hydroelectric power station is a hydraulic power plant that operates using river water falling from a height. There is a variety of it - pumped storage power plant (pumped storage).
3. NPPs are nuclear power plants whose energy source is nuclear fuel.
4. DPPs are stationary or mobile power plants running on diesel fuel. Typically these are low-power stations that are used in construction and the private sector where there are no power lines.

There are also solar, wind, tidal and geothermal power sources, which are poorly used in our country. They have a number of natural disadvantages and represent alternative forms of electricity generation.

Thermal and hydraulic

Thermal power plants in Russia generate about 70% of all electricity. For their operation, fuel oil, coal, gas, and in some regions, peat and shale are used. In addition to electrical energy, thermal power plants produce thermal energy.

One of the main elements of the station is a turbine, which rotates due to the generated steam. The advantage of thermal power plants is that its equipment can be placed almost anywhere where natural energy resources are available. In addition, their work is practically not affected by natural factors.

But the fuel used is not renewable, that is, its resources may run out, and the equipment itself pollutes the environment. In Russia, thermal stations are not equipped with effective systems for removing harmful and toxic substances.

Gas equipment is considered more environmentally friendly, but the pipes leading to it also harm the environment. Stations located in the central region of the country operate on natural gas and fuel oil, and in the eastern regions - on coal. Therefore, they are located closer to natural fuel deposits.

In terms of their importance, hydraulic stations are in second place after thermal power plants. Their main difference is the use of water energy, which is a renewable resource. If you look at the map of Russia, you will notice that the most powerful hydroelectric power stations are located in Siberia on the Yenisei and Angara. List of major power plants:

1. Sayano-Shushenskaya - has a capacity of 6.4 thousand MW.
2. Krasnoyarsk - 6 thousand MW.
3. Bratskaya - 4.5 thousand MW.
4. Ust-Ilimskaya - 3.84 thousand MW.

The operating principle of the installations is quite simple . The falling water sets turbines in motion, which turn generators, and electricity begins to be generated. The cost of electricity produced by hydroelectric power plants is considered the cheapest, and it is 5-6 times less than from thermal power plants. In addition, fewer employees are required to operate the hydraulic station.

The big difference is the startup time of the installation. If for hydroelectric power plants this parameter is 3-5 minutes, then for thermal power plants it will last several hours. On the other hand, a hydraulic installation operates at full capacity only when the water level is high.

Nowadays, much attention is paid to the construction of pumped storage stations, which differ from traditional installations in the ability to move the same amount of water between the lower and upper basins. At night, when there is excess electricity, water is supplied from bottom to top, and during the day - vice versa.

Nuclear and diesel

In terms of the amount of energy produced, nuclear power plants are in third place. Their share in the Russian energy sector is only 10%. In the United States the figure is 20%, and the highest rate is in France at over 75%.

After the disaster at the Chernobyl nuclear power plant, the program for the construction and development of nuclear power plants was reduced. The most famous objects in Russia:

• Leningradsky;
• Kursk;
• Smolensky;
• Beloyarsky and others.

Nowadays, the most popular are nuclear thermal power plants, the purpose of which is to produce electrical energy and heat. A station of this type operates in the village of Bilibino in Chukotka. In addition, one of the latest trends is the creation of nuclear heat supply plants, in which nuclear energy is converted into thermal energy.

Such equipment operates successfully in Nizhny Novgorod and Voronezh. When properly operated, a nuclear power plant is the most environmentally friendly installation, namely:

• minor emissions into the atmosphere;
• oxygen is practically not absorbed;
• no greenhouse effect is created.

If we consider the principle of operation of a nuclear power plant, we should take into account the catastrophic consequences after accidents. Spent energy also requires special burial in nuclear repositories.

Mobile diesel power plants have become an integral part for supplying electricity to remote areas and construction sites. In addition, they are often used as emergency or backup sources.

