Geothermal energy resources in Russia have significant industrial potential, including energy potential. The Earth's heat reserves with a temperature of 30-40 °C (Fig. 17.20, see color insert) are available throughout almost the entire territory of Russia, and in some regions there are geothermal resources with temperatures up to 300 °C. Depending on the temperature, geothermal resources are used in various sectors of the national economy: electric power, district heating, industry, agriculture, balneology.
At temperatures of geothermal resources above 130 °C, it is possible to generate electricity using single-circuit geothermal power plants(GeoES). However, a number of regions of Russia have significant reserves of geothermal waters with lower temperatures of the order of 85 ° C and higher (Fig. 17.20, see color insert). In this case, it is possible to obtain electricity from a GeoPP with a binary cycle. Binary power plants are double-circuit stations using their own working fluid in each circuit. Binary stations are also sometimes classified as single-circuit stations that operate on a mixture of two working fluids - ammonia and water (Fig. 17.21, see color insert).
The first geothermal power plants in Russia were built in Kamchatka in 1965-1967: Pauzhetskaya GeoPP, which operates and currently produces the cheapest electricity in Kamchatka, and Paratunka GeoPP with a binary cycle. Subsequently, about 400 GeoPPs with a binary cycle were built in the world.
In 2002, the Mutnovskaya GeoPP with two power units with a total capacity of 50 MW was put into operation in Kamchatka.
The technological scheme of the power plant provides for the use of steam obtained by two-stage separation of a steam-water mixture taken from geothermal wells.
After separation, steam with a pressure of 0.62 MPa and a dryness degree of 0.9998 enters a two-flow steam turbine having eight stages. A generator with a nominal power of 25 MW and a voltage of 10.5 kV operates in tandem with a steam turbine.
To ensure environmental cleanliness in technological scheme The power plant is equipped with a system for pumping condensate and separator back into the earth's layers, as well as preventing emissions of hydrogen sulfide into the atmosphere.
Geothermal resources are widely used for heating purposes, especially in the direct use of hot geothermal water.
It is advisable to use low-potential geothermal heat sources with a temperature of 10 to 30 °C using heat pumps. A heat pump is a machine designed to transfer internal energy from coolant with low temperature to coolant with high temperature using external influence to do work. Based on the operating principle heat pump lies the reverse Carnot cycle.
The heat pump, consuming kW of electrical power, supplies the heating system with 3 to 7 kW of thermal power. The transformation coefficient varies depending on the temperature of the low-grade geothermal source.
Heat pumps are widely used in many countries around the world. The most powerful heat pump installation operates in Sweden with a thermal capacity of 320 MW and uses the heat of the Baltic Sea water.
The efficiency of using a heat pump is determined mainly by the ratio of prices for electric and thermal energy, as well as the transformation coefficient, indicating how many times more thermal energy is produced compared to the electrical (or mechanical) energy expended.
The operation of heat pumps is most economical during the period of minimum loads in the power system. Their operation can help level out the electrical load schedules of the power system.
Literature for self-study
17.1.Usage water energy: textbook for universities / ed. Yu.S. Vasilyeva. -
4th ed., revised. and additional M.: Energoatomizdat, 1995.
17.2.Vasiliev Yu.S., Vissarionov V.I., Kubyshkin L.I. Hydropower solution
Russian tasks on a computer. M.: Energoatomizdat, 1987.
17.3.Neporozhny P.S., Obrezkov V.I. Introduction to the specialty. Hydroelectric power
tick: tutorial for universities. - 2nd ed., revised. and additional M: Energoatomizdat,
1990.
17.4.Water-energy and water-economic calculations: textbook for universities /
edited by IN AND. Vissarionova. M.: MPEI Publishing House, 2001.
17.5.Calculation solar energy resources: textbook for universities / ed.
IN AND. Vissarionova. M.: MPEI Publishing House, 1997.
17.6.Resources and efficiency of use of renewable energy sources
in Russia / Team of authors. St. Petersburg: Nauka, 2002.
17.7.Dyakov A.F., Perminov E.M., Shakaryan Yu.G. Wind energy in Russia. State
and development prospects. M.: MPEI Publishing House, 1996.
17.8.Calculation wind energy resources: textbook for universities / ed. IN AND. Wissa
Rionova. M.: MPEI Publishing House, 1997.
