The sun plays an exceptional role in the life of the Earth. The entire organic world of our planet owes its existence to the Sun. The sun is not only a source of light and heat, but also the original source of many other types of energy (oil, coal, water, wind).

Solar constant - the amount of solar energy arriving on a surface of 1 square meter, deployed perpendicular to the sun's rays in space.

The sun is our star. By studying the Sun, we learn about many phenomena and processes that occur on other stars and are inaccessible to direct observation due to the enormous distances that separate us from the stars.

The sun is the main source of energy on earth and the root cause that created most of the other energy resources of our planet, such as coal reserves, oil, gas, wind and falling water energy, electrical energy, etc.

The energy of the Sun, which is mainly released in the form of radiant energy, is so great that it is difficult to even imagine. Suffice it to say that only one two-billionth part of this energy reaches the Earth, but it is about 2.5 * 10 18 cal./min. Compared to this, all other sources of energy, both external (radiation from the moon, stars, cosmic rays) and internal (internal heat of the Earth, radioactive radiation, reserves of coal, oil, etc.) are negligibly small.

The Sun is the closest star to us, which is a huge luminous ball of gas, the diameter of which is approximately 109 times the diameter of the Earth, and its volume is approximately 1 million 300 thousand times greater than the volume of the Earth. The average density of the Sun is about 0.25 that of our planet.

Since the sun is not a solid ball, but a gaseous ball, we should talk about its dimensions conditionally, meaning by them the dimensions of the solar disk visible from the Earth.

The interior of the sun is not observable. It is a kind of atomic cauldron of gigantic proportions, where complex nuclear reactions take place under a pressure of about 100 billion atmospheres, during which hydrogen is converted into helium. They are the source of the sun's energy. The temperature inside the sun is estimated at 16 million degrees.

Trophic chains. Basic concepts, elements.

1. Definition of the concepts “food chain”, “trophic level”, “consumers”. Within an ecosystem, energy-containing organic substances are created by autotrophic organisms and serve as food (a source of matter and energy) for heterotrophs. Example: an animal eats plants, this animal in turn can be eaten by another animal, and energy can also be transferred through a number of organisms - each subsequent one feeds on the previous one, which supplies it with raw materials and energy. This sequence is called food chain, and each of its links is trophic level(Greek trophos - food). Consumers: primary - feed on primary producers, i.e. these are herbivores; secondary cons. - feed on herbivores, so these are ude carnivores, as well as tertiary cons., eating cons. second order.

2 . Living organisms that are part of the biocenosis in an ecosystem are not the same in terms of the specificity of their assimilation of matter and energy. Unlike plants and bacteria, animals are not capable of photo- and chemosynthesis reactions, but are forced to use solar anergy indirectly - through organic matter created by photo- and chemosynthetics. Thus, in the biocenosis, a chain of sequential transfer of matter and its equivalent energy from one organism to another is formed, or the so-called trophic chain (from the Greek “trophe” - I eat).

Since plants build their organisms without intermediaries, they are called self-feeding, or autotrophs. Since being autotrophs, they create primary organic matter from inorganic matter, they are producers. Organisms that cannot build their own substance from mineral components use organic matter created by autotrophs, consuming them as food. They are called heterotrophs, which means “fed by others,” as well as consumers (from the Latin “consumo” - I consume). Carnivores use animal proteins with a specific set of amino acids. They are also consumers, but, unlike herbivores, they are secondary consumers, or second order. But even this is not where the trophic chain always ends, since a secondary consumer can serve as a source of nutrition for a third-order consumer, etc. But in one trophic chain there are no consumers higher than the fifth order due to energy dissipation.

During feeding, “waste” appears at all trophic levels. Green plants lose their leaves partially or completely every year. A significant part of organisms constantly die off for one reason or another. Ultimately, the organic matter created in one way or another must be partially or completely replaced. This replacement occurs thanks to a special link in the trophic chain - decomposers (from the Latin “reduction” - return). These organisms - mainly bacteria, fungi, protozoa, small invertebrates - in the process of vital activity decompose organic remains of all trophic levels of producers and consumers into mineral substances. Minerals, as well as carbon dioxide released during the respiration of decomposers, return to the producers.

