The main task of our civilization is to prevent the transition of the biosphere to a state of bifurcation. The way out of this state is ambiguous. It can also give new stimuli for development, as happened with the Cro-Magnons as a result of the Neolithic catastrophe, or it can lead to complete extinction, as happened with the people of the Mousterian culture. The risk is so high that humanity cannot afford it. Hence, such a categorical formulation of the main strategic goal of modern civilization.

Where do we get energy from now?

The bulk of electricity is currently produced at thermal power plants (TPP). This is usually followed by hydroelectric power plants (HPPs) and nuclear power plants (NPPs).

1) Thermal power plants
In most countries of the world, the share of electricity generated by thermal power plants is more than 50%. Coal, fuel oil, gas, shale are usually used as fuel at TPPs. Fossil fuels are non-renewable resources. According to many estimates, there will be enough coal on the planet for 100-300 years, oil for 40-80 years, natural gas for 50-120 years.
The efficiency of the TPP is 36-39% on average. Along with fuel, TPP consumes a significant amount of water. A typical thermal power plant with a capacity of 2 million kW consumes 18,000 tons of coal, 2,500 tons of fuel oil, and 150,000 m3 of water daily. To cool the waste steam at TPPs, 7 million m3 of water are used daily, which leads to thermal pollution of the cooling reservoir.
Thermal power plants are characterized by high radiation and toxic environmental pollution. This is due to the fact that ordinary coal and its ash contain trace amounts of uranium and a number of toxic elements in much higher concentrations than the earth's crust.
During the construction of large thermal power plants or their complexes, pollution is even more significant. In this case, new effects may arise, for example, due to the excess of the rate of oxygen combustion over the rate of its formation due to photosynthesis of terrestrial plants in a given territory, or caused by an increase in the concentration of carbon dioxide in the surface layer.
The most promising fossil fuel source is coal (its reserves are huge compared to oil and gas reserves). The main world coal reserves are concentrated in Russia, China and the United States. At the same time, the main amount of energy is currently generated at TPPs through the use of petroleum products. Thus, the structure of fossil fuel reserves does not correspond to the structure of its current consumption in energy production. In the future, the transition to a new structure of consumption of fossil fuels (coal) will cause significant environmental problems, material costs and changes in the entire industry. A number of countries have already started energy restructuring.

2) Hydroelectric power plants
The main advantages of hydroelectric power plants are low cost of generated electricity, quick payback (the cost is about 4 times lower, and payback is 3-4 times faster than at TPPs), high maneuverability, which is very important during periods of peak loads, the possibility of energy accumulation.
But even with the full use of the potential of all the rivers of the Earth, no more than a quarter of the modern needs of mankind can be provided. Less than 20% of the hydropower potential is used in Russia. In developed countries, the efficiency of using water resources is 2-3 times higher, i.e. here Russia has certain reserves. However, the construction of hydroelectric power plants (especially on flat rivers) leads to many environmental problems. Reservoirs, necessary to ensure the uniform operation of hydroelectric power plants, cause climate change in the adjacent territories at distances of up to hundreds of kilometers, and are natural accumulators of pollution.
Blue-green algae develop in reservoirs, eutrophication processes are accelerated, which leads to a deterioration in water quality and disrupts the functioning of ecosystems. During the construction of reservoirs, natural spawning grounds are disturbed, fertile lands are flooded, and the level of groundwater changes.
More promising is the construction of hydroelectric power plants on mountain rivers. This is due to the higher hydropower potential of mountain rivers compared to plain rivers. When constructing reservoirs in mountainous areas, large areas of fertile land are not withdrawn from land use.

3) Nuclear power plants
Nuclear power plants do not produce carbon dioxide, and the volume of other atmospheric pollutants compared to thermal power plants is also small. The amount of radioactive substances generated during the operation of a nuclear power plant is relatively small. For a long time, nuclear power plants were presented as the most environmentally friendly type of power plants and as a promising replacement for thermal power plants that have an impact on global warming. However, the process of safe operation of the nuclear power plant has not yet been decided. On the other hand, replacing the bulk of thermal power plants with nuclear power plants to eliminate their contribution to atmospheric pollution on a global scale is not feasible due to huge economic costs.
The Chernobyl disaster led to a radical change in the attitude of the population towards nuclear power plants in the regions where the plants are located or their possible construction. Therefore, the prospects for the development of nuclear energy in the coming years are unclear. Among the main problems of using nuclear power plants are the following.
1. Safety of reactors. All modern types of reactors put humanity at risk of a global accident like the Chernobyl one. Such an accident can occur due to the fault of the designers, due to operator error or as a result of a terrorist act. The principle of internal self-protection of the reactor core in the event of an accident developing according to the worst scenario with core melt should be an indisputable requirement in the design of reactors. Nuclear technology is complex. It took years of analysis and accumulated experience just to realize the possibility of some types of accidents.
Uncertainties about security will never be fully resolved in advance. A large number of them will be discovered only during the operation of new reactors.
3. Reducing carbon dioxide emissions. It is believed that displacing thermal power plants by nuclear power plants will help solve the problem of reducing emissions of carbon dioxide, one of the main greenhouse gases that contribute to global warming. However, in fact, natural gas combined cycle power plants are not only much more economical than nuclear power plants, but at the same cost, significantly greater reductions in carbon dioxide emissions are achieved than when using nuclear energy, taking into account the entire fuel cycle (energy consumption during the extraction and enrichment of uranium, the manufacture of nuclear fuel and other costs at the "entry" and "exit").
4. Decommissioning of reactors at nuclear power plants. By 2010, half of the nuclear power plants operating in the world were 25 years old or more. After that, a procedure for decommissioning the reactors is proposed. According to the World Nuclear Association (WNA), more than 130 industrial nuclear installations have already been decommissioned or are awaiting this procedure. And in all cases, the problem of disposal of radioactive waste arises, which must be reliably isolated and stored for a long time in special storage facilities. Many experts believe that these costs can be equal to the costs of building a nuclear power plant.
5. The danger of using nuclear power plants for the proliferation of nuclear weapons. Each reactor produces enough plutonium annually to create several atomic bombs. Spent nuclear fuel (SNF), which is regularly unloaded from reactors, contains not only plutonium, but also a whole range of hazardous radiation elements. Therefore, the IAEA is trying to keep under control the entire spent nuclear fuel management cycle in all countries where nuclear power plants operate.
A primitive atomic bomb can be made from the spent nuclear fuel of any nuclear power plant. If creating a bomb requires complex production, special equipment and trained specialists, then creating so-called dirty nuclear explosive devices is much easier, and here the danger is very great. Using such a "homemade" nuclear explosion, of course, will not happen, but there will be a strong radioactive contamination. Terrorists and extremists can make such devices on their own by purchasing the necessary fission materials on the nuclear black market. Such a market, sadly, exists, and the nuclear industry is a potential supplier of such materials.

Ecological and economic characteristics of the main renewable and alternative energy sources

It is believed that renewable energy sources (wind, solar, geothermal, wave, etc.), modular natural gas stations using fuel cells, utilization of waste heat and waste steam, like many other things, are real ways to protect against climate change without creating new threats to current and future generations. Let's consider these issues in more detail.

1) Direct use of solar energy
The power of solar radiation absorbed by the atmosphere and the earth's surface is 105 TW (1017 W). This figure seems enormous compared to the current global energy consumption of 10 TW. Therefore, it is considered the most promising type of non-traditional (alternative) energy.
The main methods for converting solar energy include, first of all, methods of direct use of solar energy - photoelectric conversion and thermodynamic cycle, as well as bioconversion.
The photoelectric method for converting solar energy is based on the features of the interaction of semiconductor materials with light radiation. In a photoelectric converter, free carriers are formed as a result of the absorption of a light quantum by a semiconductor; the separation of charges is carried out under the action of an electric field that arises inside the semiconductor. Theoretically, the efficiency of the converter can reach 28%.
The low density of solar radiation is one of the obstacles to its widespread use. To eliminate this drawback, various types of radiation concentrators are used in the design of photoelectric converters. The main advantages of photovoltaic installations are that they have no moving parts, their design is very simple, and production is technologically advanced. Their disadvantages include the destruction of the semiconductor material on time, the dependence of the efficiency of the system on its dustiness, the need to develop complex methods for cleaning batteries from contamination. All this limits the service life of photovoltaic converters.
Hybrid plants, consisting of photovoltaic converters and diesel generators, are already widely used for power supply in areas where there is no electrical distribution network. For example, this type of system provides electricity to the inhabitants of Cocos Island, located in the Torres Strait.