17.9.Mutnovsky geothermal electrical complex in Kamchatka / O.V. Britvin,
3.4 CALCULATION OF GEOTHERMAL POWER PLANT
Let's calculate the thermal circuit of a binary type geothermal power plant, according to.
Our geothermal power plant consists of two turbines:
The first operates on saturated water vapor obtained in an expander. Electric power - ;
The second one operates on saturated steam of refrigerant R11, which evaporates due to the heat of water removed from the expander.
Water from geothermal wells with pressure pgw and temperature tgw enters the expander. Dry saturated steam with pressure pp. This steam is sent to a steam turbine. The remaining water from the expander goes to the evaporator, where it is cooled and ends back into the well. Temperature pressure in the evaporation unit = 20°C. The working fluids expand in turbines and enter condensers, where they are cooled with water from the river at temperature thw. Heating of water in the condenser = 10°C, and subheating to saturation temperature = 5°C.
Relative internal efficiencies of turbines. Electromechanical efficiency of turbogenerators = 0.95.
The initial data is given in Table 3.1.
Table 3.1. Initial data for calculating GeoPP
Schematic diagram of a binary type GeoPP (Fig. 3.2).
Rice. 3.2. Schematic diagram of GeoPP.
According to the diagram in Fig. 3.2 and the initial data we carry out calculations.
Calculation of the circuit of a steam turbine operating on dry saturated water steam
Steam temperature at the turbine condenser inlet:
where is the temperature of the cooling water at the condenser inlet; - heating water in the condenser; - temperature difference in the condenser.
The steam pressure in the turbine condenser is determined from tables of properties of water and water steam:
Available heat drop per turbine:
where is the enthalpy of dry saturated steam at the turbine inlet; - enthalpy at the end of the theoretical process of steam expansion in the turbine.
Steam consumption from the expander to the steam turbine:
where is the relative internal efficiency of the steam turbine; - electromechanical efficiency of turbogenerators.
Geothermal water expander calculation
Expander Heat Balance Equation
where is the flow rate of geothermal water from the well; - enthalpy of geothermal water from a well; - water flow from the expander to the evaporator; - enthalpy of geothermal water at the exit from the expander. It is determined from tables of properties of water and water vapor as the enthalpy of boiling water.
Expander Material Balance Equation
By solving these two equations together, it is necessary to determine and.
The temperature of geothermal water at the outlet of the expander is determined from the tables of the properties of water and water vapor as the saturation temperature at the pressure in the expander:
Determination of parameters at characteristic points of the thermal circuit of a turbine operating in freon
Freon vapor temperature at the turbine inlet:
Freon vapor temperature at the turbine outlet:
The enthalpy of freon vapor at the turbine inlet is determined from the p-h diagram for freon on the saturation line at:
240 kJ/kg.
The enthalpy of the freon vapor at the outlet of the turbine is determined from the p-h diagram for the freon at the intersection of the lines and the temperature line:
220 kJ/kg.
The enthalpy of the boiling freon at the outlet of the condenser is determined from the p-h diagram for the freon on the curve for the boiling liquid by temperature:
215 kJ/kg.
Evaporator calculation
Geothermal water temperature at the evaporator outlet:
Evaporator heat balance equation:
where is the heat capacity of water. Take =4.2 kJ/kg.
From this equation it is necessary to determine.
Calculation of the power of a turbine operating on freon
where is the relative internal efficiency of the freon turbine; - electromechanical efficiency of turbogenerators.
Determining pump power for pumping geothermal water into a well
where is the pump efficiency, assumed to be 0.8; - average specific volume of geothermal water.
Electric power of GeoPP
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CALCULATION OF GEOTHERMAL POWER PLANT
Let's calculate the thermal circuit of a binary type geothermal power plant, according to.
Our geothermal power plant consists of two turbines:
The first operates on saturated water vapor obtained in an expander. Electric power - ;
The second one operates on saturated steam of refrigerant R11, which evaporates due to the heat of water removed from the expander.
Water from geothermal wells with pressure pgw and temperature tgw enters the expander. The expander produces dry saturated steam with a pressure of pp. This steam is sent to a steam turbine. The remaining water from the expander goes to the evaporator, where it is cooled and ends back into the well. Temperature pressure in the evaporation unit = 20°C. The working fluids expand in turbines and enter condensers, where they are cooled with water from the river at temperature thw. Heating of water in the condenser = 10°C, and subheating to saturation temperature = 5°C.