Different trophic chains, in turn, are interconnected by common links, forming a very complex system called a trophic network.

The trophic chain in a biogeocenosis is at the same time an energy chain, i.e. a consistent, ordered flow of solar energy transfer from producers to all other links. The flow of energy through an ecosystem can be measured at various points in the ecosystem, thereby establishing how much solar energy is contained in organic matter formed during photosynthesis; how much of the energy contained in the plant material can be used by the herbivore; how much of this energy does the herbivore manage to use before it is eaten by the carnivore, and so on, from one trophic level to another.

People use different types of energy for everything from moving themselves to sending astronauts into space.

There are two types of energy:

• ability to commit (potential)
• actual work (kinetic)

Available in various forms:

• heat (thermal)
• light (radiant)
• movement (kinetic)
• electric
• chemical
• nuclear energy
• gravitational

For example, the food that a person eats contains chemicals and the person's body stores it until he or she uses it as kinetics during work or life.

Classification of types of energy

People use different types of resources: electricity in their homes, produced by burning coal, a nuclear reaction, or a hydroelectric power station on a river. Thus, coal, nuclear and hydro are called source. When people fill their fuel tank with gasoline, the source could be petroleum or even grain growing and processing.

Energy sources are divided into two groups:

• Renewable
• Non-renewable

Renewable and non-renewable sources can be used as primary energy sources such as heat or used to produce secondary energy sources such as electricity.

When people use electricity in their homes, the electricity is likely created by burning coal or natural gas, a nuclear reaction or hydroelectric power plant on a river, or from several sources. People use crude oil (non-renewable) to fuel their cars, but they can also use biofuels (renewable) like ethanol, which is made from processed corn.

Renewable

There are five main renewable energy sources:

• Solar
• Geothermal heat inside the Earth
• Wind energy
• Biomass from plants
• Hydropower from running water

Biomass, which includes wood, biofuels and biomass waste, is the largest source of renewable energy, accounting for about half of all renewables and about 5% of total consumption.

Non-renewable

Most of the resources currently consumed come from non-renewable sources:

• Petroleum products
• Liquefied hydrocarbon gas
• Natural gas
• Coal
• Nuclear energy

Non-renewable energy accounts for about 90% of all resources used.

Does fuel consumption change over time?

Sources of energy consumed change over time, but change occurs slowly. For example, coal was once widely used as a heating fuel for homes and commercial buildings, but the specific use of coal for these purposes has declined over the past half-century.

Although the share of renewable fuels in total primary energy consumption is still relatively small, its use is growing in all sectors. In addition, the use of natural gas in the electricity sector has increased in recent years due to low natural gas prices, while the use of coal in this system has declined.

For the existence and development of human society are necessary. A decisive role in the development of world energy belongs to energy resources, to clarifying the question of what geological and explored reserves of various energy sources and, in particular, oil and gas, humanity has, what is the energy potential of our planet.

According to the degree of durability, energy sources are divided into renewable and non-renewable. Renewable or inexhaustible energy sources include: solar energy, wind energy, tidal energy, hydropower, geothermal energy.

Non-renewable energy sources: nuclear energy and caustobiolite energy. Caustobiolites are combustible minerals (causto - combustible, bios - organic, lithos - stone). These include coal, oil, natural hydrocarbon gases, shale, and peat.

World energy sources: solar energy

Every day the Earth receives 1.5⋅10*22 J solar energy. About 30% of the sun's rays are reflected by clouds and the earth's surface, but most penetrate through the atmosphere. By warming the atmosphere, oceans and land, the sun's heat causes winds, rain, snowfall and ocean currents.

However, all the energy is re-radiated into cold space, keeping the earth's surface in thermal equilibrium.

A small part of solar energy is accumulated in lakes and rivers, while the other part is accumulated in living plants and animals. Solar energy has properties that are not found in any other source: it is renewable, environmentally friendly, controllable, and is thousands of times larger than all the energy that is currently used.

Solar energy is used to heat greenhouses and houses; it is accumulated in solar panels, which convert solar radiation into electricity; solar panels or photocells are used on spaceships to provide astronauts with electricity when working in outer space. The disadvantage of this energy is that the sun's rays are scattered by the earth's surface and a large surface is required to collect sunlight.