Energy is obtained from solar energy by thermodynamic conversion in much the same way as from other sources. However, such features of solar radiation as low power, daily and seasonal variability, dependence on weather conditions impose certain restrictions on the design of thermodynamic converters.
A conventional thermodynamic solar energy converter comprises a solar radiation capture system that is designed to partially compensate for low solar radiation density; a receiving system that converts solar energy into heat carrier energy; a system for transferring the coolant from the receiver to the accumulator or to the heat exchanger; a heat accumulator that provides mitigation of dependence on daily variability and weather conditions; heat exchangers forming the heating and cooling sources of the heat engine.
For medium-temperature accumulation (from 100 to 5500C), hydrates of oxides of alkaline earth metals are used. High-temperature accumulation (temperatures above 5500C) is carried out using reversible exo-endothermic reactions.
At present, the ideas of thermodynamic transformation are implemented in two types of circuits: tower-type heliostats and stations with a distributed energy receiver.
In a tower-type solar power plant, the energy from each heliostat is transmitted optically. The heliostats are controlled by a computer. Up to 80% of the cost of the station is the cost of heliostats. The system for collecting and transmitting energy in tower-type installations is very expensive. Therefore, such attitudes have not become widespread. In Mexico, USA, installations of this type with a capacity of 10 MW are in operation.
Stations with distributed receivers of solar energy turned out to be more promising. Axially rotating parabolic concentrators transmit energy to tubular receivers located on the focal line. Oil is usually used as a heat transfer medium. An unsolved problem in solar power plants is the issue of long-term storage of electricity. True, it should be noted that this issue has not been resolved not only in solar energy, but also in energy in general.

The wider adoption of solar energy is still hampered by the higher production cost in solar power plants compared to traditional energy sources. Solar energy has features that significantly complicate its widespread use. This is, first of all, a low energy flux density and its inconstancy, because the intensity of solar radiation depends on the season, day and weather conditions. Nevertheless, at the present time, there is a tendency of significant growth, both in the commissioned capacities and investments in this industry all over the world. In 2008-2009. new investments exceeded half of all investments in total energy production. In 2010, for the first time, the increase in capacities based on renewable energy sources exceeded the commissioning of traditional capacities. In terms of available capacities and investments, China, the USA, Germany, India and Brazil are in the lead in many respects. Against this background, the Russian target of 1.5% by 2010 and 4.5% of renewable energy sources in electricity production by 2020 looks very modest.
In addition, the use of solar energy presupposes the obligatory availability of energy storage units of sufficient capacity. As a rule, these are ordinary batteries. Therefore, if we consider the solar energy of the full cycle (taking into account the production of solar energy transducers and, especially, storage batteries), then the total effect of such energy on the pollution of the surrounding space turns out to be not so insignificant.

2) Bioconversion of solar energy
Biomass has been used as an energy source since ancient times. In the process of photosynthesis, solar energy is stored in the form of chemical energy in the green mass of plants. The energy stored in biomass can be used in the form of food by humans or animals, or for energy production in everyday life and production. Currently, up to 15% of the world's energy is produced from biomass.
The oldest, and still widely used, method of obtaining energy from biomass is to burn it. In rural areas, up to 85% of energy is obtained by this method. As a fuel, biomass has several advantages over fossil fuels. First of all, it is a renewable energy source. When biomass is burned, 10-20 times less sulfur is released and 3-5 times less ash than when burning coal. The amount of carbon dioxide released during the combustion of biomass is equal to the amount of carbon dioxide expended in the process of photosynthesis.
Biomass energy can be obtained from special crops. For example, in the subtropical zone of Russia, it is proposed to grow dwarf breeds of a fast-growing species of papaya. More than 5 tons of dry weight biomass are obtained from one hectare in 6 months on experimental plots, which can be used for biogas production. Promising species include fast-growing trees, plants rich in carbohydrates, which are used to obtain ethyl alcohol (for example, sugar cane). A method for producing alcohol from corn has been developed in the United States, and work is underway in Italy to develop a method for the cost-effective production of alcohol from sorghum. About 200 buses in Stockholm are already running on alcohol.

A widespread way of obtaining energy from biomass is to obtain biogas by anaerobic digestion. This gas contains about 70% methane. Biomethanogenesis was discovered back in 1776 by Volta, who discovered the methane content in bog gas. Biogas allows the use of gas turbines, which are the most modern means of heat power generation. Organic waste from agriculture and industry is used for biogas production. This direction is one of the most promising and promising ways to solve the problem of energy supply in rural areas. For example, out of 300 tons of dry matter of manure converted to biogas, the energy yield is about 30 tons of oil equivalent.
Biomass for the subsequent production of biogas can be grown in an aquatic environment, cultivating algae and microalgae. In many scientific laboratories, for example, in the Laboratory of Renewable Energy Sources of Moscow State University. MV Lomonosov, are now engaged in the development of technologies for growing microalgae for the bioconversion of solar energy.

3) Wave energy
A wave power plant is an installation located in an aquatic environment, the purpose of which is to obtain electricity from the kinetic energy of waves.
Recently, scientists and designers have been paying close attention to the use of various types of energy from the World Ocean. The first tidal power plants were built. Methods are being developed for using the thermal energy of the ocean, associated, for example, with a significant temperature difference between the surface and deep layers of the ocean, reaching 20 ° C and more in tropical regions. At present, a significant amount of instrumental measurements of wind waves in the World Ocean has been accumulated. Based on these data, wave climatology identifies areas with the most intense and constant waves.

The first patent application for a wave power plant was filed in Paris in 1799. Already in 1890, the first attempt was made to use wave energy in practice, although the first 2.25 MW wave power plant entered commercial operation only in 2008 in the Agusador area ( Portugal) at a distance of 5 km from the coast (Figure 5.44). The power plant project belongs to the Scottish company Pelamis Wave Power, which in 2005 signed a contract with the Portuguese energy company Enersis to build a wave power plant. The contract value was 8 million euros. In 2009, a wave power plant was commissioned in the Orkney Islands. A 20 MW wave power plant is under construction in the UK. Some other coastal states are also building such power plants.
In most projects of wave power plants, it is assumed to use a two-stage conversion scheme. At the first stage, energy is transferred from the wave to the absorbing body and the problem of concentrating the wave energy is solved. At the second stage, the absorbed energy is converted into a form suitable for consumption. There are three main types of wave energy recovery projects. In the first, the method of increasing the concentration of wave energy and converting it into potential energy of water is used. In the second, a body with several degrees of freedom is located at the surface of the water. Wave forces acting on the body transfer part of the wave energy to it. The main disadvantage of this design is the vulnerability of the body under the influence of waves. In the third type of project, the energy absorbing system is under water. The transfer of wave energy occurs under the influence of wave pressure or speed.
In a number of wave installations, to increase efficiency, the density of wave energy is artificially increased. By changing the bottom topography in the coastal zone, you can concentrate sea waves like a lens that focuses light waves. If you focus waves from the coast with a length of several kilometers at a front of 500 m, then the wave height can reach 30 m.When it gets into special structures, the water rises to a height of 100 m.The energy of the raised water can be used to operate a hydroelectric power station located at ocean level ... A wave power plant of this type is used to provide electricity to the island of Mauritius, which does not have traditional energy sources.
A number of devices for the conversion of wave energy use different properties of wave movements: periodic changes in the level of the water surface, wave pressure or wave velocity. The percentage of use of wave energy reaches 40%. Electricity is transmitted to shore by cable. In Japan, an industrial prototype of such a system has been created, which has 9 turbines with a total capacity of 2 MW.
The force with which waves affect structures in the coastal zone reaches several tons per square meter. This forceful effect can also be used to transform wave energy.
Wave energy does not use fossil fuels, the cost of which is constantly increasing and the reserves are limited. Wave energy does not face the problem of environmental impact in an acute form. However, at present, the production of 1 kW of electricity at wave power plants is 5-10 times higher than at nuclear power plants or thermal power plants. In addition, if a significant part of the water area is covered by wave converters, this can lead to unpleasant environmental consequences, since waves play an important role in the gas exchange between the atmosphere and the ocean, in cleaning the sea surface and the near-surface layer of the air flow from pollution.
Therefore, wave energy should be considered only as an additional source of energy to traditional energy sources, which may be of importance only in some areas of the world.