Relative internal efficiencies of turbines. Electromechanical efficiency of turbogenerators = 0.95.
The initial data is given in Table 3.1.
Table 3.1. Initial data for calculating GeoPP
Schematic diagram of a binary type GeoPP (Fig. 3.2).
Rice. 3.2.
According to the diagram in Fig. 3.2 and the initial data we carry out calculations.
Calculation of the circuit of a steam turbine operating on dry saturated water steam
Steam temperature at the turbine condenser inlet:
where is the temperature of the cooling water at the condenser inlet; - heating water in the condenser; - temperature difference in the condenser.
The steam pressure in the turbine condenser is determined from tables of properties of water and water steam:
Available heat drop per turbine:
where is the enthalpy of dry saturated steam at the turbine inlet; - enthalpy at the end of the theoretical process of steam expansion in the turbine.
Steam consumption from the expander to the steam turbine:
where is the relative internal efficiency of the steam turbine; - electromechanical efficiency of turbogenerators.
Geothermal water expander calculation
Expander Heat Balance Equation
where is the flow rate of geothermal water from the well; - enthalpy of geothermal water from a well; - water flow from the expander to the evaporator; - enthalpy of geothermal water at the exit from the expander. It is determined from tables of properties of water and water vapor as the enthalpy of boiling water.
Expander Material Balance Equation
By solving these two equations together, it is necessary to determine and.
The temperature of geothermal water at the outlet of the expander is determined from the tables of the properties of water and water vapor as the saturation temperature at the pressure in the expander:
Determination of parameters at characteristic points of the thermal circuit of a turbine operating in freon
Freon vapor temperature at the turbine inlet:
Freon vapor temperature at the turbine outlet:
The enthalpy of freon vapor at the turbine inlet is determined from the p-h diagram for freon on the saturation line at:
240 kJ/kg.
The enthalpy of the freon vapor at the outlet of the turbine is determined from the p-h diagram for the freon at the intersection of the lines and the temperature line:
220 kJ/kg.
The enthalpy of the boiling freon at the outlet of the condenser is determined from the p-h diagram for the freon on the curve for the boiling liquid by temperature:
215 kJ/kg.
Evaporator calculation
Geothermal water temperature at the evaporator outlet:
Evaporator heat balance equation:
where is the heat capacity of water. Take =4.2 kJ/kg.
From this equation it is necessary to determine.
Calculation of the power of a turbine operating on freon
where is the relative internal efficiency of the freon turbine; - electromechanical efficiency of turbogenerators.
Determining pump power for pumping geothermal water into a well
where is the pump efficiency, assumed to be 0.8; - average specific volume of geothermal water.
Purpose of the lecture: show the possibilities and ways of using geothermal heat in power supply systems.
Heat in the form of hot springs and geysers can be used to generate electricity by various schemes at geothermal power plants (GeoPP). The most easily implemented scheme is the one using steam of liquids having a low boiling point. Hot water from natural sources, heating such a liquid in the evaporator, turns it into steam, which is used in the turbine and serves as a drive for the current generator.
Figure 1 shows a cycle with one working fluid, for example water or freon ( A); cycle with two working fluids - water and freon ( b); direct steam cycle ( V) and double-circuit cycle ( G).
Technologies for the production of electrical energy largely depend on the thermal potential of thermal waters.
Drawing. 1 - Examples of organizing a cycle for electricity production:
I – geothermal source; II – turbine cycle; III – cooling water
High-potential deposits allow the use of almost traditional designs of thermal power plants with steam turbines.
Table 1 -Specifications geothermal power plants
Figure 2 shows the most simple circuit a small power plant (GeoPP) using the heat of a hot underground source.
Water from a hot spring with a temperature of about 95 °C is supplied by pump 2 to gas remover 3, where the gases dissolved in it are separated.
Next, the water enters the evaporator 4, in which it is converted into saturated steam and slightly overheated due to the heat of the steam (from the auxiliary boiler), which was previously exhausted in the condenser ejector.
Slightly superheated steam does work in turbine 5, on the shaft of which there is a current generator. The exhaust steam is condensed in condenser 6, cooled with water at normal temperature.
Figure 2-. Scheme of a small GeoPP:
1 – receiver hot water; 2 – hot water pump; 3 – gas remover;
4 – evaporator; 5 - steam turbine with current generator; 6 – capacitor; 7 – circulation pump; 8 – cooling water receiver
Such simple installations operated in Africa already in the 50s.
