According to BP's Global Energy Outlook 2030, the trends in the global energy economy will not change in the next two decades. Along with the growth of the population and its income, the level of electricity consumption will grow steadily.
At the same time, now the main source of energy for mankind, like a hundred years ago, is fossil fuels. Despite the fact that atomic energy has been under the control of people for more than half a century, its share in the world energy system today will hardly reach one tenth. But after people mastered controlled nuclear fission, it was believed that nuclear energy would soon replace fossil fuels. The latter, as you know, is becoming less and less: all forecasts agree that, while maintaining the current rates of oil and gas production, we will have enough for several decades, and coal for a century or two.
In the middle of the last century, soon after the appearance of the first atomic and hydrogen bombs, the ideas of controlled thermonuclear fusion began to spread first in the Soviet Union, and later in other countries. In 1956, Academician Igor Kurchatov made a proposal for international cooperation in this area.
Despite the fact that mankind knows more than a dozen different reactions of fusion of atoms, in practice only two of them are now being considered. The most simple and achievable: "deuterium + tritium". It is this reaction that takes place in thermonuclear bombs. Its use is due to the fact that two solids can be used as a fuel - lithium-6 deuteride (a source of deuterium) and metallic lithium-6, which, under the action of neutrons from the decay of a nuclear fuse, is capable of fission with the formation of tritium and helium-3 and the release of energy …
The result of the fusion reaction "deuterium + tritium" is the formation of helium-4, a neutron and the release of energy. A powerful flux of neutrons and a temperature of a million degrees bring certain difficulties to its control: such a dangerous and hot plasma must somehow be contained. One of the first and most developed solutions is a magnetic trap called a tokamak. The principle of operation is to hold a lump of high-temperature plasma in the air using several powerful magnets. In this case, the magnet is in the form of a ring.
Scientists have achieved the greatest success in the ITER project, which is being carried out in the south of France by the efforts of several states. It is an experimental thermonuclear reactor that can generate electricity and will be the first commercial power plant based on thermonuclear fusion. The construction of the complex began in 2010, and the launch for the first experiments is scheduled for 2020.
Another promising reaction for controlled synthesis is “deuterium + helium-3”. Unlike the previous one, the reaction entails many times less flux of dangerous neutrons, instead of which protons are released, and they are easy to capture and even use to generate energy. In addition, the initial fuel for synthesis is inactive, and its storage is not difficult. At the same time, in the event of an accident, such a reactor will practically not pollute the environment.
However, helium-3 is considered as a fuel only for the long term. This element is a byproduct of the reactions taking place on the sun.On Earth, with its dense atmosphere, its prevalence is very low, so that all the isotope used for scientific and industrial needs is obtained artificially as a decay product of tritium. But on the Moon, where there is no atmosphere, the reserves of helium-3 are estimated at 10 million tons, so in the future the possibility of industrial production of this mineral on the Moon and delivery to the Earth is being considered. This can be very beneficial: when only 1 kg of helium-3 and 670 g of deuterium enter into the reaction, energy is released, which would be formed during the combustion of 15 thousand tons of oil. Unfortunately, today the launch of such a reaction is technically impossible, since this requires a much higher temperature than for the synthesis of "deuterium + tritium".
For all the time that we have known thermonuclear fusion, the world has repeatedly been surrounded by sensations regarding a new breakthrough in this area. All of them concerned cold thermonuclear fusion - a hypothetical possibility to carry out fusion without heating the working fluid to millions of degrees. Until now, all these reports have not been confirmed by experiments. Of course, the fact that cold thermonuclear fusion is still possible is permissible, but there have been no significant progress in this direction yet.
At a distance of about 150 million kilometers from us is the most important source of energy in the life of our planet - our Sun. All the same thermonuclear reactions take place here. It was their energy that gave birth to life on our planet, released oxygen, it underlies the chemical energy of oil and gas, as well as the reserves of helium-3 on the moon.
The energy sent by the Sun to the Earth in the form of light radiation would be enough for humanity with interest for any needs. In the equatorial region, our planet receives about 2.5 kW of energy for every square meter of the surface. So why not use this free, safe and readily available energy instead of burning tons of oil?