4) Tidal power plants
In the coastal zone, tidal waves are manifested in periodic rise and fall of the level. In narrow areas, tides often appear as powerful currents. In some places, the height of the tide reaches a significant value - 12-20 m. The energy of tidal waves is enormous.

Man began to use the energy of the tides a long time ago. So, tidal mills were used in the 15th century in England, were widespread on the northeast coast of Canada in the 17th century.
To concentrate the water pressure at the station, the dam separates a part of the water area. The body of the dam houses hydro generators, culverts, and a station building. The amount of head depends on the level fluctuations on both sides of the dam. The fluctuations in the outer basin are determined by the local tide, the fluctuations in the inner basin are determined by the water flow during the operation of the station. Tidal stations refer to low-pressure hydraulic structures in which the water pressure is not more than 15-20 m.
The world's first tidal hydropower plant with a capacity of 320 MW was launched in 1966 at the mouth of the Rance River (France). The first tidal power plant in our country, with two 400 kW hydroelectric units, was built in Kislaya Bay on the Barents Sea in 1968. Several tidal power plants are being designed and already built in the Bay of Fundy, which is characterized by the highest tides in the world. The experience in the construction and operation of such stations has shown that they are economically justified, and the costs of their operation are much lower than during the operation of conventional hydroelectric power plants. The most developed market for electricity generated by waves and tides in the world is Scotland, which has the largest tidal turbines.

The use of tidal energy is mainly limited by the high cost of the structure. In addition, it turned out that tidal stations are characterized by a negative impact on the environment. The construction of the dam will increase the amplitude of the tide. Even a small increase in the amplitude of the tide will cause a significant change in the distribution of groundwater in the coastal zone, increase the flooding zone, disrupt the circulation of water masses, change the ice regime in the part of the basin behind the dam, etc.
The construction of the dam should also have important biological consequences. In the basin behind the dam, station operations will impact the littoral zone (the area between the highest flooding point at high tide and the lowest exposed at low tide). The dam may have harmful effects not only on local communities, but also on migratory species. For example, according to biologists, the construction of a dam in the Penzhinskaya Bay of the Sea of ​​Okhotsk will cause irreparable harm to the Okhotsk herring population. During the construction of dams in a temperate climate zone, the formation of a zone of hydrogen sulfide contamination, similar to those observed in bays and bays with natural rapids, is possible. The fiords of the Scandinavian Peninsula, which have a natural sill, are a classic example of such natural hydrogen sulfide contamination.

5) Gradient temperature energy
This method of obtaining energy is based on a temperature difference. Not too common. Through it, you can get a fairly large amount of energy at a low cost. The largest number of gradient-temperature power plants are located on the sea coast and use sea water for their work. Almost 70% of solar energy is absorbed by the world's oceans. The temperature difference between waters at a depth of hundreds of meters and waters on the ocean surface is a huge source of energy, which is estimated at 20-40 thousand TW, of which only 4 TW can be used.
Disadvantages: the release of a large amount of carbon dioxide, heating and lowering the pressure of deep waters, and cooling of surface waters. These processes negatively affect the climate, flora and fauna of the region.
Currently, a new concept of such power plants is being developed, which gives reason to expect efficient operation of the heat-and-power module not only in the warmest part of the tropical ocean, but also throughout the entire water area, where the average temperature gradient is about 17 ° C. The efficiency is expected to be nonzero even as temperature differences tend to zero. According to preliminary calculations, the costs of building such a hydroelectric power station are quite comparable with the costs of a traditional hydroelectric power station.

6) Wind energy
Humanity has been using wind energy for a long time. Sailing ships - the main form of transport that for centuries has provided communication between people of different continents, represent the most striking example of the use of wind energy.
Another well-known example of efficient use of wind energy is windmills. Windmills were widely used to pump water out of wells. At the end of the last century, a new stage in the use of wind turbines began - they began to be used to generate electricity. In the thirties of this century, millions of wind power generators with a capacity of about 1 kW were used in the countryside of Europe, America, Asia. With the development of central power supply, the spread of wind power generators has plummeted. With the rise in the cost of fossil fuels and the awareness of the environmental implications of its use, the hopes of many researchers have again begun to be associated with wind energy.
Indeed, the wind potential is enormous - about 2000 TW is the power of the wind flow in the atmosphere. The use of even a small part of this power would lead to the solution of the energy problems of mankind.
Wind energy does not consume fossil fuels, does not use water for cooling and does not cause thermal pollution of water bodies, does not pollute the atmosphere. And yet, wind power generators have a wide range of negative environmental impacts, revealed only after the wind renaissance began in the 1970s.
The main disadvantages of wind energy are low energy density, strong variability depending on weather conditions, and a pronounced geographical uneven distribution of wind energy. Typically, the operating range of wind speeds for large wind turbines is 5 to 15 m / s. At a wind speed of less than 5 m / s, the efficiency of the installation decreases; at a wind speed of more than 15 m / s, there is a high probability of breakage of the structure, primarily of the blades. The placement of generators at high altitudes (where the speed is higher) puts forward increased requirements for the strength of the structure of high-altitude masts, which must ensure the retention of the rotor, gearbox and generator under a powerful wind load. The development and creation of more reliable structures significantly increases the cost of wind turbines, although the cost of wind electricity is about 1.5-2 times lower than the cost of electricity obtained in photovoltaic converters.
Another important problem in the use of wind generators is the strong vibrations of their bearing parts, which are transmitted to the ground. A significant part of the sound energy falls on the infrasonic range, which is characterized by a negative effect on the human body and many animals.
Since the speed of rotation of the blades of wind generators is close to the synchronization frequency of television in a number of countries, the operation of wind generators interferes with the reception of television broadcasts within a radius of 1-2 km from the generator. Wind generators are also sources of radio interference. The rotation of the blades of wind generators is killing birds. Since usually wind turbines are located in large numbers in areas of strong winds (ridges, sea coast), they can lead to a disruption in the migration of migratory birds. The modulation of the wind flow by the blades creates some semblance of regular structures in the air that interfere with the orientation of the insects. In Belgium, it was found that this leads to a violation of the stability of the ecosystems of fields located in the zone of wind installations, in particular, a drop in yield is observed.
Finally, wind power requires large areas to house installations. Therefore, they try to locate wind turbine systems in a deserted area, which in turn increases the cost of energy transmission.
At present, a period of transition from research work in the field of wind energy to their widespread implementation has begun in the world. The pace of development of wind energy in countries such as the USA, Belgium, Great Britain, Norway, which have high wind energy potential, remain very high.

7) Geothermal energy

Geothermal energy is energy stored in hot water or steam from the interior of the Earth. In 1966, in Kamchatka, in the Pauzhetka River valley, the first geothermal thermal station with a capacity of 1.1 MW was launched in the USSR. In remote areas, the cost of energy obtained from geothermal plants is lower than the cost of energy obtained from imported fuels. Geothermal stations are successfully operating in a number of countries - Italy, Iceland, USA. The world's first geothermal power plant was built in 1904 in Italy. Geothermal energy began to be used in Iceland in 1944. However, interest and use of geothermal energy rose sharply in the 60s and 70s.