An obvious design option for a modern power plant is a geothermal power plant with a low-boiling working substance, shown in Figure 3. Hot water from the storage tank enters the evaporator 3, where it gives off its heat to some substance with a low boiling point. Such substances can be carbon dioxide, various freons, sulfur hexafluoride, butane, etc. Condenser 6 is a mixing type, which is cooled by cold liquid butane coming from a surface air cooler. Part of the butane from the condenser is supplied by feed pump 9 to the heater 10, and then to the evaporator 3.
An important feature of this scheme is the ability to work in winter time with low condensation temperatures. This temperature can be close to zero or even negative, since all of the listed substances have very low temperatures freezing. This allows you to significantly expand the temperature limits used in the cycle.
Drawing 3. Scheme of a geothermal power plant with a low-boiling working substance:
1 – well, 2 – storage tank, 3 – evaporator, 4 – turbine, 5 – generator, 6 – condenser, 7 – circulation pump, 8 – surface air cooler, 9 – feed pump, 10 – working substance heater
Geothermal power station With direct using natural steam.
The simplest and most affordable geothermal power plant is a steam turbine plant with back pressure. Natural steam from the well is supplied directly to the turbine and then released into the atmosphere or into a device that captures valuable chemicals. The backpressure turbine can be supplied with secondary steam or steam obtained from the separator. According to this scheme, the power plant operates without capacitors, and there is no need for a compressor to remove non-condensable gases from the capacitors. This installation is the simplest; capital and operating costs are minimal. She takes small area, requires almost no auxiliary equipment and can be easily adapted as a portable geothermal power plant (Figure 4).
Figure 4 - Scheme of a geothermal power plant with direct use of natural steam:
1 – well; 2 – turbine; 3 – generator;
4 – exit to the atmosphere or to a chemical plant
The considered scheme may be the most profitable for those areas where there are sufficient reserves of natural steam. Rational operation provides the opportunity efficient work such an installation even with variable well flow rates.
There are several such stations operating in Italy. One of them has a power of 4 thousand kW with a specific steam consumption of about 20 kg/s or 80 t/h; the other has a capacity of 16 thousand kW, where four turbogenerators with a capacity of 4 thousand kW each are installed. The latter is supplied with steam from 7–8 wells.
Geothermal power plant with condensing turbine and direct use of natural steam (Figure 5) is the most modern scheme for generating electrical energy.
Steam from the well is supplied to the turbine. Spent in the turbine, it enters the mixing condenser. A mixture of cooling water and condensate of steam already exhausted in the turbine is discharged from the condenser into an underground tank, from where it is taken circulation pumps and is sent to a cooling tower for cooling. From the cooling tower, the cooling water again flows into the condenser (Figure 5).
Many geothermal power plants operate according to this scheme with some modifications: Larderello-2 (Italy), Wairakei ( New Zealand) and etc.
Application area double-circuit power plants using low-boiling working substances (freon-R12, water-ammonia mixture,) is the use of heat from thermal waters with a temperature of 100...200 °C, as well as separated water at hydrothermal steam deposits.
Figure 5 - Scheme of a geothermal power plant with a condensing turbine and direct use of natural steam:
1 – well; 2 – turbine; 3 – generator; 4 – pump;
5 – capacitor; 6 – cooling tower; 7 – compressor; 8 – reset
Combined production of electrical and thermal energy
Combined production of electrical and thermal energy is possible at geothermal thermal power plants (GeoTES).
The simplest diagram of a vacuum-type geothermal power plant for using the heat of hot water with temperatures up to 100 °C is shown in Figure 6.
The operation of such a power plant proceeds as follows. Hot water from well 1 enters accumulator tank 2. In the tank, it is freed from gases dissolved in it and sent to expander 3, in which a pressure of 0.3 atm is maintained. At this pressure and at a temperature of 69 °C, a small part of the water turns into steam and is sent to vacuum turbine 5, and the remaining water is pumped by pump 4 into the heat supply system. The steam exhausted in the turbine is discharged into the mixing condenser 7. To remove air from the condenser, a vacuum pump 10 is installed. A mixture of cooling water and exhaust steam condensate is taken from the condenser by pump 8 and sent for cooling to the ventilation cooling tower 9. Water cooled in the cooling tower is supplied to the condenser by gravity due to vacuum.
