Mankind needs more and more energy especially solar energy, which will be difficult or impossible to obtain from non-renewable sources in the near future. Indeed, according to various estimates, explored fossil fuels will suffice for 30-50 years. If we take into account the so-called geological reserves, which will be explored in a timely manner, and their operation is not delayed, then, given the growing level of energy consumption, fossil fuels may be enough for another 100-150 years. And only coal can keep its place in the energy balance for a long time.
However, its use is accompanied by a high level of pollution of the Earth’s atmosphere. Nuclear energy, which today has much more raw materials than fossil fuels, has developed dynamically around the world over the past 20-30 years.
But today, according to many experts, it can no longer be considered a promising type of energy due to the high risk of radioactive contamination, which manifested itself in a series of man-made accidents and disasters, especially during the infamous Chernobyl disaster.
Therefore, the world is increasingly paying attention to the use of so-called renewable energy sources – Earth’s heat, wind energy, tides, biogas, solar radiation, and so on. Almost all of these energy sources are entirely due to the direct action of the Sun. Among these sources, one of the most promising is the direct conversion of solar radiation into electricity in semiconductor solar cells.
Solar radiation energy – is the main source of energy for atmospheric processes; it is measured by the amount of heat and is expressed in megajoules per 1 m². The radiant energy of the Sun reaches the earth’s surface, penetrating the layers of the atmosphere, which partially absorbs, reflects and scatters solar radiation.
Because its reserves are virtually inexhaustible (astronomers have estimated that the Sun will “burn” for several million years), it is attributed to renewable energy.
The heat flux of solar radiation that reaches the Earth is very large. It is more than 5,000 times the total use of all types of fuel and energy resources in the world.
Methods of obtaining electricity and heat from solar energy radiation:
• Getting electricity with photocells.
• Heliothermal energy – heating the surface that absorbs sunlight and the subsequent distribution and use of heat (focusing solar radiation on the vessel with water for further use of heated water in heating or steam generators).
• The “solar sail” can convert sunlight into kinetic energy in airless space.
• Thermal-air power plants (conversion of solar energy into energy of air flow sent to the turbogenerator).
• Solar balloon power plants (generation of water vapor inside the balloon balloon due to heating by solar radiation of the balloon surface covered with a selectively absorbing coating). The advantage – the supply of steam in the cylinder is enough for the power plant to work in the dark and cloudy weather.
The disadvantage of solar energy conversion plants is that they require large areas, and relatively close (within 80 km) from the consumer. Otherwise, the losses in the transmission of electricity will be unacceptably high. However, superconducting power lines may appear later, which will solve the problem, but in the near future, the construction of plants will be limited by the lack of fairly large vacant areas near cities. On the other hand, solar panels can be placed directly on the roofs of houses.
Solar energy is widely used in cases where the inaccessibility of other energy sources in combination with sufficient solar radiation justifies it economically.
Other applications of solar energy include use in telecommunications and communication systems (repeaters, telemetry); to provide electricity to navigation lights, beacons, road signs, lighting of highways at night; for corrosion protection of metal structures and pipelines; in remote non-electrified homes for power supply of household appliances; in burglar alarm systems; in agriculture and arid areas for water extraction and supply; creation of a network of automatic posts equipped with various sensors for environmental monitoring, etc. Finally, in spacecraft and artificial satellites, solar panels play an extremely important role in the on-board power supply systems.
Today, the industry involved in the production of solar panels is experiencing a significant boom. Unlike other microelectronic devices, the production of solar cells in the world is not only not declining, but is characterized by an annual 15% increase over the past 6 years. Hundreds of millions of dollars are spent annually on research in the field of solar energy.
Among the main advantages of solar energy – its eternity and exceptional environmental friendliness. Solar energy reaches the entire surface of the Earth, only the polar regions of the planet suffer from its lack. That is, almost all over the globe, only clouds and night prevent you from using it constantly. This general availability makes this type of energy impossible to monopolize, unlike oil and gas.
The main thing is to use solar energy so that its cost is minimal or even zero. As technology improves and traditional energy resources become more expensive, this energy will find more and more applications.
According to climatic conditions, Australia belongs to the regions with medium intensity of solar radiation. The amount of solar energy per unit area of the earth’s surface during the year is about 1000-1350 kWh / m2.
Currently, the most promising for Australia are the two main areas of use of solar energy for conversion into heat and electricity.
Using solar energy for hot water and heating is the most efficient and well-established method. The main element of active solar heating systems is a flat solar collector.
In Australia, solar heat supply has sufficient experience in use, and the technological potential of domestic industry makes it possible to solve the problem of mass production of solar equipment. Daily productivity of collectors, depending on the scheme and working conditions, makes from 80 to 120 l of hot water at a temperature of 50-55 ° C from 1 m² of a working surface of the solar receiver.
Thus, the use of alternative energy sources in Australia, primarily solar energy, will undoubtedly bring only benefits. The potential of energy based on the use of direct solar radiation is extremely large. Using only 0.0125% of the Sun’s energy could meet all of today’s global energy needs, and using 0.5% to fully cover future needs.