The main element of the equipment is a generator, which rotates from an internal combustion engine. Stationary installations can have a power of up to 5 thousand kW, and mobile ones - no more than 1 thousand kW.

One of their advantages is their compact size, so they can be placed in small spaces. The disadvantages include dependence on the availability of fuel, methods of its delivery and storage.

Diesel power plants

Diesel power plants are a very practical and effective solution to the problem of autonomous power supply to various types of objects.

Main advantages:

• low cost of generated electricity;
• quick payback;
• long service life and durability.

Despite the fact that the cost of a diesel power plant is much higher than a gasoline one, it is much cheaper to operate, which compensates for the difference in price. Also, diesel power plants, due to their greater engine life, can operate much longer than gasoline power plants. Due to these circumstances, diesel power plants have found their application as sources of constant or emergency power supply in continuous production. It is impossible not to note the high reliability and durability of diesel power plants.

Diesel power plants can be operated in the harshest weather conditions - at air temperatures from -50 to +50 *C. However, it should be remembered that the diesel engine is somewhat capricious in winter conditions, and different fuels are used at different times of the year.

Diesel power plants are also susceptible to temperature changes (for example, sharp frosts). The point here is this. Summer diesel fuel, which can be used without problems in the warm season, is not suitable for use in winter.

Due to the cold, paraffin precipitates in the fuel itself, which clogs the fuel lines. Therefore, winter diesel fuel is additionally processed and paraffin is removed. Naturally, it becomes more expensive than the summer one.

However, with all this, it is necessary to point out the obvious advantage of a diesel power plant - diesel fuel is not volatile, like gasoline vapors or gas. This provides the diesel engine with a kind of explosion protection, which is especially valuable for diesel power plants, often used as auxiliary units in the elimination of various disasters and accidents. Even a significant leak of diesel fuel does not pose a danger to others and workers.

Gasoline power plants

Gasoline power plants have their advantages:

• relatively low cost of equipment compared to other types;
• compactness;
• easy start-up at low temperatures;
• low noise level of the power plant;
• ease of operation.

The main purpose of gasoline power plants is as a source of power for a short time (up to 7-8 hours). Today, manufacturers of gasoline electric generators produce two types of power plants - with two-stroke and four-stroke engines. Engines of the first type are installed on low-power gasoline generators and mobile power stations.

Such installations are highly mobile and can be used in almost any conditions, so they can be called universal. More powerful stationary gas generators are equipped with four-stroke engines, providing higher power and a longer service life.

Gas power plants

Main advantages of gas power plants:

• the service life of gas power plants is 25% higher than that of gasoline and diesel analogues;
• the gas generator is easy to maintain and install, and is highly reliable;
• cheaper in terms of consumables;
• clean, smokeless and less harmful exhaust;
• acceptable noise level.

Main purpose: use of a gas power plant as a source of backup or main power supply for an indefinite time interval (if connected to a gas pipeline).
The main advantage of a gas generator is that it is possible to simultaneously generate electricity and use the heat that is obtained as a result of the operation of a gas power plant. This heat can be used, for example, to heat buildings and other needs.

Gas-powered generators are divided depending on the design of the power units driving the generator. These can be gas piston engines or gas turbines.

Before purchasing a power plant, it is recommended to clearly assess the planned load on the device - this will be all devices operating using electric current (power calculation). Their rated power and phase connection are important. These are two main factors that will influence the initial selection of the generator you need.

The choice of power plant depends on several factors. First of all, this is, of course, determining the type of its engine, the generator itself and the phase pattern, and then the subsequent selection of the model according to certain characteristics and indicators.

Advantages of nuclear power plants over thermal power plants

The advantages and disadvantages of nuclear power plants depend on what type of electricity generation we compare nuclear energy with. Since the main competitors of nuclear power plants are thermal power plants and hydroelectric power stations, let us compare the advantages and disadvantages of nuclear power plants in relation to these types of energy production.