Wind energy

Approximately 46% of incoming solar energy is absorbed by the ocean, land and atmosphere. This energy drives winds, waves and ocean currents, warms the seas and produces weather fluctuations. Grade wind energy on a global scale - about 10*15 W, however, most of the energy is concentrated in winds blowing at sky-high altitudes and, therefore, is not available for use on the land surface. Steady surface winds have a power of about 10*12 W and can be used by wind turbines and in sea transportation.

In recent years, global wind energy production has increased by 28% annually. It is expected that by 2020 this energy will account for up to 10% of the world's electricity.

In 2005, a law of the Republic of Azerbaijan was adopted on the use of solar and wind energy, which is sufficient in the country.

Energy of ebbs and flows

Tides are the result of the gravitational attraction of the Moon and the Sun, and the influence of the Moon is much greater. The strength of the tides is an expression of the force of the planet's rotation. The height of the tides is not the same everywhere.

It rarely exceeds one meter at great depths in the ocean, and over the continental shelf it can reach up to 20 meters. The power of tides is estimated at 0.85⋅10*20 J. In France (Rance River) and Russia (Kislaya Guba), stations are already generating electricity from tidal waves. There are many problems in the disposal of ebb and flow tides. For effective operation of the stations, a tidal wave height of more than 5 m and the presence of bays - estuaries - blocked by light dams are required. But almost everywhere, coastal tides have a height of about 2 m, and only about 30 places on Earth meet these requirements. The most important of them are: two adjacent bays - Fundy (Canada) and Passamuquoddy (USA); the French coast along the English Channel, where the Rance station has been successfully operating for many years, the Irish Sea, the estuaries of the rivers of England, the White Sea (Russia) and the Kimberley coast (Australia). Tidal energy could be quite important in the future because it is one of the few energy systems that operates without serious damage to the environment.

Hydropower

Approximately 23% of solar radiation is spent on the evaporation of water, which then falls in the form of rain and snow.

Water energy is a renewable resource. The power of water was harnessed in primitive ways for thousands of years before the twentieth century, when large-scale damming of rivers began to produce electricity. Of all renewable energy resources, water power is the most intensively used. But the unfavorable circumstance is that dams have a finite and, most likely, short lifespan. A moving stream of water carries a load of fine clay particles in suspension; once the flow is blocked and the water speed drops, this material is deposited, and the reservoir can be completely filled with them in 50-200 years.

The greatest untapped potential of this energy can be used where there are large reserves of water energy.

Geothermal energy

When diving 1 km deep into the earth, the temperature increases from 15 to 75 C. In the earth's core, the temperature probably exceeds 5000 C. On average, 6.3⋅10*6 J of energy comes from the interior to the surface. In addition, geothermal energy is associated with the decay of radioactive elements such as U

238, U 235, Th 232, K 40, which are distributed in dispersed form everywhere in the depths. At the same time, underground water is heated and comes to the surface in the form of steam and hot water (geysers). Geothermal hot water is used in Iceland, Japan, Italy, Indonesia, the Philippines, Russia, America and New Zealand to heat houses, swimming pools, and greenhouses. But they are still of little importance compared to the production of electricity.

Atomic energy

Nuclear energy can be obtained through two processes. The first is the fusion or synthesis of light elements such as hydrogen and lithium, which produces heavier elements. These are processes that occur in the Sun and in a hydrogen bomb, but they are difficult to control; perhaps in the future the synthesis of such elements may become the main source of energy. The second process is the fission (decay) of heavy elements such as uranium and thorium. This is the process that takes place in an atomic bomb. Because this reaction can be controlled, the fission of heavy elements is already used to generate electricity in nuclear power plants. Only uranium-235 has a natural ability to decay, which makes up only 0.7% of the total number of natural uranium atoms. The uranium-235 chain reaction was first carried out by Professor Enrico Fermi on December 2, 1942, in one of the most important experiments in Earth's history. The cost of isolating uranium-235 atoms is high. However, the decay of one atom of uranium-235 releases 3.2⋅10*11 J of energy.