In the United States in California at the beginning of the 90s, there were about 30 stations with a total capacity of 2,400 MW. Steam for these stations was extracted from depths of 300 to 3000 m. In this state of the United States, over 30 years, the capacity of geothermal stations has increased almost 200 times. These are the rates of development of geothermal energy. The most accessible geothermal energy is in areas of increased volcanic activity and earthquakes. This localization is one of the disadvantages of geothermal energy. Geysers are a well-known form of hot water and steam entering the Earth's surface. According to the US Geological Survey, explored sources of geothermal energy could provide 5-6% of the current electricity consumption in the country. Estimation of promising sources gives a value of about 10 times higher. However, the exploitation of some of these sources is still unprofitable. Along with these resources that can be used to generate electricity, there is an even greater amount of water with a temperature of 90-1500C, which is suitable as a source of heat for heating. In the future, to extract energy from the bowels of the Earth, it is possible to use not only the reserves of hot water and steam, but also the heat of dry rocks (such areas of dry rocks with a temperature of about 3000C are found much more often than water-bearing hot rocks), as well as the energy of magma chambers, which in some areas are located at depths of several kilometers.
The most optimal form is dry steam. Direct use of a mixture of steam and water is not possible, because geothermal water usually contains a large amount of corrosive salts and water droplets in steam can damage the turbine. The most common form of energy supply is simply in the form of hot water, primarily for generating heat. This water can also be used to obtain a vapor of a working fluid, which has a lower boiling point than water. Since geothermal steam and water have a relatively low temperature and pressure, the efficiency of geothermal plants does not exceed 20%, which is significantly lower than nuclear (30%) and thermal ones operating on fossil fuels (40%).
The use of geothermal energy also has negative environmental consequences. The construction of geothermal stations disrupts the "work" of geysers. Geothermal plants use a large amount of cooling water to condense steam, therefore geothermal plants are sources of thermal pollution. With the same capacity as a thermal power plant or a nuclear power plant, a geothermal power plant consumes a much larger amount of water for cooling, because its efficiency is lower. The discharge of highly mineralized geothermal water into surface water bodies can disrupt their ecosystems. Geothermal water contains large quantities of hydrogen sulfide and radon, which causes radioactive pollution of the environment.

The world of modern energy is fundamental to the development of a variety of industries. Industrialized countries are distinguished by the rapid pace of energy development, which outstrips the pace of development of the sectoral industry.

In turn, energy is a serious source of adverse effects on humans and the environment. This influence affects the atmosphere through high oxygen consumption, emissions of gases, particulate matter and moisture.

Hydrosphere due to the consumption of water for the needs of energy, the creation of artificial reservoirs, discharges of liquid waste, heated and polluted waters. The lithosphere is also changing significantly due to the excessive consumption of fossil fuel resources, changes in landscapes, and the release of toxic substances.

Impact on water resources

Modern technologies differ in both advantages and disadvantages. For example, the amount of electricity produced depends on water resources, which can be depleted during a drought.

This plays a huge role for the country's energy complex. Energy and ecology- a dubious combination when it comes to the construction of dams, resettlement of residents, siltation of reservoirs, drying up of river beds, flooding of huge territories, significant cost of projects.

A change in the water level in rivers leads to the complete death of vegetation, dams become a serious obstacle to fish migration, multi-stage hydroelectric power plants have already turned rivers into lakes that grow into swamps. Russia receives no more than 20% of its energy from the use of hydro resources, and during the construction of only one hydroelectric power station, more than 6 million hectares are flooded. Thus, energy affects the environment, and this is an exchange of unequal losses for nature.

Exhaustion, pollution

As for the influence of TPP energy on the environment, it can be noted as the main factor, the release of harmful substances in the form of carbon monoxide, nitrogen compounds, lead and a significant amount of heat. 5 billion tons of coal are burned annually and more than three million tons of oil, which is accompanied by a gigantic release of heat into the Earth's atmosphere.

The current rates of coal consumption will lead to the inevitable depletion of the fossil in 150-200 years, oil in 40-50 years, gas, presumably, in 60. The full range of work on the extraction, transportation and combustion of this type of fuel is accompanied by processes that significantly affect pollution environment.

Associated with coal mining and water salinization. In addition, the pumped-out water contains radon and radium isotopes. And the atmosphere is polluted by the products of coal combustion in the form of sulfur oxides - 120 thousand tons, nitrogen oxides - 20 thousand tons, ash - 1500 tons, carbon monoxide - 7 million tons.

In addition, during combustion, more than 300 thousand tons of ash are formed, which includes 400 tons of toxic metals in the form of mercury, arsenic, lead and cadmium. The operation of a TPP can be compared, in terms of emissions of radioactive substances into the atmosphere, with the operation of a nuclear power plant of similar power.

The annual emissions of carbon oxides contribute to the rise in temperature on Earth, which can lead to quite predictable climatic changes.

The impact of energy on the environment when it comes to oil and gas has reached catastrophic and global proportions. Scientists argue that emissions from burning oil and coal annually affect human health in much the same way as the accident at the Chernobyl nuclear power plant. This "quiet Chernobyl" has consequences, the results of which are still invisible, but they purposefully and constantly destroy the environment.

How to get energy without harm to the environment

The sun is an inexhaustible source of heat. Among the existing traditional types of alternative energy (energy of waves, earth, wind, tides, geothermal energy, as well as energy from gas from landfills and manure on farms), the main type is solar energy.

The human world, constantly in search of energy, only recently drew attention to the source of energy abundance. The use of solar energy for the needs of industry at this stage is expensive.

But the downward trend in prices in recent years has significantly decreased and over the past five years has become two times lower than the initial one. Changing and improving technologies tomorrow can make solar energy affordable and unlimited.

Alternative energy and ecology: facts

• Renewable energy sources in Scotland account for one third of all energy generated.
• By 2027, the European Union plans to bring the share of alternative energy to 20%.
• Alternative energy contributes to job creation.
• Using cattle waste for processing into biogas will provide an opportunity to provide electricity to the inhabitants of the planet and reduce greenhouse gas emissions.
• Alternative energy is a more attractive industry for investors who prefer it over other types of fuel.

These and many other facts can provide our energy needs without harming the environment, which will make our nature and the world's population healthier.

The relationship between global and local environmental problems with energy is shown. The global criteria for these relationships have been established - the amount of consumed resources and the amount of greenhouse gases emitted. The quantitative characteristics of the types of energy carriers for these important indicators are given.

A qualitative and quantitative assessment of the environmental efficiency of various energy sources, including alternative and renewable ones, is given. It is shown that from the point of view of solving global environmental problems, nuclear energy has the greatest advantages.

Key words: environmental problems, energy - coal, gas, oil, solar, wind, nuclear, hydropower, qualitative and quantitative assessment of environmental efficiency.

The article describes the interrelation between global and local environmental issues and energy production. The author defines global criteria for these relationships which are the amounts of resources consumed and greenhouse gases emission. He also gives quantitative characteristics of the energy materials types with respect to these key indicators.

The article presents a qualitative and quantitative evaluation of the environmental efficiency of various types of energy sources including alternative and renewable ones. It is shown that the nuclear power has the greatest benefits in terms of solution of global environmental problems.

Keywords: environmental problems, power generation - coal, gas, oil, solar, wind, and nuclear, hydraulic power generation, qualitative and quantitative evaluation of environmental performance.

The ecologically conditioned threat to the existence of human civilization is officially recognized at the highest interstate level; scientific and technological progress has created the danger of an ecological catastrophe, and the very concept of "development" is called into question. There is an urgent need to revise the scale of human values.

The consumer attitude to nature has put it on the brink of survival. The dominant patterns of production and consumption lead to ecological devastation, an increasing risk to human life and health due to a decrease in the quality of the environment. The foundations of global security are under threat.

As follows from the report of the United Nations Commission on the Environment (UNEP), the forecast of human development until 2032 is disappointing. Under the influence of human activity, irreversible changes will occur on the planet. More than 70% of the earth's surface will be deformed in one way or another, more than 1/4 of all species of flora and fauna will be irretrievably lost, safe air, clean drinking water, undisturbed landscapes will become an irreplaceable deficit, nature's ability to recover from anthropogenic impact will decrease.