TPPs, that is, thermal power plants, are of two types:

1. Condensing or briefly CESs serve only to produce electricity. By the way, their other name comes from the Soviet past, IESs are also called GRESs - short for “state district power plant”. 2. Combined heat and power plants or combined heat and power plants only allow producing not only electrical, but also thermal energy. Taking, for example, a residential building, it is clear that CES will only provide electricity to the apartments, and CHP will also provide heating in addition.

As a rule, thermal power plants operate on cheap organic fuel - coal or coal dust and fuel oil. The most popular energy resources today are coal, oil and gas. According to experts, the world's coal reserves will last for another 270 years, oil – for 50 years, gas – for 70. Even a schoolchild understands that 50-year reserves are very small and must be protected, and not burned in furnaces every day.

Nuclear power plants solve the problem of shortage of organic fuel. The advantage of nuclear power plants is the elimination of fossil fuels, thereby preserving endangered gas, coal and oil. Instead, nuclear power plants use uranium. World uranium reserves are estimated at 6,306,300 tons. No one is counting how many years it will last, because... There are a lot of reserves, uranium consumption is quite small, and there is no need to think about its disappearance yet. In extreme cases, if uranium reserves are suddenly carried away by aliens or they evaporate on their own, plutonium and thorium can be used as nuclear fuel. Converting them into nuclear fuel is still expensive and difficult, but it is possible.

The advantages of nuclear power plants over thermal power plants include a reduction in the amount of harmful emissions into the atmosphere.

What is released into the atmosphere during the operation of thermal power plants and thermal power plants and how dangerous it is:

1. Sulfur dioxide or sulfur dioxide is a dangerous gas that is harmful to plants. If ingested in large quantities, it causes coughing and suffocation. When combined with water, sulfur dioxide turns into sulfurous acid. It is thanks to sulfur dioxide emissions that there is a risk of acid rain, which is dangerous for nature and humans. 2. Nitrogen oxides are dangerous for the respiratory system of humans and animals, irritating the respiratory tract. 3. Benapyrene is dangerous because it tends to accumulate in the human body. Long-term exposure may cause malignant tumors.

The total annual emissions of thermal power plants per 1000 MW of installed capacity are 13 thousand tons per year at gas and 165 thousand tons at pulverized coal thermal stations. A thermal power plant with a capacity of 1000 MW per year consumes 8 million tons of oxygen to oxidize fuel; the advantages of nuclear power plants are that in nuclear energy oxygen is not consumed in principle.

The above emissions are also not typical for nuclear power plants. The advantage of nuclear power plants is that emissions of harmful substances into the atmosphere at nuclear power plants are negligible and, compared to emissions from thermal power plants, are harmless.

The advantages of nuclear power plants over thermal power plants are low fuel transportation costs. Coal and gas are extremely expensive to transport to factories, while the uranium needed for nuclear reactions can be placed in one small truck.

Non-traditional types of electricity production

(wind power plants, solar power plants, geothermal power plants, etc.)

In recent years, numerous publications have appeared on non-traditional renewable energy sources. Estimates of the possibilities of their widespread use range from enthusiastic to moderately pessimistic. The Greens call for the complete replacement of all traditional fuel and nuclear energy with the use of unconventional renewable sources.

Non-traditional renewable energy sources usually include:

• sunny,
• wind and geothermal energy,
• the energy of sea tides and waves,
• biomass (plants, various types of organic waste),
• low-potential environmental energy.

This category also includes small hydroelectric power plants (with a capacity of up to 30 MW with a single unit power of no more than 10 MW), which differ from traditional - larger - hydroelectric power plants only in scale.

These energy sources have both positive and negative properties. The positive ones include the ubiquity of most of their species and environmental cleanliness. Operating costs for the use of non-traditional sources do not contain a fuel component, since the energy of these sources is, as it were, free.