Verkhne-Mutnovskaya GeoTPP with a capacity of 12 MW (3x4 MW) is a pilot stage of the Mutnovskaya GeoTPP with a design capacity of 200 MW, created to supply power to the Petropavlovsk-Kamchatsky industrial region.
Figure 6 -. Diagram of a vacuum geothermal power plant with one expander:
1 – well, 2 – storage tank, 3 – expander, 4 – hot water pump, 5 – vacuum turbine 750 kW, 6 – generator, 7 – mixing condenser,
8 – cooling water pump, 9 – fan cooling tower, 10 – vacuum pump
At the Pauzhetskaya Geothermal Power Plant (south of Kamchatka) with a capacity of 11 MW, only separated geothermal steam from the steam-water mixture obtained from geothermal wells is used in steam turbines. A large amount of geothermal water (about 80 total flow PVA) with a temperature of 120 °C is discharged into the spawning river Ozernaya, which leads not only to a loss of the thermal potential of the geothermal coolant, but also significantly worsens the ecological condition of the river.
Heat pumps
Heat pump- a device for transferring thermal energy from a source of low-grade thermal energy with a low temperature to a coolant consumer with a higher temperature. Thermodynamically, a heat pump is an inverted refrigeration machine. If in refrigeration machine the main goal is to produce cold by removing heat from any volume by the evaporator, and the condenser discharges heat into environment, then in a heat pump the picture is the opposite (Figure 7). The condenser is a heat exchanger that produces heat for the consumer, and the evaporator is a heat exchanger that utilizes low-grade heat located in reservoirs, soils, wastewater etc. Depending on the principle of operation, heat pumps are divided into compression and absorption. Compression heat pumps are always driven by an electric motor, while absorption heat pumps can also use heat as an energy source. The compressor also needs a source of low-grade heat.
During operation, the compressor consumes electricity. The ratio of generated thermal energy and consumed electrical energy is called the transformation ratio (or heat conversion coefficient) and serves as an indicator of the efficiency of the heat pump. This value depends on the difference in temperature levels in the evaporator and condenser: the greater the difference, the smaller this value.
By type of coolant in the input and output circuits, pumps are divided into six types: “ground-water”, “water-water”, “air-water”, “ground-air”, “water-air”, “air-air”.
When using soil energy as a heat source, the pipeline in which the liquid circulates is buried in the ground 30-50 cm below the freezing level of the soil in a given region (Figure 8). To install a heat pump with a capacity of 10 kW, an earthen circuit 350-450 m long is required, for the installation of which a plot of land with an area of about 400 m² (20x20 m) will be required.
Figure 7 – Heat pump operation diagram
Figure 8 - Using soil energy as a heat source
The advantages of heat pumps include, first of all, efficiency: to transfer 1 kWh of thermal energy to the heating system, the heat pump installation needs to spend 0.2-0.35 kWh of electricity. All systems operate using closed loops and require virtually no operating costs, other than the cost of electricity required to operate the equipment, which can be obtained from wind and solar power plants. The payback period for heat pumps is 4-9 years, with a service life of 15-20 years before major repairs.
The actual efficiency values of modern heat pumps are of the order of COP = 2.0 at a source temperature of −20 °C, and of the order of COP = 4.0 at a source temperature of +7 °C.
GEOTHERMAL ENERGY
Skotarev Ivan Nikolaevich
2nd year student, department physicists SSAU, Stavropol
Khashchenko Andrey Alexandrovich
scientific supervisor, can. physics and mathematics sciences, Associate Professor, St. State Agrarian University, Stavropol
Nowadays humanity doesn’t think much about what it will leave to future generations. People mindlessly pump and dig up minerals. Every year the population of the planet is growing, and therefore the need for even more energy resources such as gas, oil and coal is increasing. This cannot continue for long. Therefore, now, in addition to the development of the nuclear industry, the use of alternative energy sources is becoming relevant. One of the promising areas in this area is geothermal energy.
Most of the surface of our planet has significant reserves of geothermal energy due to significant geological activity: active volcanic activity in initial periods the development of our planet and also to this day, radioactive decay, tectonic shifts and the presence of areas of magma in the earth's crust. In some places on our planet, especially a lot of geothermal energy accumulates. These are, for example, various valleys of geysers, volcanoes, underground accumulations of magma, which in turn heat the upper rocks.
