Providing the population with heat and electricity is one of the main tasks of the state. In addition, without generating electricity it is impossible to imagine a developed manufacturing and processing industry, without which the country's economy cannot exist in principle.
One way to solve the problem of energy shortages is the construction of thermal power plants. The interpretation of this term is quite simple: this is the so-called cogeneration plant, which is one of the most common varieties of thermal power plants. In our country, they are very common, because they work on organic fossil fuels (coal), the characteristics of which make very modest requirements.
Features
That's what a CHP plant is. Decoding of the concept is already familiar to you. But what features does this variety of power plants have? After all, it is no coincidence that they are singled out in a separate category !?
The fact is that they produce not only electricity, but also heat, which is supplied to consumers in the form of hot water and steam. It should be noted that electricity is a by-product, since the steam that is supplied to the heating systems first rotates the generator turbines. The combination of two enterprises (boiler house and power plant) is good because it is possible to significantly reduce fuel consumption.
However, this also leads to a rather insignificant “distribution area” of thermal power plants. The interpretation is simple: since not only electricity is supplied from the station, which can be transported for thousands of kilometers with minimal losses, but also the heated coolant, they can not be located at a considerable distance from the village. It is not surprising that almost all thermal power plants were built in close proximity to the cities whose inhabitants they heat and illuminate.
Ecological importance
Due to the fact that during the construction of such a power plant it is possible to get rid of many old city boiler houses, which play an extremely negative role in the ecological condition of the district (a huge amount of soot), the air purity in the city can sometimes be increased by an order of magnitude. In addition, the new CHPPs eliminate waste debris in urban landfills.
The latest cleaning equipment allows you to effectively clean the emissions, and the energy efficiency of such a solution is extremely high. So, the energy release from burning a ton of oil is identical to the volume that is released when disposing of two tons of plastic. And this "good" will last for decades to come!
Most often, the construction of a thermal power plant involves the use of fossil fuels, as we discussed above. However, in recent years it is planned to create nuclear power plants that will be mounted in the conditions of inaccessible regions of the Far North. Since the transportation of fuel there is extremely difficult, nuclear energy is the only reliable and constant source of energy.
What are they like?
There are thermal power plants (photos of which are in the article) industrial and "household", heating. As the name suggests, industrial power plants provide electricity and heat to large manufacturing enterprises.
Often they are built at the stage of the plant’s construction, making together with it a unified infrastructure. Accordingly, "household" varieties are being built not far from the sleeping residential districts of the city. In industrial thermal power plants, heat is transferred in the form of hot steam (not more than 4-5 km), in the case of heating - with the help of hot water (20-30 km).
Station Equipment Information
The main equipment of these enterprises are turbine units that convert mechanical energy into electricity, and boilers responsible for generating steam, which rotates the flywheels of the generators. The turbine unit includes both the turbine itself and the synchronous generator. Tubes with a back pressure of 0.7-1.5 Mn / m2 are placed on those thermal power plants that supply industrial facilities with heat and energy. Models with a pressure of 0.05-0.25 Mn / m2 serve to provide domestic consumers.
Efficiency Issues
In principle, all generated heat can be used fully. Here are just the amount of electricity that is generated at the CHP plant (the decoding of this term is already known to you) directly depends on the heat load. Simply put, in the spring-summer period, its production is almost reduced to zero. Thus, backpressure installations are used only to supply industrial facilities, in which the consumption value is more or less uniform throughout the entire period.
Condensing type plants
In this case, only the so-called “selection steam” is used to supply consumers with heat, and the rest of the heat is often simply lost, dissipated in the environment. To reduce energy losses, such CHPs must operate with minimal heat release to the condensing unit.
However, from the time of the USSR, such stations were built in which a hybrid mode was constructively provided: they can operate as ordinary condensing thermal power plants, but their turbine generator fully allows operation in backpressure mode.
Universal varieties
It is not surprising that it is the steam condensing units that have gained maximum distribution due to their versatility. So, only they make it possible to almost independently regulate the electric and thermal load. Even if no heat load is foreseen at all (in the case of a particularly hot summer), the population will be supplied with electricity according to the previous schedule (Western TPP in St. Petersburg).
"Thermal" varieties of thermal power plants
As you can already understand, heat generation at such power plants is extremely uneven throughout the year. In the ideal case, about 50% of hot water or steam is used to heat consumers, and the rest of the coolant is used to generate electricity. That is how the South-Western Thermal Power Plant works in the Northern capital.