Negative qualities are the low flux density (power density) and time variability of most energy sources. The first circumstance forces the creation of large areas of power installations that “intercept” the flow of used energy (receiving surfaces of solar installations, the area of ​​a wind wheel, extended dams of tidal power plants, etc.). This leads to high material consumption of such devices, and consequently to an increase in specific capital investments compared to traditional power plants. True, increased capital investments are subsequently recouped due to low operating costs, but at the initial stage they seriously “hit the pockets” of those who want to use unconventional renewable energy sources.

More troublesome is caused by the time variability of such energy sources as solar radiation, wind, tides, runoff of small rivers, and environmental heat. If, for example, the change in tidal energy is strictly cyclical, then the process of solar energy receipt, although generally natural, nevertheless contains a significant element of randomness associated with weather conditions. Wind energy is even more variable and unpredictable. But geothermal installations, with a constant flow of geothermal fluid in the wells, guarantee constant energy production (electrical or thermal). In addition, plants using biomass can provide stable energy production if they are supplied with the required amount of this “energy raw material”.

Speaking about the production of electricity, it should be noted that it is a very specific type of product that must be consumed at the same moment as it is produced. It cannot be sent “to a warehouse” like coal, oil or any other product or commodity, since the fundamental scientific and technical problem of storing electricity in large quantities has not yet been solved, and there is no reason to believe that it will be solved in the foreseeable future.

For small autonomous wind and solar power plants, it is possible and advisable to use electrochemical batteries, but when producing electricity from these unregulated sources on an industrial scale, difficulties arise due to the impossibility of constantly matching electricity production with its consumption (with the load schedule). A sufficiently powerful energy system, which also includes wind power plants (WPP) or wind power plants (WPP) and solar power plants (SPP), can compensate for changes in the power of these stations. However, in this case (in order to avoid changes in the parameters of the power system, primarily frequency), the share of unregulated power plants should not exceed, according to preliminary estimates, 10...15% (in terms of power).

As for the “free” nature of most types of non-traditional renewable energy sources, this factor is offset by significant costs for the purchase of appropriate equipment. As a result, a certain paradox arises in that it is mainly rich countries that are able to use free energy. At the same time, developing countries that do not have a modern energy infrastructure, i.e., a developed centralized energy supply network, are most interested in exploiting non-traditional renewable energy sources. For them, the creation of an autonomous energy supply through the use of non-traditional sources could be a solution to the problem, but due to their poverty they do not have the funds to purchase sufficient quantities of appropriate equipment. Rich countries do not experience energy hunger and show interest in alternative energy mainly for environmental reasons, energy saving and diversification of energy sources.

In general, the use of non-traditional renewable energy sources in the world has acquired significant proportions and a steady upward trend. In some countries, the share of non-traditional sources in the energy balance is a few percent. According to various forecast estimates, of which there is currently no shortage, this share in 2010–2015. in many states will reach or exceed 10%. Various types of non-traditional renewable energy sources are at different stages of development. Paradoxically, it is the most volatile and unstable type of energy – wind – that has received the greatest use. The total global installed capacity of large wind turbines and wind farms, according to various estimates, ranges from 10 to 20 GW. The apparent paradox is explained by the fact that specific capital investments in wind turbines are lower than when using most other types of renewable energy sources.

Not only the total power of wind turbines is growing, but also their unit power, which has exceeded 1 MW.

A new industry has emerged in many countries – wind power engineering. Apparently, wind energy will retain its leading position in the near future. The world leaders in the use of wind energy are the USA, Germany, the Netherlands, Denmark, and India. The second place in terms of application volume is occupied by geothermal energy. The total global capacity of geothermal power plants is at least 6 GW. They are quite competitive compared to traditional fuel power plants. However, geothermal power plants are geographically tied to steam-hydrothermal deposits or to thermal anomalies, which are by no means ubiquitous, which limits the scope of application of geothermal installations. Along with geothermal power plants, geothermal heat supply systems have become widespread.