Speaking in simple language geothermal energy is energy internal regions Earth. For example, volcanic eruptions clearly indicate the enormous temperature inside the planet. This temperature gradually decreases from the hot inner core to the Earth's surface ( picture 1).
Figure 1. Temperature in different layers of the earth
Geothermal energy has always attracted people due to its potential. useful application. After all, man in the process of his development came up with many useful technologies and looked for profit and profit in everything. This is what happened with coal, oil, gas, peat, etc.
For example, in some geographical areas the use of geothermal sources can significantly increase energy production, since geothermal power plants (GeoTES) are one of the cheapest alternative energy sources, because the upper three-kilometer layer of the Earth contains over 1020 J of heat suitable for generating electricity. Nature itself gives a person a unique source of energy; it is only necessary to use it.
There are currently 5 types of geothermal energy sources:
1. Geothermal dry steam deposits.
2. Sources of wet steam. (a mixture of hot water and steam).
3. Geothermal water deposits (contain hot water or steam and water).
4. Dry hot rocks heated by magma.
5. Magma (molten rocks heated to 1300 °C).
Magma transfers its heat to rocks, and their temperature rises with increasing depth. According to available data, the temperature of rocks increases on average by 1 °C for every 33 m of depth (geothermal step). There is great diversity in the world temperature conditions geothermal energy sources, which will determine the technical means for its use.
Geothermal energy can be used in two main ways - to generate electricity and to heat various objects. Geothermal heat can be converted into electricity if the coolant temperature reaches more than 150 °C. It is precisely the use of the internal regions of the Earth for heating that is the most profitable and effective and also very affordable. Direct geothermal heat depending on the temperature, it can be used for heating buildings, greenhouses, swimming pools, drying agricultural and fish products, evaporating solutions, growing fish, mushrooms, etc. .
All geothermal installations existing today are divided into three types:
1. stations whose operation is based on dry steam deposits - this is a direct scheme.
Dry steam power plants appeared earlier than anyone else. In order to obtain the required energy, steam is passed through a turbine or generator ( figure 2).
Figure 2. Geothermal power plant of direct circuit
2. stations with a separator using hot water deposits under pressure. Sometimes a pump is used for this, which provides the required volume of incoming energy - an indirect scheme.
This is the most common type of geothermal plant in the world. Here the waters are pumped under high pressure to generator sets. The hydrothermal solution is pumped into the evaporator to reduce the pressure, resulting in the evaporation of part of the solution. Next, steam is formed, which makes the turbine work. The remaining liquid may also be beneficial. Usually it is passed through another evaporator to obtain additional power ( figure 3).
Figure 3. Indirect geothermal power plant
They are characterized by the absence of interaction between the generator or turbine and steam or water. The principle of their operation is based on reasonable use underground water moderate temperature.
Typically the temperature should be below two hundred degrees. The binary cycle itself consists of using two types of water - hot and moderate. Both streams are passed through a heat exchanger. The hotter liquid evaporates the colder one, and the vapors formed as a result of this process drive the turbines.
Figure 4. Schematic of a geothermal power plant with a binary cycle.
As for our country, geothermal energy ranks first in terms of potential possibilities for its use due to the unique landscape and natural conditions. The discovered reserves of geothermal waters with temperatures from 40 to 200 °C and a depth of up to 3500 m on its territory can provide approximately 14 million m3 of hot water per day. Large reserves of underground thermal waters are located in Dagestan, North Ossetia, Checheno-Ingushetia, Kabardino-Balkaria, Transcaucasia, Stavropol and Krasnodar region, Kazakhstan, Kamchatka and a number of other regions of Russia. For example, in Dagestan, thermal waters have been used for heat supply for a long time.
The first geothermal power plant was built in 1966 at the Pauzhetsky field on the Kamchatka Peninsula to supply electricity to surrounding villages and fish processing plants, thereby promoting local development. The local geothermal system can provide energy for power plants with a capacity of up to 250-350 MW. But this potential is only used by a quarter.
Territory Kuril Islands has a unique and at the same time complex landscape. Power supply to the cities located there comes with great difficulties: the need to deliver means of subsistence to the islands by sea or air, which is quite expensive and takes a lot of time. Geothermal resources of the islands this moment allow you to receive 230 MW of electricity, which can meet all the region’s needs for energy, heat, and hot water supply.