Heat removal in most cases is carried out according to two schemes. If an open version is used, the hot steam from the turbines goes directly to consumers. If a closed operation scheme has been selected, the coolant is supplied after passing through the heat exchangers. The choice of scheme is determined on the basis of many factors. First of all, the distance from the object provided by heat and electricity, the number of people and the season are taken into account. So, the South-Western TPP in St. Petersburg works according to a closed scheme, as it provides greater efficiency.
Fuel Characteristics
Solid, liquid and gaseous fuels can be used . Since thermal power plants are often built in close proximity to large settlements and cities, it is often necessary to use its valuable types, gas and fuel oil. The use of coal and garbage as such in our country is quite limited, since far from all stations have installed modern effective air-cleaning equipment.
To clean the exhaust systems, special particulate traps are used. In order to disperse solid particles in sufficiently high layers of the atmosphere, they build pipes 200 to 250 meters high. As a rule, all cogeneration plants (CHP) are located at a sufficiently large distance from water sources (rivers and reservoirs). Therefore, artificial systems are used that include cooling towers. Direct-flow water supply is extremely rare, under very specific conditions.
Features of gas stations
Apart are gas thermal power plants. Heat supply to consumers is carried out not only due to the energy that is generated by burning
liquefied gas, but also by utilizing the heat of the gases that are generated in this process. The efficiency of such installations is extremely high. In some cases, nuclear power plants can also be used as CHP. This is especially common in some Arab countries.
There, these stations play two roles at once: they provide the population with electricity and industrial water, as they simultaneously perform the functions of desalination of sea water. And now we will consider the main thermal power plants of our country and neighboring countries.
Southwest, St. Petersburg
In our country, the Western TPP, which is located in St. Petersburg, is famous. Registered as OJSC “South-West Thermal Power Plant”. The construction of this modern facility pursued several functions at once:
- Compensation for the severe shortage of thermal energy, which prevented the intensification of the housing program.
- Improving the reliability and energy efficiency of the city system as a whole, since it was with this aspect that St. Petersburg had problems. CHPP partially solved this problem.
But this station is also known for being one of the first in Russia to comply with the strictest environmental requirements. For the new enterprise, the city government allocated an area of more than 20 hectares. The fact is that a reserve area left over from the Kirov District was allocated for the construction. In those parts there was an old ash collection from TPP-14, and therefore the area was not suitable for housing, but it was extremely well located.
The launch took place at the end of 2010, and almost the entire leadership of the city attended the ceremony. Two latest automatic boiler plants were commissioned.
Murmansk
The city of Murmansk is known as the base of our fleet on the Baltic Sea. But it is also characterized by extreme severity of climatic conditions, which imposes certain requirements on its energy system. It is not surprising that the Murmansk Thermal Power Plant is in many ways a completely unique technical object, even throughout the country.
It was commissioned in 1934, and since then continues to regularly supply residents of the city with heat and electricity. However, in the first five years, the Murmansk CHPP was an ordinary power plant. The first 1150 meters of the heating main were laid only in 1939. The point is the launched Nizhne-Tulomskaya hydroelectric power station, which almost completely blocked the city's electricity needs, and therefore it became possible to free part of the heat generation for heating urban houses.
The station is characterized by the fact that it works in a balanced mode all year, since its thermal and “energy” output are approximately equal. However, in the conditions of the polar night, the CHPP at some peak moments begins to use most of the fuel specifically for generating electricity.
Novopolotsk station, Belarus
The design and construction of this facility began in August 1957. The new Novopolotsk TPP was supposed to solve the issue of not only the heat supply of the city, but also the provision of electricity to the oil refinery being built in the same area. In March 1958, the project was finally signed, approved and approved.
The first phase was commissioned in 1966. The second was launched in 1977. At the same time, the Novopolotsk TPP was modernized for the first time, its peak power was increased to 505 MW, and a little later they laid down the third phase of construction, completed in 1982. In 1994, the station was converted to liquefied natural gas.
To date, about 50 million US dollars have already been invested in the modernization of the enterprise. Thanks to such an impressive cash infusion, the enterprise was not only completely converted to gas, but also received a huge amount of completely new equipment, which will allow the station to last another decades.
conclusions
Oddly enough, but today it is the outdated CHP plants that are truly universal and promising stations. Using modern neutralizers and filters, it is possible to heat water by burning almost all the garbage that the village produces. In this case, triple benefits are achieved:
- Landfills are unloaded and cleared.
- The city receives cheap electricity.
- The problem with heating is being solved.
In addition, in coastal areas it is quite realistic to build thermal power plants, which will simultaneously be desalination plants for sea water. Such a liquid is quite suitable for irrigation, for livestock complexes and industrial enterprises. In short, the true technology of the future!