Next comes solar energy. It is used mainly to produce low-grade heat for domestic hot water supply and district heating. The predominant type of equipment here is the so-called flat solar collectors. Their global production, according to our estimates, is at least 2 million m2 per year, and the production of low-grade heat from solar energy reaches 5 × 106 Gcal.

The conversion of solar energy into electricity is increasingly underway. Two methods are used here - thermodynamic and photoelectric, with the latter leading by a wide margin. Thus, the total global capacity of autonomous photovoltaic installations has reached 500 MW. Mention should be made here of the Thousand Roofs project implemented in Germany, where 2,250 houses were equipped with photovoltaic installations. In this case, the role of a backup source is played by the electrical network, from which the energy shortage is compensated. In case of excess energy, it, in turn, is transferred to the network. It is curious that during the implementation of this project, up to 70% of the cost of installations was paid from the federal and state budgets. The United States has adopted an even more ambitious “Million Solar Roofs” program, designed to run until 2010. Federal budget expenditures for its implementation will amount to $6.3 billion. However, for now, the bulk of off-grid photovoltaic installations are coming through international financial support to developing countries where they are most needed. The direction associated with the use of low-grade heat from the environment (water, soil, air) using heat pump units (HPU) has received significant development. In HPP, when one unit of electrical energy is consumed, 3–4 equivalent units of thermal energy are produced, therefore, their use is several times more profitable than direct electrical heating. They also successfully compete with fuel installations.

The use of biomass energy is developing no less intensively. The latter can be converted into technically convenient types of fuel or used to produce energy through thermochemical (combustion, pyrolysis, gasification) and (or) biological conversion. In this case, wood and other plant and organic wastes are used, including city waste, livestock and poultry waste. With biological conversion, the end products are biogas and high-quality environmentally friendly fertilizers. This direction is important not only from the point of view of energy production. Perhaps, it is even more valuable from an environmental point of view, since it solves the problem of recycling hazardous waste.

In recent years, there has been a revival of interest in the creation and use of small hydropower plants. They are becoming increasingly widespread in many countries on a new, higher technical basis, associated, in particular, with the full automation of their work with remote control.

The practical application of tidal energy is much less developed. There is only one large tidal power plant (TPP) in the world with a capacity of 240 MW (Rance, France). The use of sea wave energy is even less developed.

In Russia, their practical application lags significantly behind the scale achieved in other countries. And this is despite such favorable prerequisites as practically unlimited resources of non-traditional renewable energy sources, and a fairly high scientific, technical and industrial potential in this area.

Disadvantages of nuclear power plants over thermal power plants

1. The disadvantages of nuclear power plants over thermal power plants are, first of all, the presence of radioactive waste. They try to recycle radioactive waste at nuclear plants as much as possible, but they cannot dispose of it at all. The final waste at modern nuclear power plants is processed into glass and stored in special storage facilities. Whether they will ever be used is still unknown. 2. The disadvantages of nuclear power plants are their low efficiency compared to thermal power plants. Since processes in thermal power plants occur at higher temperatures, they are more productive. It is still difficult to achieve this in nuclear power plants, because zirconium alloys, which indirectly participate in nuclear reactions, cannot withstand extremely high temperatures. 3. The general problem of heat and nuclear power plants stands apart. The disadvantage of nuclear power plants and thermal power plants is thermal pollution of the atmosphere. What does it mean? When generating nuclear energy, a large amount of thermal energy is released, which is released into the environment. Thermal pollution of the atmosphere is a problem of today, it entails many problems such as the creation of heat islands, changes in microclimate and, ultimately, global warming.

Modern nuclear power plants already solve the problem of thermal pollution and use their own artificial pools or cooling towers (special cooling towers for cooling large volumes of hot water) to cool water.

How does a nuclear power plant work?