On the island of Iturup, resources of a two-phase geothermal coolant have been found, the power of which is sufficient to meet the energy needs of the entire island. On the southern island of Kunashir there is a 2.6 MW GeoPP, which is used to generate electricity and heat supply to the city of Yuzhno-Kurilsk. It is planned to build several more GeoPPs with a total capacity of 12-17 MW.
The most promising regions for the use of geothermal sources in Russia are the south of Russia and Far East. The Caucasus, Stavropol region, and Krasnodar region have enormous potential for geothermal energy.
The use of geothermal waters in the central part of Russia requires high costs due to the deep occurrence of thermal waters.
In the Kaliningrad region, there are plans to implement a pilot project for geothermal heat and electricity supply to the city of Svetly based on a binary GeoPP with a capacity of 4 MW.
Geothermal energy in Russia is focused both on the construction of large facilities and on the use of geothermal energy for individual homes, schools, hospitals, private shops and other facilities using geothermal circulation systems.
In the Stavropol Territory, at the Kayasulinskoye field, the construction of an expensive experimental Stavropol Geothermal Power Plant with a capacity of 3 MW was started and suspended.
In 1999, the Verkhne-Mutnovskaya GeoPP was put into operation ( Figure 5).
Figure 5. Verkhne-Mutnovskaya GeoPP
It has a capacity of 12 MW (3x4 MW) and is a pilot stage of the Mutnovskaya GeoPP with a design capacity of 200 MW, created to supply power to the industrial region of Petropavlovsk-Kamchatsk.
But despite the great advantages in this direction, there are also disadvantages:
1. The main one is the need to pump waste water back into the underground aquifer. Thermal waters contain large amounts of salts of various toxic metals (boron, lead, zinc, cadmium, arsenic) and chemical compounds(ammonia, phenols), which makes it impossible to discharge these waters into natural water systems located on the surface.
2. Sometimes an operating geothermal power plant may stop working as a result of natural changes in the earth's crust.
3. Find appropriate place to build a geothermal power plant and obtaining permission from local authorities and consent from residents for its construction can be problematic.
4. The construction of a GeoPP may negatively affect land stability in the surrounding region.
Most of these shortcomings are minor and completely solvable.
In today's world, people do not think about the consequences of their decisions. After all, what will they do if they run out of oil, gas and coal? People are used to living in comfort. They won’t be able to heat their houses with wood for a long time, because the large population will need a huge number wood, which will naturally lead to large-scale deforestation and leave the world without oxygen. Therefore, in order to prevent this from happening, it is necessary to use the resources available to us sparingly, but with maximum efficiency. Just one way to solve this problem is the development of geothermal energy. Of course, it has its pros and cons, but its development will greatly facilitate the continued existence of humanity and will play a big role in its further development.
Now this direction is not very popular, because the oil and gas industry dominates the world and large companies are in no hurry to invest in the development of a much-needed industry. Therefore, for the further progress of geothermal energy, investments and government support are necessary, without which it is simply impossible to implement anything on a national scale. The introduction of geothermal energy into the country's energy balance will allow:
1. increase energy security, on the other hand, reduce the harmful impact on the environment compared to traditional sources.
2. develop the economy, because the liberated cash it will be possible to invest in other industries, social development states, etc.
In the last decade, the use of non-traditional renewable energy sources has experienced a real boom in the world. The scale of use of these sources has increased several times. It is capable of radically and on the most economic basis solving the problem of energy supply to these areas, which use expensive imported fuel and are on the verge of an energy crisis, improve the social situation of the population of these areas, etc. This is exactly what we are seeing in countries Western Europe(Germany, France, Great Britain), Northern Europe (Norway, Sweden, Finland, Iceland, Denmark). This is explained by the fact that they have high economic development and are very dependent on fossil resources, and therefore the heads of these states, together with business, are trying to minimize this dependence. In particular, the development of geothermal energy in the Nordic countries is favored by the availability of large quantity geysers and volcanoes. It’s not for nothing that Iceland is called the country of volcanoes and geysers.
Now humanity is beginning to understand the importance of this industry and is trying to develop it as much as possible. The use of a wide range of diverse technologies makes it possible to reduce energy consumption by 40-60% and at the same time provide real economic development. And the remaining needs for electricity and heat can be met through more efficient production, through restoration, through combining the generation of thermal and electrical energy, as well as through the use of renewable resources, which makes it possible to abandon certain types of power plants and reduce emissions carbon dioxide by about 80%.
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