06 / 05 / 2013

Direct and alternating current

The confrontation between direct and alternating current, which began at the very beginning of the XX century, in the time of Nikola Tesla and Thomas Edison, is now acquiring a new relevant basis. As it is known then, despite all the efforts of the great inventor and innovator Thomas Edison, alternating current won the victory. And for good reason, its transmission over long distances, as well as the relative simplicity of the design of AC electric machines, have left direct current far behind. It would seem that he is destined to stay in the tail all his life, only complementing his more advanced brother. However, the realities of the modern high-tech world of electronics allowed us to radically revise the results of this confrontation.

Modern electronic gadgets, which have become widespread in the world recently, work precisely on direct current. Their total energy consumption is already catching up with the consumption of devices running on alternating current. Experts from the University of Pittsburgh have estimated that the share of portable digital devices in the total number of electricity consumers is one fifth, and it is growing very intensively every year. They are sure that in 20-25 years their share will be about 50 %. This is mainly due to significant achievements in the development of alternative energy, including the development of new portable solar panels, as well as significant advances in the use of more energy-efficient LEDs. Already, some modern televisions that use LCD and plasma display panels are equipped with sockets for connecting to the DC network.

With a significant increase in the number of electronic devices operating on direct current, there is no need to convert AC voltage to DC, and vice versa. It is during such transformations that a significant part of the electricity that goes to heating the transformer windings is wasted. The trend of switching to the use of direct current will allow us to abandon energy converters, significantly simplifying the electronic circuits of devices. According to experts, this will lead to even greater energy savings.

The widespread use of electric vehicles, which will eventually be able to use not only on-board batteries, but also their own solar panels, will lead to a significant increase in DC consumers. Many information data processing centers (data centers) that provide the operation of Internet servers are also considering the possibility of completely or partially abandoning the use of alternating current. Now their share of electricity consumption is about 1.3 % of the total number of consumers, and it is constantly growing. For example, the Japanese telecommunications giant NTT already has one data processing center that consumes non-time-changeable electrical energy (direct current). And the American computer giant Intel has conducted a preliminary assessment of the transfer of its data centers to direct current. The resulting estimated savings amounted to $ 1.2 million.

Many American companies have recently been actively implementing the transition to lighting their offices and industrial buildings with constant, rather than alternating voltage. This is primarily due to the introduction of LED lamps.

One way or another, but direct current is becoming increasingly popular among consumers of electric energy. Pretty soon, its share may become higher than the share of alternating current. However, experts in the field of energy are confident that the transmission of large capacities over long distances will still remain the prerogative of alternating current.

 

Source: website "Popular electronics"