Any station is a closed area far from a residential area. There are several buildings on its territory. The most important structure is the reactor building, next to it is the turbine room from which the reactor is controlled, and the safety building.

A nuclear power plant scheme is impossible without a nuclear reactor. An atomic (nuclear) reactor is a nuclear power plant device that is designed to organize a chain reaction of neutron fission with the obligatory release of energy during this process. But what is the operating principle of a nuclear power plant?

The entire reactor installation is housed in the reactor building, a large concrete tower that hides the reactor and will contain all the products of the nuclear reaction in the event of an accident. This large tower is called containment, hermetic shell or containment zone.

The hermetic zone in new reactors has 2 thick concrete walls - shells. The outer shell, 80 cm thick, protects the containment zone from external influences.

The inner shell, 1 meter 20 cm thick, has special steel cables that increase the strength of concrete almost three times and will prevent the structure from crumbling. On the inside, it is lined with a thin sheet of special steel, which is designed to serve as additional protection for the containment and, in the event of an accident, not to release the contents of the reactor outside the containment zone.

This design of the nuclear power plant allows it to withstand an airplane crash weighing up to 200 tons, a magnitude 8 earthquake, a tornado and a tsunami.

The first sealed shell was built at the American Connecticut Yankee nuclear power plant in 1968.

The total height of the containment zone is 50-60 meters.

Advantages and disadvantages of nuclear power plants over hydroelectric power plants

The advantages and disadvantages of nuclear power plants over hydroelectric power plants are mainly related to the dependence of hydroelectric power stations on natural resources. More about this...

1. The advantage of nuclear power plants over hydroelectric power plants is the theoretical possibility of building new nuclear power plants, while most rivers and reservoirs capable of working for the benefit of hydroelectric power plants are already occupied. That is, the opening of new hydroelectric power stations is difficult due to the lack of necessary places. 2. The next advantage of nuclear power plants over hydroelectric power plants is their indirect dependence on natural resources. Hydroelectric power plants directly depend on the natural reservoir, nuclear power plants only indirectly on uranium mining, everything else is provided by the people themselves and their inventions.

The disadvantages of nuclear power plants compared to water stations are insignificant - the resources that a nuclear power plant uses for a nuclear reaction, and specifically uranium fuel, are not renewable. While the amount of water, the main renewable resource of a hydroelectric power station, will not change in any way from the operation of a hydroelectric power station, and uranium itself cannot be restored in nature.

Electric power industry

Electric power is a subsystem of the energy sector that includes the production of electricity at power plants and its delivery to consumers via power transmission lines. Its central elements are power plants, which are usually classified according to the type of primary energy used and the type of converters used for this. It should be noted that the predominance of one or another type of power plant in a particular state depends primarily on the availability of appropriate resources.

Electric power industry is usually divided into traditional and non-traditional.

Traditional electric power

A characteristic feature of traditional electric power is its long-standing and good development; it has undergone long-term testing in a variety of operating conditions. The main share of electricity throughout the world is obtained from traditional power plants; their unit electrical power very often exceeds 1000 MW. Traditional electric power industry is divided into several areas.

Thermal energy (thermal power engineering)

In this industry, electricity is produced at thermal power plants (TPPs), using chemical energy from fossil fuels.

Thermal power plants are divided into:

• Steam turbine power plants, in which energy is converted using a steam turbine unit;
• Gas turbine power plants, in which energy is converted using a gas turbine unit;
• Combined-cycle power plants, in which energy is converted using a combined-cycle plant.

Thermal energy on a global scale predominates among traditional types; 39% of the world's electricity is generated from oil, 27% from coal, 24% from gas, that is, only 90% of the total output of all power plants in the world. The energy of such countries as Poland and South Africa is almost entirely based on the use of coal, and the Netherlands - gas. The share of thermal power engineering in China, Australia, and Mexico is very large.

Hydropower

In this industry, electricity is produced at hydroelectric power plants (HPPs), using the energy of water flow for this purpose.