It is the high quality of the natural environment that is the main wealth of mankind and an unconditional value category, the essence global environmental interests. According to the WHO, today 80% of all diseases in the world arise from the consumption of poor-quality drinking water, and according to the IAEA, 5 million people die annually from diseases associated with the consumption of contaminated and poor-quality water. Water may well become almost the main reason for future armed conflicts, the same as now arise over oil.

Even the most superficial statistics related to the ecological state of the territory of Russia gives disappointing forecasts: for example, today more than a third of the urban population of the Russian Federation lives in areas where monitoring of atmospheric pollution is not carried out, and more than half - in cities with high and very high the level of air pollution.

Russia, along with the entire planet, is experiencing serious environmental problems - the average air temperature rises, permafrost recedes, and various manifestations of climatic instability are observed. The problem of global warming is increasingly accompanied by problems of environmental impacts caused by increased extreme weather conditions.

Environmental problems, depending on the scale of the impact of human economic activity on the environment, are usually divided into global and local. Global environmental problems are directly related to local environmental problems (Fig. 1).

Renewable and non-renewable sources exist to meet energy demand. The sun, wind, hydropower, tides and some other sources of energy are called renewable, since their use by humans practically does not change their reserves. Coal, oil, gas, peat, uranium are classified as non-renewable energy sources, and during processing they are lost irretrievably.

At the same time, this classification is rather arbitrary, for example, the use of uranium in a closed fuel cycle is more likely to be of a renewable type.

Rice. 1. Interrelation of global and local environmental problems

Global environmental problems are closely related primarily to the economic situation in specific countries, the main indicators of which are GDP per capita, as well as energy production and consumption (Table 1).

Table 1

The main energy characteristics of the countries of the world -

main consumers of primary energy

* - for 2010, except for electricity consumption in China and India (for 2009) [Russia ... 2012].

** - for 2012, except for the capacity of power plants in Japan, India (2009) and the USA (2010).

From table. 1 shows that energy consumption in developed countries is 11–17 times higher than in developing countries (for example, China and India).

If all countries of the world in the next 15–20 years reach the level of energy consumption of the USA or at least "economical" Japan, then the total energy consumption will increase in accordance with the population size, that is, almost 15 times. Is the global energy sector ready for such a “great leap forward”? Of course not. There is simply not so much fossil fuel on the planet. Therefore, we can draw the following conclusion: the development of energy should go towards the use of new powerful energy sources without burning fossil fuel.

The trend towards the use of electrical energy is evident. But this is only an intermediate form, that is, in order to produce energy, you need to have a primary sufficiently powerful source.

Exhaustible energy resources - oil, coal and gas along with uranium (nuclear power) - will remain the main sources of energy in the coming decades (Fig. 2), and the share of energy production based on the use of hydrocarbons will continue to be the largest. Nevertheless, the limited reserves of oil and gas are evident. The prospect of their active use is visible only for several decades. During this time, the power generating facilities using oil and gas must be replaced by others.

Rice. 2. Contribution of various types of energy carriers to the production of electricity in the world

The main problem of interest to humanity is ensuring environmental safety. The concept of "environmental safety" is defined in the law "On environmental protection": "Environmental safety is the state of protection of the natural environment and vital human interests from the possible negative impact of economic and other activities, natural and man-made emergencies, their consequences" [Federal ... 2002].

Threats to environmental safety:

Destruction of the ozone layer;

Changing of the climate;

Transboundary environmental impact;

Degradation of ecosystems;

Loss of biological diversity;

Decrease in forest cover;

Degradation of agricultural land;

Depletion and scarcity of natural resources;

Chemical, physical, radiation pollution of the environment.

Global environmental problems are closely related to global energy problems (Fig. 3).

The link between global environmental and energy issues is especially visible when comparing two indicators:

1) the required mass of withdrawn resources to obtain a unit of energy;

2) global impact on nature through the release of greenhouse gases.

Table 2 shows the main characteristics of various methods of generating electricity in terms of two global indicators: greenhouse gas emissions and power release per unit mass, indicating the efficiency of using the internal energy of matter, that is, nuclear and thermonuclear energy. This, in fact, is the basis for the existence of the solar system, the energy in which exists thanks to two reactors: nuclear (inside the Earth) and thermonuclear (on the Sun).

table 2

Global Efficiency of Various Power Generation Methods

The solution to the problem of energy supply could be a full-fledged mastery of the energy of thermonuclear fusion. However, studies of recent years have shown that at the current level of development of technology and technology on the path of full-scale use of thermonuclear energy, there are a number of technical problems that scientists have been solving for the past 50 years without any significant success.

Thus, among the existing alternative replacement possibilities, it is only modern technologies of fuel and nuclear energy that will really cover the growing needs of mankind for energy for the next several hundred years.

The most interesting from the point of view of the impact on nature and human health are coal and nuclear energy, since only these two types of energy carriers have reserves for a sufficiently long period. So, according to V.G. Rodionov, coal will last 420 years, while by 2030 only 1/5 of the available reserves will remain hydrocarbons, that is, they can be basically exhausted in the next 30 years. At the same time, the reserves of uranium, taking into account the involvement of the 238 isotope in fast reactors, will last for thousands of years.

Coal. Air emissions from coal plants have caused the so-called acid rain, which destroys vegetation, soil, water bodies and, above all, human health. To estimate the amount of acid rain falling, it is enough to imagine that one thermal power plant with a capacity of 1000 MW, operating on coal with a sulfur content of about 3.5%, despite the use of cleaning agents, emits about 140 thousand tons of sulfurous anhydride into the atmosphere per year, from which produces about 280 thousand tons of sulfuric acid. The wind raises ash from the surfaces of ash dumps, forming dust storms, the annual volume of ash and slag waste from the CIS TPPs currently exceeds 120 million tons.

The list of the main substances emitted into the environment as a result of the operation of coal-fired power plants, as well as the main environmental consequences, is presented in Table. 3, the potential impact of emissions from coal plants on the human body is shown in Fig. 3.

Table 3

Emissions of hazardous substances from coal combustion and main environmental impacts

In the process of burning coal, radioactive contamination of the environment occurs, the radionuclides contained in it (238 U, 210 Pb, 40 K, 210 Po, 226 Ra, 228 Ra, 230 Th, etc.) are released into the atmosphere and are concentrated in ash, the release of radioactive substances per unit of energy received at coal-fired power plants is more than at nuclear power plants.

Rice. 3. The impact of emissions from coal plants on the human body

The cleanest fossil fuel - natural gas . Let's dwell on such a source as shale gas .

The conducted research revealed 5 main environmental problems of shale gas production:

1) pollution of aquifers with highly toxic substances and surface water bodies with wastewater;

2) methane emissions into the atmosphere;

3) an increase in the radioactive background in the areas of production;

4) an increase in the likelihood of earthquakes;

5) withdrawal from circulation of significant land and water resources.

The main environmental problems arising from the production and use of oil as an energy resource are associated with:

Chemical pollution of groundwater during production, chemical and thermal pollution of surface waters, formation of an oil slick;

Violation of the habitats of fauna and flora growth;

Contamination and degradation of the soil cover;

Significant water intake.

Nuclear power does not consume oxygen, does not emit harmful chemicals into the atmosphere and water bodies, it significantly saves the consumption of fossil fuel, the reserves of which are quite limited. In particular, in the five most developed countries of the world, nuclear power can save up to 440 million tons of coal per year (in Russia - 65.3 million tons), 350 million tons of oil (in Russia - 40.3 million tons), up to 280 billion m3 3 gas (in Russia - 36.8 billion cubic meters), to prevent the combustion of over 450 million tons of oxygen (in Russia - 36 million tons), to preserve land space on an area of ​​70 thousand hectares (in Russia - 11 thousand hectares). France is called an ecologically clean region of Europe, where electricity generation at nuclear power plants exceeded 70% of the total.