Direct methods of converting solar energy into electrical energy are still too primitive. It is worth recognizing that science, which has stepped so far in many directions, does not yet allow the use of solar energy efficiently enough. The most technologically advanced solar panels are based on silicon photodiodes, semiconductors, inside which, under the influence of light, electricity is generated without additional transformations. Such panels are built into calculators, electronic clocks and other small devices. Nevertheless, until recently, batteries were so expensive and inefficient that even after several decades of work they could not recoup their production costs. But times change, new materials appear, and production methods are improved every year. Not so long ago, organic semiconductors began to appear, the production of which usually costs much less than silicon. The latest solar battery efficiency record looks already quite convincing - 37.8%.
There are other ways to capture solar energy and convert it into electricity. One of them is the heating of a working medium, for example, water or salt, which in turn rotates turbines that generate electricity. The Crescent Dunes Solar Energy Project, near Las Vegas, already generates up to 110 MW of electricity on average ten hours a day. The structure is a tower 165 m high. Inside the tower there is a reservoir with a working fluid - molten salt with a temperature of about 1000 ° C, as well as a heat exchanger and the infrastructure necessary for generating electricity. The tower will be provided with the necessary sunlight by 10 thousand mirrors, which will be located around it at a distance of up to three kilometers. The area of each mirror will be several square meters, and all the light will be focused on a heat exchanger with a size of only 30 m.
Even in ancient times, the wind moved ships and forced mills to work.Since then, the needs of mankind have increased by several orders of magnitude, but the wind has blown and continues to blow. Many countries are already successfully using wind to generate electricity: in Denmark it brings in almost a third, in Portugal one-fifth of all electricity.
Wind farms have many benefits. They do not pollute the environment, having only a small impact on the local climate. The area occupied by the turbine usually does not exceed 1% of the entire farm, so that the land can be used for agricultural needs without any problems. In densely populated countries they do this: the land for the mast is rented from farmers who carry out their agricultural activities around.
Of course, wind turbines can be installed where there is wind. If the average annual wind speed is below 5 m / s, then the use of generators with a horizontal axis of rotation is impractical. But not so long ago, rotary generators with a vertical axis of rotation appeared, capable of working well at a wind speed of only 1 m / s. With an increase in the average wind speed, the cost of each kilowatt of electricity generated decreases significantly.
China is the world leader in wind energy. In 2006, a law on renewable energy sources was passed here. It was assumed that by 2020 the total capacity of all wind turbines will reach 30 GW. However, the rapid growth of the industry made it possible to cross this threshold already in 2010, and by the end of last year this figure was already 75 GW, which amounted to 26.8% of global production. The world's largest wind farm is located in India and is called Jaisalmer Wind Park. Founded in 2001, it is constantly growing: as of February this year, its total capacity is just over 1000 MW.
Of course, new ways of generating electricity is a huge leap forward. Nevertheless, we have not yet invented sufficiently compact, powerful and inexpensive batteries, so our vehicles still need fuel. Hydrogen is almost an ideal fuel: it has a very high specific heat of combustion, and only water vapor is produced as a result of combustion.
The production of hydrogen is also extremely simple - using electrolysis, water is decomposed into hydrogen and oxygen. Another undoubted plus: hydrogen makes it possible to obtain electricity quite easily and compactly by a catalytic method.
In the future, when mankind learns to get cheap electricity from the Sun, it will be hydrogen that will become the main fuel used to fuel vehicles. At the same time, there is every reason to believe that today's oil exporters like Saudi Arabia, the United Arab Emirates and other Arab countries can become the largest producers of hydrogen. They have everything for this: huge unoccupied territories, very hot sun, constantly clear weather and sufficient funds for the implementation of a daring project. The absence of fresh water is not critical; hydrogen can be obtained from sea water as well.
It is worth mentioning another potential source of colossal energy - antimatter. We know very little about her. It is the complete opposite of matter, of which you and I and everything else in the Universe are made. When matter and antimatter meet, annihilation occurs, as a result of which both one and the other disappear, and energy is released into the surrounding space. According to calculations, the annihilation of 1 kg of matter and the same amount of antimatter releases energy equivalent to an explosion of almost 43 megatons of TNT.
So far, humans have not learned to either get enough or use antimatter. But this does not mean that in the future we will never be able to "put into action" this mysterious and interesting substance.
The famous journalist, political consultant and intellectual Anatoly Wasserman thinks about alternative energy sources in our interview with him.