Hydroelectric power plants predominate in a number of countries - in Norway and Brazil, all electricity generation occurs on them. The list of countries in which the share of hydroelectric power generation exceeds 70% includes several dozen.

Nuclear energy

An industry in which electricity is produced at nuclear power plants (NPPs), using the energy of a controlled nuclear chain reaction, most often from uranium and plutonium.

France is the leader in terms of the share of nuclear power plants in electricity generation, about 80%. It also prevails in Belgium, the Republic of Korea and some other countries. The world leaders in the production of electricity from nuclear power plants are the USA, France and Japan.

Non-traditional power engineering (Alternative energy)

Most areas of non-traditional electric power are based on completely traditional principles, but the primary energy in them is either local sources, such as wind, geothermal, or sources that are under development, such as fuel cells or sources that can be used in the future, such as thermonuclear energy. The characteristic features of non-traditional energy are their environmental friendliness, extremely high capital construction costs (for example, for a solar power plant with a capacity of 1000 MW it is necessary to cover an area of ​​about 4 km² with very expensive mirrors) and low unit power.

Directions of non-traditional energy:

• Small hydroelectric power plants
• Wind energy
• Geothermal energy
• Solar energy
• Bioenergy
• Fuel cell installations
• Hydrogen energy
• Thermonuclear energy.

We can also highlight a concept that is important due to its widespread use - small-scale energy; this term is not currently generally accepted; along with it, the terms local energy, distributed energy, autonomous energy, etc. are used. Most often, power plants with a capacity of up to 30 MW with units are called this way. unit capacity up to 10 MW. These include both the environmentally friendly types of energy listed above and small power plants using fossil fuels, such as diesel power plants (among small power plants they are the vast majority, for example in Russia - approximately 96%), gas piston power plants, low-power gas turbine units using diesel and gas fuel.

Electricity of the net

An electrical network is a set of substations, switchgears and power lines connecting them, designed for the transmission and distribution of electrical energy. The electrical network provides the possibility of issuing power from power plants, transmitting it over a distance, converting electricity parameters (voltage, current) at substations and distributing it throughout the territory up to direct power consumers.

Electrical networks of modern energy systems are multi-stage, that is, electricity undergoes a large number of transformations on the way from electricity sources to its consumers. Also, modern electrical networks are characterized by multi-mode, which means the variety of loads of network elements on a daily and annual basis, as well as the abundance of modes that arise when various network elements are brought into scheduled repairs and during their emergency shutdowns. These and other characteristic features of modern electrical networks make their structures and configurations very complex and diverse.

Non-traditional sources of electricity

Non-traditional sources are represented by geothermal power plants (Fig. 1), operating on thermal energy coming from the bowels of the earth. The deeper from the earth's surface, the higher the temperature of this layer. In Russia, such installations were built in Kamchatka and the Kuril Islands.

There are designs of tidal power plants (Fig. 2), which operate from the energy created by the ebb and flow of tides at the narrowest point of an artificial bay, cut off from the sea. An example is the experimental Kislogubskaya TPP, built on the Kola Peninsula.

The classification of power plants includes solar and wind alternative installations (Fig. 3). All types of such systems provide electricity to small enterprises and industries and are used in the private sector to meet domestic needs. Basically, these are areas and places where there is no centralized power supply and there is no possibility of connecting to ordinary power lines.

Energy in Russia

The main types of power plants in our country: thermal, nuclear, hydroelectric power plants. More than half of the energy is generated by thermal power plants. They are built in areas where fuel is extracted, or in areas where energy is consumed. It is advisable to build hydroelectric power stations on mountain full-flowing rivers, which is why such stations appeared on the Angara and Yenisei.

These types of power plants in Russia also exist on the Volga. Hydroelectric power stations account for about 67% of the country's electrical energy.

Different types of nuclear power plants in Russia are located in the western part of the country, where there is increased energy consumption.