Of all types of renewable energy sources, only hydropower currently makes a significant contribution to global electricity production (17%). In most industrialized countries, only a small amount of hydropower potential remains unused today, which is primarily due to the need to alienate significant territories when organizing hydroelectric power plants. Main environmental impacts hydropower:

Flooding of agricultural land and settlements;

Violation of the water balance, which leads to a change in the conditions for the existence of flora and fauna;

Climatic consequences (change in heat balance, increase in precipitation, wind speed, cloud cover, etc.);

Silting up of the reservoir and erosion of the banks, deterioration of self-purification of running waters and a decrease in the oxygen content, the free movement of fish is impeded;

Hydropower facilities pose the potential for major disasters.

Wind power also has a negative impact on the environment:

Alienation of large land areas (for example, for the current level of electricity production in France using wind energy, it will take about 20 thousand km 2 of land - 4% of the country's territory);

Wind power is an unregulated source of energy;

Noise impacts (when using an installation with a capacity of 2-3 MW, it becomes necessary to turn it off at night);

Interference to air traffic and to radio and television broadcasting, disruption of bird migration routes (an installation with a capacity of 2-3 MW should have a wind wheel diameter of 100 m);

Local climatic changes due to disruption of the natural circulation of air flows;

Danger to migratory birds and insects;

Change in traditional shipping, adverse impact on marine animals (when placing wind turbines in the aquatic environment);

Landscape incompatibility, unattractiveness, visual discomfort.

Solar power plants(SES) are effective only for areas with a high level of insolation. In the middle zone of the European part of Russia, the intensity of solar radiation is 150 W / m2, which is 1000 times less than the heat fluxes in the boilers of TPPs. When using SPP, a number of environmental problems arise:

Alienation of large land areas, their possible degradation (only for SPP of 1 GW (e) in the middle zone of the European part of Russia at 10% efficiency, a minimum area of ​​67 km 2 is required);

Dimming large areas with solar concentrators;

Large material consumption (time and human resources consumption is 500 times more than in traditional energy);

Possible leaks of working fluids containing chlorates and nitrites;

Overheating and ignition of systems, contamination of products with toxic substances when using solar systems in agriculture;

Changes in heat balance, humidity, wind direction in the area of ​​the station;

The impact of space solar power plants on the climate;

Energy transfer to the Earth in the form of microwave radiation, which is dangerous for living organisms and humans.

Main environmental impacts bioenergy:

Emissions of particulate matter, carcinogenic and toxic substances, carbon monoxide, biogas, bio-alcohol;

Heat emission, change in heat balance;

Depletion of soil organic matter, depletion and erosion of soil (for the production of biogas from manure to generate 1000 MW of electricity, 80 million pigs or 800 million birds are required on an area of ​​80–100 km 2);

Explosion hazard (biogas electrical installation must be controlled and maintained in good working order in accordance with the instructions);

Large amount of waste in the form of by-products (wash water, distillation residues).

The assessment of the environmental efficiency of the impact of energy generation on the environment, carried out in this work on the basis of a scoring of various methods of generating electricity, made it possible to conduct a comparative analysis of the environmental efficiency of electricity production using various types of energy resources according to seven important indicators: the volume of greenhouse gas emissions, the volume of emissions of harmful substances in atmosphere, volume of discharges into water sources, waste generation, alienation of land resources, release of radioactive substances into the environment and risk to people (Table 4).

Table 4

Comparative indicators of environmental performance

different ways of producing energy

For a comprehensive assessment of the impact on the environment of all factors taken into account, the authors have developed a total integrated indicator of the impact on the environment. When calculating it, seven of the most important environmental indicators were assessed using a 10-point system: 10 points - the most harmful impact (in actual value) and 0 points - no impact.

The calculated values ​​of the total complex indicator of environmental impact are shown in Fig. 4 and 5.

Calculations of environmental impact indicators have shown that coal takes the 1st place in terms of greenhouse gas emissions; gas and oil are approximately 28% lower in terms of exposure; hydropower, solar, wind and nuclear energy are very low, that is, there is only a concomitant emission of greenhouse gases during power generation.

Rice. 4. Comparative indicators of the environmental efficiency of various methods of energy production

Rice. 5. The total complex indicator of the harmful impact on the environment and humans

When considering the impact on the environment in terms of emissions of harmful substances, it was found that the largest emissions are typical for coal, half the emissions for oil and gas, but an approximately comparable volume of emissions is typical for the production and disposal of solar panels. A similar situation is observed with regard to waste.

The impact on the environment in terms of alienation of land resources is most typical for hydro and solar energy.

It would seem that nuclear power should lead in the release of radioactive substances into the environment, but in reality it turns out that due to the highest perfection of the processes in it, the actual emissions of radioactive substances into the environment in the normal mode are half as much as when burning coal.

Thus, based on a comparison of the environmental impact of various types of energy generation, presented in Fig. 5, it can be concluded that from the point of view of both global and local environmental problems, nuclear power looks preferable in all respects.

Literature

Makarov A.A. 2009. No. 2 (28). S. 4-12.

Rodionov V.G. Power Engineering: Problems of the Present and Possibilities of the Future. M.: ENAS, 2010.

Fortov V.E., Makarov A.A. Directions of innovative development of energy in the world and in Russia // Uspekhi fizicheskikh nauk. 2009.Vol. 179.No. 12.P. 1337–1353.

Russia and the countries of the world: stat. Sat. M.: Rosstat, 2012.

BP Statistical Review of World Energy June 2012. N. p. : Pureprint Group Limited, 2012.

Grachev V. A., Lobkovsky V. A. Possible Environmental Impacts of Shale Gas Production in Europe Based on the International Practices of Fracking Technology Utilization // Biosciences Biotechnology Research Asia. 2015. Vol. 12.No. 1. Pp. 253-261.

International Energy Agency. Energy Technology Perspectives. Paris: OECD / IEA, 2008.

Central Intelligence Agency. The World Factbook: [site]. URL: https://www.cia.gov/ library / publications / the-world-factbook /.

Energy is one of the most important conditions for the existence of a biosystem. Until recently, that is, approximately 3.5 billion years, the Earth's biosphere had enough energy from the Sun. And the only one who lacks her on our planet is a man. He needs additional energy not as a living organism, but in connection with the provision of his production and economic activities and household needs. For these purposes, humanity produces two types of energy: thermal and electrical. In their production, together in the energy sector, several related branches of economic activity are involved. Therefore, the environmental problems of the energy sector are not problems of one direction of human activity, but of a whole complex. They are multifaceted and numerous and arise at all stages of production from mining to the supply of energy to the final consumer.

Currently, energy is generated from two sources: renewable and non-renewable. The first includes the energy of the sun, wind and water. In this case, production is ineffective, dependent on external conditions and is associated with significant costs. Non-renewable sources include all types of minerals, the internal chemical energy of which can be converted. These are: wood, peat, coal, oil, gas and their derivatives. The splitting of the atom in the middle of the last century made it possible to obtain the energy arising in the course of nuclear reactions. This is how nuclear power emerged, which stands somewhat apart from the others.

Numerous thermal, hydro and power plants, complexes that simultaneously produce thermal and electrical energy are engaged in the development. These stations vary in power. Most of the stations were built based on a production capacity of 1000 MW. But there are also small stations that provide energy to small consumers, up to private households. Nuclear power plants have an enormous capacity of up to 8,200 MW.

The environmental problems of the energy sector start with the extraction of natural resources. The development of peatlands and deforestation, coal mines and oil and gas fields are, above all, the devastation of nature. The resources created by nature over millions of years are taken out of their places of deposits and cannot be replenished in the future. During the development and after their completion, the territories, as a rule, remain abandoned. Soil reclamation is not carried out, trees are not planted in place of the felled ones. Ecosystems degrade and die.

The transportation of extracted minerals to the places of their application is carried out along natural transport corridors - rivers, seas and oceans, or along specially created pipelines, railways and transport highways. Accidents, spills, emissions, flooding, blockages and much more pollute the territories through which transportation takes place.

Stations, their types and problems

The environmental problems of modern energy are also the requirements for technical and construction standards for the location of power and heat generating stations.