Since 1 g of uranium-235 atom contains about 2.56⋅10-21 atoms, the decay of 1 g of uranium produces about 8.19⋅10*10 J, which is equivalent to the energy obtained from the combustion of 2.7 tons of coal. Currently, about 300 nuclear power plants operate on uranium-235. The United States ranks first in the use of nuclear energy (about 50%), followed by Europe (30%) and Japan (12%). When using nuclear energy, there is an acute problem of safety, as well as the problem of disposal of radioactive waste.

Fossil fuels

Currently, three types of fossil fuels are used: coal, oil and natural gas. They account for about 90% of the world's energy. Coal. World reserves of all types of coal are estimated at 13,800 billion tons, and additional potential resources at 6,650 billion tons. The distribution geography is as follows: approximately 43% of the world’s coals are located in Russia, 29% in North America, 14.5% in Asian countries, mainly in China, and 5.5% in Europe. The rest of the world accounts for 8%.

Although coal is not the leading fuel worldwide, it is still dominant in some countries, and it is possible that in the future, difficulties in the supply of oil and gas will lead to increased use of coal. There are many difficulties when using coal. It contains from 0.2% to 7% sulfur, present mainly in the form of pyrite FeS2, ferrous sulfate FeSO4⋅7H2O, gypsum CaSO4⋅2H2O and some organic compounds.

When coal burns, it releases oxidized sulfur, which is released into the atmosphere causing acid rain and smog. Another problem is coal mining itself. Underground mining methods are difficult and even dangerous. Open-pit mining is more efficient and less dangerous, but it causes disruption of the surface layer over a large area. In the modern world, oil and natural hydrocarbon gases are mainly used as energy sources.

For the existence of living organisms, the operation of machines and mechanisms, it is necessary energy. Organisms receive it along with food, and energy comes to machines and mechanisms from various sources. Let's consider what energy sources for machines and mechanisms are used by humans.

The most common source of energy on Earth is fossil fuels- oil, gas, coal, peat. By burning them at thermal power plants, in internal combustion engines of cars, tractors, ships, diesel locomotives, and airplanes, energy is obtained. The disadvantage of this method of energy production is environmental pollution - many harmful substances enter the atmosphere. In addition, oil, gas, and coal reserves are limited. And burning them only to produce energy is not economically profitable, since thousands of chain substances and materials are also made from them, in particular rubber, plastics, washing powders, linoleum, and artificial leather.

Another powerful source of energy is water, which falls from the height of an artificial barrier - a dam - and forces the mechanisms that generate electrical energy at hydroelectric power stations to move. From Figure 120 it becomes clear that hydroelectric power stations are built on deep rivers with appropriate terrain. Such an energy source does not pollute the atmosphere, but causes harm to natural ecosystems. Let's find out which one.

An integral part of a hydroelectric power station is an artificial reservoir - a reservoir, the construction of which requires the flooding of vast areas. As a result, fertile soils are under water. The mechanisms of such stations partially destroy the inhabitants of reservoirs, and the dam blocks the path of fish to spawning grounds.

For example, the Dnieper Hydroelectric Power Station, the first hydroelectric power station in Ukraine, was built 70 years ago on the Dnieper in the Zaporozhye region. Nowadays, the waters of the Dnieper give their energy to people at five more hydroelectric power stations. There are hydroelectric power stations on other rivers in Ukraine, in particular the Dniester and Tereble-Rekskaya in Transcarpathia.

People have long used wind energy— with the help of windmills they ground grain into flour, and set sails on the canoes. And in countries located on the sea coast, where constant winds blow, wind power plants are now being built.

Man tries to use such a powerful source of energy as the Sun. Special devices help him with this - solar panels. However, as you might guess, solar panels do not work at night or on a cloudy day.

Not long ago, a person mastered a special energy - atomic energy, or nuclear (Fig. 121). Scientists have found that the smallest component of molecules - an atom - can be split, that is destroy. This releases energy. At a point marked on paper with a graphite pencil, there are more carbon atoms than can be seen in the sky. Therefore, nuclear fuel is advantageous in that very little of it is needed to produce energy compared to oil, gas, and coal. Material from the site

The most common fuel in nuclear power plants is atoms of the chemical element Uranium. There are reserves of uranium ores on Earth. This energy source does not pollute either air or water if used correctly. However, in the event of an accident at a nuclear power plant, irreparable harm is caused to nature and people, as happened at the Chernobyl nuclear power plant in 1986.