Alternative energy sources

These include all other methods of generating energy, the most common of which are: solar power plant, wind power plant and tidal power plant.

Solar power plants

They use the energy of the sun, there are several ways to obtain it, we will look at this in another article.

Wind power station

- a power plant that uses wind energy.

Tidal power plants

generally speaking about themselves.

Solar panels

When discussing what types of power plants exist in our country, we cannot ignore alternative installations for generating electrical energy.

The sun is not only a source of heat and light; thanks to it, many other types of energy are used (for example, oil, water, coal, wind).

The use of solar panels in the northern regions of the country is not as profitable as in warmer areas. And yet, many residents of the Russian Federation are trying to use alternative energy. To make the right decision about the effective use of an alternative energy source, you need to think about the cost of solar panels on the domestic market. It is difficult to name the exact price of one kilowatt generated by a solar collector.

Today in Russia, 1 watt of electrical energy obtained from solar panels has a much higher price than the same amount of energy obtained from traditional sources.

Power is a key parameter of a household power plant

The main technical parameter of any power plant is power. Manufacturers of household power plants indicate a maximum power level that is achieved only in short periods of time. To calculate the actual power level, it is necessary to additionally take into account the power factor. Actual performance is usually less than the maximum and is determined in kilowatts.

Household power plants of different types have the following power:

• Gasoline: 15-20 kW
• Diesel: up to 3000 kW

Generators with different outputs differ from each other in size, weight, cost and other parameters. When choosing a household power plant, you should consider all the characteristics together, including the efficiency indicated in the documentation provided for the unit.

Energy fuel

Since most of the traditional power plants and heating sources produce energy from non-renewable resources, the issues of extraction, processing and delivery of fuel are extremely important in the energy sector. Traditional energy uses two fundamentally different types of fuel.

Organic fuel

Depending on the state of aggregation, organic fuel is divided into gaseous, liquid and solid, each of them in turn is divided into natural and artificial. The share of such fuel in the global energy balance was about 65% in 2000, of which 39% was coal, 16% natural gas, 9% liquid fuel (2000). In 2010, according to BP, the share of fossil organic fuels was 87%, including: oil 33.6%, coal 29.6%, gas 23.8%. The same according to “Renewable21” 80.6%, not counting traditional biomass 8.5%.

Gaseous

Natural fuel is natural gas, artificial:

• Producer gas;
• Coke gas;
• Blast gas;
• Petroleum distillation products;
• Underground gasification gas;
• Synthesis gas.

Liquid

The natural fuel is oil; the products of its distillation are called artificial:

• Petrol;
• Kerosene;
• Solar oil;
• Fuel oil.

Solid

Natural fuels are:

Fossil fuel:

• Peat;
• Brown coal;
• Coal;
• Anthracite;
• Oil shale;

Vegetable fuel:

• Firewood;
• Wood waste;
• Fuel briquettes;
• Fuel pellets.

Artificial solid fuels are:

• Charcoal;
• Coke and semi-coke;
• Carbon briquettes;
• Coal processing waste.

Nuclear fuel

The main and fundamental difference between nuclear power plants and thermal power plants is the use of nuclear fuel instead of organic fuel.

Nuclear fuel is obtained from natural uranium, which is mined:

• In mines (France, Niger, South Africa);
• In open pits (Australia, Namibia);
• Using underground leaching (USA, Canada, Russia).

For use in nuclear power plants, uranium must be enriched, so after mining it is sent to an enrichment plant, after processing where 90% of the by-product depleted uranium is sent for storage, and 10% is enriched to a few percent (3-5% for power reactors). Enriched uranium dioxide is sent to a special plant, where cylindrical pellets are made from it, which are placed in sealed zirconium tubes almost 4 m long, fuel rods (fuel elements). For ease of use, several hundred fuel rods are combined into fuel assemblies and fuel assemblies.