Hydroelectric power stations. The ability to generate energy using water creates the need to create additional hydraulic structures. Cascades of dams and reservoirs erected on rivers lead to disruption of their water exchange. The need to create reservoirs for the operation of hydroelectric power plants, not only leads to flooding of significant areas, it also significantly affects the water level of the river and most of its tributaries. The level of rivers, as a rule, rises, but the tributaries become shallow and, like river arteries, disappear. Regulation of the water level also has a negative impact on the ecosystem of the water basin. A rapid discharge and lowering of the level, and then a collection of water, leads to the destruction of the soil, washing away of the fertile layer, and the death of fish spawning grounds. The most illustrative example of the destructive impact of hydraulic structures on a water basin and the surrounding nature is the Caspian Sea. After the commissioning of the dam complex, the water level in the sea changed, the oxygen exchange changed, and the supply of nutrients decreased. The negative consequences became so threatening for the existence of the marine biosystem as a whole that it was necessary to make adjustments to the dam design.

Reservoirs, created in the area of ​​thermal and power plants, serve for the discharge of process waters. By themselves, these drains do not have significant pollution, but they pose another danger to the environment, they have an elevated temperature. As a result, not only the temperature regime of the water body changes, but also the climatic conditions of the adjacent territory. Changes and mutations occur in plants and animals.

Thermal and power plants operate on different types of fuel: solid, liquid or gaseous. Regardless of what type of fuel the stations use, the stations burn thousands of cubic meters of oxygen and emit into the atmosphere no less amount of ash, combustion products and gases that contain pollutants. These substances enter the soil and water not only directly near the station, but spread through the air over considerable distances.

Atomic

The splitting of the atom has given humanity additional energy resources and opportunities, and with it new problems. The environmental problems of nuclear power are of a specific nature. This fairly new industry has problems inherent in this entire area. In the process of extracting raw materials, the ecology of the places of its occurrence is destroyed. The reservoirs near the stations, intended for draining the cooling water, also form a microclimate unusual for this natural zone. There are also positive aspects - there are practically no emissions typical of plants operating on the principle of burning raw materials. Nuclear energy environmental problems are deferred. They are associated with the production of fuel for these stations and the storage of spent.

The main argument in favor of expanding nuclear energy production is its low cost. In addition, states that do not have the necessary raw materials can locate nuclear power plants on their territory. Atomic is the only way out for countries that do not have raw materials for other types of stations in their depths. But is nuclear energy really that cheap? If we add to the cost of raw materials, the station and the production process the cost of disposal and storage of spent fuel, the funds spent on the elimination of various kinds of breakdowns, accidents and disasters, as well as their consequences. The amounts required to treat the participants in the elimination of these accidents, their children, contaminated nature, and so on.

The first nuclear power plant was built in the USSR in 1954. After 32 years, an accident occurred at the Chernobyl station, and another 25 years later - at the Fukushima station. We can say that there are only two accidents in more than 60 years, or we can say that accidents happen every 25-30 years. Regardless of how to keep statistics, it takes from 30 to 1000 years in each case to restore the natural environment affected by radiation. The environmental problems of nuclear energy were seriously paid attention only after 1986, when an accident occurred at the Chernobyl nuclear power plant. This reaction was similar to panic. Many countries of the world have completely abandoned the construction of nuclear reactors on their territory. But the economy puts forward its arguments, and the current safety of nuclear production is several times higher than other types of energy.

The environmental problems of nuclear power are not only problems of the "peaceful" atom. It is also the navy, including the military in the first place, and weapons. What surprises can be expected from this side - no one knows?

Video - Nuclear Power and Its Alternative

21. Environmental problems of energy and ways to solve them.

At present, energy needs are met mainly from three types of energy resources: fossil fuel, water and the atomic nucleus. The energy of water and atomic energy is used by humans after converting it into electrical energy. At the same time, a significant amount of energy contained in fossil fuel is used in the form of heat and only part of it is converted into electrical energy. However, in both cases, the release of energy from organic fuel is associated with its combustion, and, consequently, with the entry of combustion products into the environment.

Environmental problems of heat power engineering

The impact of thermal power plants on the environment largely depends on the type of fuel burned.

Solid fuel... When solid fuel is burned, fly ash with particles of unburned fuel, sulfuric and sulfuric anhydrides, nitrogen oxides, a certain amount of fluoride compounds, as well as gaseous products of incomplete fuel combustion, enter the atmosphere. In some cases, fly ash contains, in addition to non-toxic components, more harmful impurities. Thus, the ash of Donetsk anthracites contains insignificant amounts of arsenic, and the ash of the Ekibastuz and some other deposits contains free silicon dioxide, and the ash of shale and coals of the Kansk-Achinsk basin contains free calcium oxide. Solid fuels include coal and peat.

Liquid fuel... When burning liquid fuel (fuel oil) with flue gases, the following enter the atmospheric air: sulfuric and sulfuric anhydrides, nitrogen oxides, vanadium compounds, sodium salts, as well as substances removed from the surface of boilers during cleaning. From an environmental point of view, liquid fuel is more "hygienic". At the same time, the problem of ash dumps, which occupy large areas, exclude their useful use, and are a source of constant atmospheric pollution in the station area due to the carryover of part of the ash with the winds, completely disappears. There is no fly ash in the combustion products of liquid fuels. Liquid fuels include natural gas (???).

Coal, oil and oil products, natural gas and, less often, wood and peat are used as fuel at thermal power plants. The main components of combustible materials are carbon, hydrogen and oxygen, sulfur and nitrogen are contained in smaller amounts, there are also traces of metals and their compounds (most often oxides and sulfides).

In heat power engineering, the source of massive atmospheric emissions and large-tonnage solid waste are thermal power plants, enterprises and steam power facilities, i.e., any enterprises whose work is associated with fuel combustion.

Along with gaseous emissions, the thermal power industry produces huge masses of solid waste; these include ash and slag.

Waste from coal preparation plants contains 55-60% SiO2, 22-26% Al2O3, 5-12% Fe2O3, 0.5-1% CaO, 4-4.5% K2O and Na2O and up to 5% C. They go to dumps, which generate dust, smoke and sharply worsen the state of the atmosphere and surrounding areas.

A coal-fired power plant requires 3.6 million tons of coal, 150 m3 of water and about 30 billion m3 of air annually. These figures do not take into account the environmental disturbances associated with the extraction and transportation of coal.

Considering that such a power plant has been actively operating for several decades, then its effect can be compared with the effect of a volcano. But if the latter usually throws out products of volcanism in large quantities at one time, then the power plant does it all the time.

Pollution and waste of energy facilities in the form of gas, liquid and solid phases are distributed into two streams: one causes global changes, and the other - regional and local. The situation is the same in other sectors of the economy, but energy and fossil fuel combustion remain a source of major global pollutants. They enter the atmosphere, and due to their accumulation, the concentration of small gas constituents of the atmosphere, including greenhouse gases, changes. In the atmosphere, gases appeared that were previously practically absent in it - chlorofluorocarbons. These are global pollutants with a high greenhouse effect and at the same time participating in the destruction of the ozone screen of the stratosphere.

Thus, it should be noted that at the present stage, thermal power plants emit into the atmosphere about 20% of the total amount of all hazardous industrial waste. They significantly affect the environment of the area where they are located and the state of the biosphere as a whole. The most harmful are condensing power plants operating on low-grade fuels.

Wastewater from TPPs and storm water from their territories, contaminated with waste from technological cycles of power plants and containing vanadium, nickel, fluorine, phenols and oil products, when discharged into water bodies, can affect the quality of water and aquatic organisms. A change in the chemical composition of certain substances leads to a violation of the habitat conditions established in the reservoir and affects the species composition and number of aquatic organisms and bacteria and, ultimately, can lead to disturbances in the processes of self-purification of water bodies from pollution and to a deterioration in their sanitary state.

The so-called thermal pollution of water bodies with various violations of their condition is also dangerous. Thermal power plants generate energy using turbines driven by heated steam. During the operation of turbines, it is necessary to cool the waste steam with water, therefore, a stream of water, usually heated by 8-12 ° C and discharged into the reservoir, continuously leaves the power station. Large thermal power plants require large amounts of water. They discharge 80-90 m3 / s of water in a heated state. This means that a powerful stream of warm water of about the same scale as the Moskva River continuously enters the reservoir.

