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The Evolution of Electrical Generators and Their Importance

The existence of electrical energy has been recognised for millennia. By the latter half of the 17th century, man’s attempts to produce it by mechanical means finally succeeded. The earliest generating devices relied upon the action of friction between two surfaces to produce a visible discharge of static electricity. Progressively more efficient designs produced even bigger voltages, but these machines offered little in the way of practical, day-to-day applications even though, in the early 20th century, one of these electrostatic generators successfully produced 1 000 000 V.

The battery offered a more practical option by allowing electrical energy produced through various chemical reactions to be stored and tapped at will in order to power simple devices, such as the newly invented telegraph machine. Initially, their lifespan was limited and batteries were of no further use once exhausted. Only with the invention of the rechargeable lead-acid battery in 1859 did their use expand to include tasks such as powering electric lighting in train carriages.

In parallel, engineers were working on a means of converting mechanical power into electricity for continuous use, rather than relying on finite or rechargeable stored sources. Following Michael Faraday’s discovery in 1832 that an electrical conductor placed in a varying magnetic field caused an electric current to be induced in the conductor, it was not long before the first practical generators were developed. These were of two distinct types – the dynamo and the alternator. The latter produced the alternating form of current used universally for domestic and industrial supplies, whilst the dynamo, a modification of the alternator, produced a direct current, a difference that later led to the eruption of the historic conflict known as the “War of Currents”, between Thomas Edison and Nikola Tesla, over which of these systems should be adopted in the US.

After an initial defeat, Tesla’s AC system was found to be both more efficient and more cost-effective and was eventually adopted worldwide. Since those early days, distribution networks have drawn their power from a variety of different generating sources. These include hydroelectric dams, nuclear power stations, solar arrays, and wind farms, although most cities are still served predominately by power produced by the use of coal or oil-fired AC generators.

Of course, it is not always required to supply a major city or even and entire region with power. In practice, these machines have many applications in industry and commerce, as well as for domestic use, albeit on a much smaller scale. For such purposes, the mechanical energy is provided mainly by diesel- or petrol-fired engines, although new engine technology has also made possible the use of propane and natural gas.

On industrial and commercial premises, diesel-powered gensets can serve as a backup to mains power in the event of outages, although mines and many heavy industries require them to augment the network supply where this is insufficient to meet peak loads, or to replace it in remote regions without mains power. In the home, the demand for small petrol-driven units has escalated to combat Eskom’s rolling blackouts.

Individual power needs are often unique, requiring unique installations. In South Africa, PacB Power Solutions combines the supply of top-branded generators with the knowledge and expertise to design, install, and maintain a world-class, tailored system.