They say that about a hundred years ago, power was never carried far away from its source. Later on, the range of transmission was expanded to a'few miles. And now, in a comparatively short period of time, electrical engineering has achieved so much that it is quite possible, at'will, to convert mechanical energy into electrical energy and transmit the latter over hundreds of kilometres and more in any direction required. Then in a suitable locality the electric energy can be reconverted into mechanical energy whenever it is desirable. It is not difficult to understand that the above process has been made possible owing to generators, transformers and motors as well as to other necessary electrical equipment. In this connection one cannot but mention the growth of electrical power generation in this country. The longest transmission line in pre-Revolutionary Russia was that connecting the Klasson power station with Moscow. It is said to have been but 70 km long, while the present Volgograd-Moscow high-tension transmission line is over 1000 kilometres long. /The reader is asked to note that the English terms "high-tension" and "high-voltage" are interchangeable./
It goes without saying that as soon as the electric energy is produced at the power station, it is to be transmitted over wires to the substation and then to the consumer. However, the longer the wire, the greater is its resistance to current flow. On the other hand, the higher the offered resistance, the greater are the heating losses in electric wires. One can reduce these undesirable losses in two ways, namely, one can reduce either the resistance or the current.
It is easy for us to see how we can reduce resistance: it is necessary to make use of a better conducting material and as thick wires as possible. However, such wires are calculated to require too much material and, hence, they will be too expensive. Can the current be reduced? Yes, it is quite possible to reduce the current in the transmission system by employing transformers. In effect, the waste of useful energy has been greatly decreased due to high-voltage lines. It is well known that high voltage means low current, low current in its turn results in reduced beating losses in electrical wires. It is dangerous, however, to use power at very high voltages for anything but transmission and distribution. For that reason, the voltage is always reduced again before the power is made use of.
LASERS. The Ukrainian scientists are successfully developing quantum generators, called lasers, for emitting light amplitude radio waves. Theoretical calculations have shown that lasers are very likely to transform the energy of light radio waves into electrical energy with efficiency amounting to about 100 per cent. It means that electrical power might be transmitted over considerable distances with negligible losses and what is very important without the use of transmission lines.