The heating zone, formed at the confluence of the warm "river", is a kind of section of the reservoir, in which the temperature is maximum at the point of the spillway and decreases with distance from it. Heating zones of large thermal power plants cover an area of ​​several tens of square kilometers. In winter, polynyas are formed in the heating zone (in the northern and middle latitudes). During the summer months, the temperatures in the heating zones depend on the natural temperature of the intake water. If the water temperature in the reservoir is 20 ° C, then in the heating zone it can reach 28-32 ° C.

As a result of an increase in temperatures in the reservoir and a violation of their natural hydrothermal regime, the processes of "blooming" of water intensify, the ability of gases to dissolve in water decreases, the physical properties of water change, all chemical and biological processes occurring in it are accelerated, etc. In the heating zone the transparency of water decreases, the pH increases, and the rate of decomposition of easily oxidized substances increases. The rate of photosynthesis in such water is noticeably reduced.

Environmental problems of hydropower

Despite the relative cheapness of energy obtained from hydro resources, their share in the energy balance is gradually decreasing. This is due to both the depletion of the cheapest resources and the large territorial capacity of lowland reservoirs. It is believed that in the future, the world energy production of hydroelectric power plants will not exceed 5% of the total.

One of the most important reasons for the decrease in the share of energy received at hydroelectric power plants is the powerful impact of all stages of construction and operation of hydroelectric facilities on the environment.

According to various studies, one of the most important impacts of hydropower on the environment is the alienation of significant areas of fertile (floodplain) lands for reservoirs. In Russia, where no more than 20% of electricity is produced through the use of hydro resources, at least 6 million hectares of land were flooded during the construction of a hydroelectric power station. In their place, natural ecosystems have been destroyed.

Large areas of land near reservoirs experience flooding as a result of rising groundwater levels. These lands tend to be classified as wetlands. In flat conditions, flooded land can account for 10% or more of flooded land. The destruction of lands and their characteristic ecosystems also occurs as a result of their destruction by water (abrasion) during the formation of the coastline. Abrasion processes usually last for decades, resulting in the processing of large masses of soil, water pollution, siltation of reservoirs. Thus, the construction of reservoirs is associated with a sharp violation of the hydrological regime of rivers, their characteristic ecosystems and the species composition of hydrobionts.

In reservoirs, the warming up of water sharply increases, which intensifies the loss of oxygen by them and other processes caused by thermal pollution. The latter, together with the accumulation of nutrients, creates conditions for the overgrowth of water bodies and the intensive development of algae, including poisonous blue-green algae. For these reasons, as well as due to the slow renewal of waters, their ability to self-purify sharply decreases.

Deterioration in water quality leads to the death of many of its inhabitants. The morbidity of the fish stock is increasing, especially the attack by helminths. The taste of the inhabitants of the aquatic environment decreases.

The migration routes of fish are disrupted, forage lands, spawning grounds, etc. are being destroyed. The Volga has largely lost its significance as a spawning ground for sturgeon in the Caspian after the construction of a cascade of hydroelectric power stations on it.

Ultimately, river systems blocked by reservoirs turn from transit to transit-accumulative. In addition to biogenic substances, heavy metals, radioactive elements and many pesticides with a long life span are accumulated here. Accumulation products make it problematic to use the territories occupied by reservoirs after their liquidation.

Reservoirs have a significant impact on atmospheric processes. For example, in arid (arid) regions, evaporation from the surface of reservoirs exceeds evaporation from an equal land surface by tens of times.

A decrease in air temperature and an increase in foggy phenomena are associated with increased evaporation. The difference in heat balances of reservoirs and adjacent land leads to the formation of local winds such as breezes. These, as well as other phenomena, result in a change in ecosystems (not always positive), a change in weather. In some cases, it is necessary to change the direction of agriculture in the reservoir zone. For example, in the southern regions of our country, some heat-loving crops (melons) do not have time to ripen, the incidence of plants increases, and the quality of products deteriorates.

The environmental costs of hydroelectric construction are noticeably lower in mountainous areas, where reservoirs are usually small in area. However, in earthquake-prone mountainous areas, reservoirs can provoke earthquakes. The likelihood of landslides and the likelihood of disasters as a result of the possible destruction of dams increases.

Due to the specificity of the technology for using water energy, hydropower facilities transform natural processes for a very long time. For example, a reservoir of a hydroelectric power station (or a system of reservoirs in the case of a cascade of hydroelectric power plants) can exist for tens and hundreds of years, while a technogenic object arises in the place of a natural watercourse with artificial regulation of natural processes - a natural-technical system (PTS).

Considering the impact of HPPs on the environment, one should nevertheless note the life-saving function of HPPs. Thus, the generation of each billion kWh of electricity at hydroelectric power plants instead of thermal power plants leads to a decrease in the mortality rate of the population by 100-226 people / year.

Nuclear power problems

At present, nuclear power can be considered as the most promising. This is due to both the relatively large reserves of nuclear fuel and the gentle impact on the environment. The advantages also include the possibility of building a nuclear power plant without being tied to resource deposits, since their transportation does not require significant costs due to small volumes. Suffice it to say that 0.5 kg of nuclear fuel can generate the same amount of energy as burning 1000 tons of coal.

Many years of experience in operating nuclear power plants in all countries shows that they do not have a noticeable impact on the environment. By 1998, the average operating time of a nuclear power plant was 20 years. The reliability, safety and economic efficiency of nuclear power plants is based not only on strict regulation of the NPP operation process, but also on minimizing the NPP's impact on the environment to an absolute minimum.

During normal operation of a nuclear power plant, emissions of radioactive elements into the environment are extremely insignificant. On average, they are 2-4 times less than from TPPs of the same capacity.

Before the Chernobyl disaster in our country, no industry had a lower level of industrial injuries than nuclear power plants. 30 years before the tragedy, 17 people died in accidents, and even then not for radiation reasons. After 1986, the main environmental hazard of nuclear power plants began to be associated with the possibility of an accident. Although the likelihood of them at modern nuclear power plants is small, but it is not excluded.

Until recently, the main environmental problems of nuclear power plants were associated with the disposal of spent fuel, as well as with the liquidation of the nuclear power plants themselves after the end of the permissible operating life. There is evidence that the cost of such liquidation works ranges from 1/6 to 1/3 of the cost of the NPPs themselves. In general, the following impacts of nuclear power plants on the environment can be named: 1 - destruction of ecosystems and their elements (soils, grounds, aquiferous structures, etc.) in places where ores are mined (especially with an open method); 2 - seizure of land for the construction of the NPP themselves; 3 - withdrawal of significant volumes of water from various sources and discharge of heated water; 4 - radioactive contamination of the atmosphere, waters and soils during the extraction and transportation of raw materials, as well as during the operation of nuclear power plants, storage and processing of waste, and their burials is not excluded.

There is no doubt that in the near future, thermal energy will remain dominant in the energy balance of the world and individual countries. There is a high likelihood of an increase in the share of coal and other less clean fuels in energy production. Some ways and methods of their use can significantly reduce the negative impact on the environment. These methods are based mainly on the improvement of technologies for the preparation of fuel and the capture of hazardous waste. Among them:

1. Use and improvement of cleaning devices.

2. Reducing the release of sulfur compounds into the atmosphere by means of preliminary desulfurization (desulfurization) of coals and other types of fuel (oil, gas, oil shale) by chemical or physical methods.

3. Large and real possibilities of reducing or stabilizing the flow of pollution into the environment are associated with energy savings.

4. Opportunities for saving energy in everyday life and at work by improving the insulating properties of buildings are no less significant. It is extremely wasteful to use electrical energy to generate heat. Therefore, direct combustion of fuel to generate heat, especially gas, is much more rational than converting it into electricity and then back into heat.

5. Fuel efficiency is also noticeably increased when it is used instead of thermal power plants at thermal power plants. + Use of alternative energy

6. Use of alternative energy sources whenever possible.