• The vital activity of organisms, the operation of machines and mechanisms require energy expenditure.
• Organisms obtain the energy they need for life through food.
• For machines, energy sources are fuel, water falling from a height, wind and some others.

On this page there is material on the following topics:

• Minerals as energy sources

• Earth energy sources abstracts

• Wind mineral

• website

• Fossil fuels as a source of energy abstract

Questions about this material:

Or in its depths. For example, in many underdeveloped countries, wood is burned for heating and lighting homes, while in developed countries, various fossil fuel sources are burned to generate electricity -,. Fossil fuels are non-renewable energy sources. Their reserves cannot be restored. Scientists are now studying the possibilities of using inexhaustible energy sources.

Fossil fuels

Coal and gas are non-renewable energy sources that were formed from the remains of ancient plants and animals that lived on Earth millions of years ago (more details in the article ““). These fuels are extracted from the earth and burned to produce electricity. However, the use of fossil fuels poses serious problems. At current rates of consumption, known reserves of oil and gas will be exhausted within the next 50 years. Coal reserves will last for 250 years. When these types of fuel are burned, gases are formed, under the influence of which a greenhouse effect occurs and acid rain occurs.

Renewable Energy

As the population grows (see article ““), people require more and more energy, and many countries are switching to the use of renewable energy sources - solar, wind, etc. The idea of ​​using them is widely popular, since they are environmentally friendly sources, the use of which does not harm the environment.

Hydroelectric power stations

Water energy has been used for many centuries. Water turned water wheels, which were used for various purposes. Nowadays, huge dams and reservoirs are built and the water is used to generate electricity. The flow of the river turns the wheels of the turbines, converting the energy of the water into electricity. The turbine is connected to a generator, which produces electricity.

The earth receives a huge amount. Modern technology allows scientists to develop new methods of using solar energy. The world's largest solar power plant was built in the California desert. It fully meets the energy needs of 2,000 homes. Mirrors reflect the sun's rays, directing them into the central water boiler. The water boils in it and turns into steam, which rotates a turbine connected to an electric generator.

Wind energy has been used by humans for thousands of years. The wind inflated the sails and turned the mills. To use wind energy, a wide variety of devices have been created to generate electricity and for other purposes. The wind rotates the blades of a windmill, which drive the shaft of a turbine connected to an electric generator.

Atomic energy is thermal energy released during the decay of the smallest particles of matter. The main fuel for producing atomic energy is - contained in the earth's crust. Many people consider nuclear energy to be the energy of the future, but its practical application poses a number of serious problems. Nuclear power plants do not emit toxic gases, but they can create a lot of problems because the fuel is radioactive. It emits radiation that kills everything. If radiation enters the soil or water, it has catastrophic consequences.

Accidents of nuclear reactors and releases of radioactive substances into the atmosphere pose a great danger. The accident at the nuclear power plant in Chernobyl (Ukraine), which occurred in 1986, resulted in the death of many people and the contamination of a vast area. Radioactive waste has threatened all life for thousands of years. Usually they are buried at the bottom of the sea, but cases of waste burial deep underground are also common.

Other renewable energy sources

In the future, people will be able to use many different natural sources of energy. For example, in volcanic areas, technology is being developed to use geothermal energy (heat from the earth's interior). Another source of energy is biogas produced by rotting waste. It can be used for heating homes and heating water. Tidal power plants have already been created. Dams are often built across river mouths (estuaries). Special turbines, driven by the ebb and flow of the tides, generate electricity.

How to make a Savonia rotor:

The Savonia rotor is a mechanism used by farmers in Asia and Africa to supply water for irrigation. To make your own rotor, you will need some thumbtacks, a large plastic bottle, a cap, two gaskets, a 1m long, 5mm thick rod and two metal rings.

How to do it:

1. To make the blades, cut the top off the bottle and cut it in half lengthwise.

2. Using thumbtacks, attach the bottle halves to the cap. Be careful when handling buttons.

3. Glue the gaskets to the lid and insert the rod into it.

4. Screw the rings to the wooden base and place your rotor in the wind. Insert the rod into the rings and check the rotation of the rotor. Having chosen the optimal position for the half of the bottle, glue them to the cap with strong water-repellent glue.