The struggle for power and glory

Two names representing two different technologies stand out like beacons among the thousands of names and inventions that were such a feature of the 19th century. These two, like boxers in a ring waiting for the contest to start, sparred and weaved in bids to make their beliefs the one the world would accept. But the two were not the inventors of the technology they so passionately believed in and strangely they are better remembered today as the inventors of the gramophone and the vacuum braking system used on trains throughout the world.

The men were Thomas Edison in the DC corner and George Westinghouse in the AC corner. Right from the development of the first DC generator, the problem of distributing the power by cable was apparent. There were huge voltage drops over just a short cable length and the voltage that was produced by the generator was the voltage the consumer had to use because there was no way of changing it and these two factors alone prevented DC from becoming more widely distributed and used.

Traditionally, the contest has been said to be between these two men. In fact, there were many other names including engineers and financiers, now largely forgotten, involved in the war, because a war it was and there were some questionable acts. One name that hasn’t been forgotten is Nikola Tesla, who was well and truly in the AC corner.

Edison is credited with inventing the gramophone, a cine camera and a long-lasting light bulb. But he was also one of the first to use mass production methods, he created the first industrial research laboratory at Menlo Park, is said to be the fourth most prolific inventor in history and many of his inventions established new industries in the 19th century. In his lifetime he founded 14 companies including General Electric, which is still one of the biggest public companies worldwide.

The Edison Electric Light Co was formed in 1878 and he demonstrated his incandescent light bulb the following year at the laboratory. He is reported as saying at the time: “We will make electricity so cheap that only the rich will burn candles.”

In 1890, the Oregon Railroad and Navigation Co’s new steamship, Columbia, was fitted with Edison’s lighting system where it lasted for 15 years. In Europe, there was also wide interest in power generation. In 1835, Hippolyte Pixii built an alternator using a rotating magnet, but he didn’t know how to put his discovery to practical use. Twenty years later, Guillaume Duchenne used AC to contract muscles, but again this was not seen as particularly useful.

By 1878, the Ganz company began working with single-phase AC in Budapest. In 1882, Sebastian de Ferranti, working at the Siemens plant in London, took a keen interest in AC. With Lord Kelvin and others he went on to make an early transformer. By 1891, Ferranti, already a leader in electric lighting, had installed underground cables at 10,000 V in London, confident that the transformer would look after any voltage demanded by the consumer.

Later Ferranti was hired by the London Electric Supply Corporation to design a power station at Deptford on the south bank of the Thames in London. He designed the whole complex including the distribution system and when it was completed in 1891 it was the first power station to supply high-voltage AC.

But the main battle between DC and AC was being fought in America where Westinghouse and Edison, with help from Tesla, were involved in a passionate struggle to have their respective technologies adopted by governments and the public.

DC, the first player on the stage, was relatively easy to make. Its drawback came with the difficulty of sending it over any great distance due to huge voltage and therefore current losses.  Consumers had to be within about 2.5 km of the generator. The other major drawback was the difficulty of changing the voltage. Consumers had to put up with the generated voltage because there was no way to effectively and economically change it.

When Tesla joined Westinghouse, he was convinced that the cyclic nature of AC was the way forward using the polyphase principle. As a result, he developed a series of generators, motors and transformers.

In today’s world, the frequency of AC varies between 50 and 60 Hz. Japan is unusual in having a mixture of frequencies. But in those days even the frequencies were not without challenges. A low frequency makes the design of motors easier and means lower impedance losses which are proportional to frequency. But the low frequency causes noticeable flickering in arc lamps and incandescent light bulbs.

With advancing technologies in transformers, DC was doomed. AC could be provided at any voltage to suit consumers, but more importantly, it could be sent for hundreds or thousands of kilometres down quite small cables with very little loss.

Westinghouse imported several transformers from Europe and began experimenting with an AC network in Pittsburgh.

By 1886, he and his assistants had built a hydroelectric generator that supplied AC to Great Barrington, Mass. Using the transformers, the transmission line voltage was stepped up to 3000 and then reduced to 100 V for electric lighting. The network was so successful that 30 more were built inside a year, along with an induction meter using a rotating magnetic field to measure the current consumed.

By 1887, Edison had 121 power stations, but when their limitations were discussed, he campaigned that AC was far more dangerous to use so he arranged for some of Edison's employees to publicly execute unwanted animals using AC. The science behind this says that 60 Hz AC under adverse conditions is more likely to induce ‘cardiac fibrillation’ in humans compared with the same DC voltage. But the public smear campaign went on and in 1903 Edison workers electrocuted an elephant that had previously killed several people.

Edison went further and proposed electrical executions of criminals and this idea was adopted so that in 1890 William Kemmler became the first man to be put to death in the electric chair. It was a bungled execution because the victim survived 17 seconds of the current flowing until it was increased to a fatal level by the prison authorities.

Afterwards, Westinghouse is reported to have said: “It was a brutal affair. They could have done better with an axe.”

Edison, in a further bid to disgrace and humiliate Westinghouse, then tried to make popular the term “Westinghoused” for those sentenced to death by electricity, but the word did not appeal to the public.

Slowly, AC gained the upper hand. The World’s Columbian Exposition in Chicago in 1891 saw Westinghouse win the contract to build an AC network to power the event. He also established the first long-range power network and distributed AC from the Niagara Falls generators to Buffalo in New York, a distance of some 40 km.

Generating AC was limited to either hydro or reciprocating steam engines. Westinghouse felt that reciprocating steam engines were clumsy and inefficient. Meanwhile, in England, Charles Parsons was experimenting with steam turbines so Westinghouse bought the rights to the turbine and by 1898 he produced a 300 kW unit followed the next year by a 1.5 MW unit for the Hartford Electric Light Co. Westinghouse then went on to develop steam turbines for marine propulsion.

But, as was so common with 19th-century inventors, litigation was just round the corner. Lewis Latimer brought to Edison an improved technique for making carbon to light bulbs. In the meantime, Westinghouse bought Philip Diehl’s competing induction lamp patent rights for US$25,000, which forced the holders of the Edison patent to charge less for these patent rights, effectively lowering the cost of the lamp.

In 1883, the US Patent Office ruled that Edison’s patent was developed from William Sawyer’s invention and was invalid. For six years litigation dragged on until Edison finally won the day. However, in England, Joseph Swan had been granted a patent a year before Edison so he and Swan formed a joint company called Ediswan to make and market bulbs in Britain.

But DC still persisted despite its limitations. The Pearl Street generating station in New York was switched on in 1892 and produced 110 VDC to 59 users in lower Manhattan. In London, the first station driven by steam provided power to several private houses close to the plant while a theatre in Brno became the first public building to be lit using Edison’s light bulbs.

Today, DC is still used by some sections of industry, and railway systems around the world use DC as they can position substations at convenient points along the track. One of the largest rail networks using DC is the British third rail system which, since the early part of the 20th century, has been providing a train service to southern England.

Looking to the future, maybe DC will resurrect itself when electric cars come into their own. Even accepting the current range of around 80 km a charge, there will be a demand for recharging stations with energy that could be provided by solar or wind power on a scale suitable for local distribution, perhaps among the few garages in the high street or special charging bays.

Innovative switching and control systems could ensure a continuous power supply. But all this could depend on the great motoring public having the imagination and the willing wallet to inspire this happening.