STEAM LOCOMOTIVES WERE ALMOST UNIVERSAL on the railroads by the end of the 1830s, once horses had been taken off the tracks. It was not until the end of the 19th century that electric power began to challenge steam’s supremacy on the rails. Although electricity has numerous advantages over steam—it is cleaner, more efficient, and ultimately cheaper—it requires greater capital investment, as power has to be provided either by an external delivery system, most commonly an overhead wire or third rail, or by an internal system such as an onboard power generator—technologies that demand a high initial outlay. However, once its benefits had been seen, it superseded steam.
Britain was again a pioneer with electric trains, as it had been with the steam engine (see The Father of Railroads), although it lost out in the technological race once electricity was more widely adopted. As early as 1837, a chemist from Aberdeen, Robert Davidson, made the first electric locomotive. It was battery-powered, as was a second version named Galvani (after its galvanic cells, or batteries) that was exhibited at the Royal Scottish Society of Arts Exhibition in 1841. This massive, 7-ton (7.7-tonne) vehicle managed to haul a load of 6 tons (6.7 tonnes) at 4mph (6.5kph) for a distance of 1½ miles (2.5km), and was tested on the Edinburgh and Glasgow Railway the following year. However, the perennial problem of batteries running out of power—which still limits their use in transportation today—meant Galvani was not much practical use. Railroad workers also opposed it, fearing electric trains would ruin their livelihoods, and destroyed the engine in a fit of Luddite pique.
German industrialist Werner von Siemens developed the first electric passenger train in 1879, and exhibited it on a 985-ft (300-m) circular track in Berlin, Germany. The train operated for several months, using a third-rail system to reach a speed of 8mph (13kph). Britain’s first electric passenger railroad, the narrow-gauge Volk’s electric railroad (named after its inventor, Magnus Volk), was completed in 1883 and, remarkably, still survives today, running 1¼ miles (2km) along Brighton’s seafront. A low-voltage electric generator originally supplied a 50-V current to the small engine via the two running rails. Later the voltage was increased and the gauge widened from a narrow 2ft (60cm) to 2ft 8½in (80cm).
Some fascinating early experiments with electricity took place elsewhere. In Ireland, William Traill used hydro-electricity from a local waterfall to power a railroad for visitors to the Giant’s Causeway tourist attraction. Traill built the 9¼-mile (15-km) Giant’s Causeway, Portrush, and Bush Valley Railway on a 3-ft (90-cm) gauge, and installed turbines and dynamos to provide the power. However, electricity generation was unreliable when the railroad opened in 1887, and steam engines were used to supplement the electric power. Reliability improved once the supply was converted to overhead wires rather than the third rail, which was also hazardous to people crossing the line—in 1895, a cyclist died from electric shock after touching the live rail. Despite its mixed success, Traill’s railroad was ahead of its day in ecological terms, and many lines since, especially in the mountains, have been powered by more sophisticated forms of hydro-energy.
The exception to the near universal adoption of steam for railroads at their inception had been the trolleys—omnibuses that used tracks through towns, so that they would not get stuck on muddy roads. Steam engines trundling through towns would have been not only dangerous but also impractical, as they operated poorly at slow speeds when they had to stop and start a lot, so horses remained the sole form of traction. Consequently, horse-drawn trams were the norm until the electric tramways began to emerge—skipping a technological step. The first commercial electric tram line opened in Lichterfelde, a suburb of Berlin, in 1881. It was built by Werner von Siemens, who had exhibited the first electric train two years earlier. In 1883, the Mödling and Hinterbrühl Tram—the first regular service in the world powered from an overhead line—opened near Vienna, in Austria.
In the US, electric trolleys (the American name for tramways) were pioneered in 1888, on the Richmond Union Passenger Railway in Virginia. The new technology encouraged rapid expansion and in just over 10 years, trolleycars had become almost universal across the country: there had been just 3,000 miles (4,800km) of horse tramways prior to electrification; by 1905, there were more than 20,000 miles (32,000km) of electric trolley lines and the trolleycar became the most common form of urban travel. Although there was a potential hazard associated with trolleys powered from overhead lines, which occasionally resulted in electric shocks, in practice this seems to have been rare.
Elsewhere, the increasing use of tunnels, especially in urban areas and through mountainous regions, stimulated the need for electric locomotives. Despite the success of London’s Metropolitan Railway (see Going Underground), which opened in 1863, it soon became apparent that steam engines in tunnels caused dangerous levels of smoke, leading local authorities to prohibit their use within city limits. Once again Britain, which had developed the first underground railroad, blazed the trail, with a line using electricity. The 3¼-mile (5.1-km) City and South London Railway, the world’s first deep subterranean line, which opened in 1890, was bored through the London clay, so the whole railroad was below ground. Steam could not be used in the poorly ventilated tunnels. At first, cables were suggested as an alternative form of traction, but in the end electricity was used. Small engines provided the power, and at times they could not cope with the heavily loaded trains on the line, which had proved to be an instant success. As a result, it was not unknown for trains to fail to make it up the incline at King William Street, the terminus for the line in the City, and to have to roll back for a second attempt. Nevertheless, electricity rapidly became the power supply of choice for underground railroads and soon the power units were fitted under the passenger cars, eliminating the need for a separate locomotive. The early lines of the London Underground, which had been steam-powered (see Going Underground), were all converted to electricity in the first decade of the 20th century.
The mountains and tunnels of Switzerland made it an obvious site for electric-powered trains. In 1896, the first commercial electric trains ran on the Lugano Tramway and, by 1899, a 25-mile (40-km) stretch of main line between Burgdorf and Thun had been electrified. It was on its mountain routes, however, that Switzerland pioneered electrification. The Simplon Tunnel line was powered by electricity when it opened in 1906 and the St. Gotthard line demonstrated the advantage of electric traction when it was introduced in 1920. Whereas two steam engines struggled to climb up the steep grades pulling a 200-ton (224-tonne) load at 20mph (32kph), one electric locomotive could haul a load of 300 tons (336 tonnes) up at 30mph (48kph). After that, electrification became the norm in Switzerland and began to spread rapidly across Europe. The Swiss success with electricity, combined with a coal shortage after World War I and an abundance of cheap hydro-electricity, drove its progress. Italy, which had already electrified a couple of its mountain lines, and France both drew up ambitious plans to electrify many of their main lines. Technical problems combined with the resistance of railroad managers who still favored steam held up France’s program. Italy, however, rapidly expanded its electrified services, driven by Mussolini, the nation’s dictator after 1925, who saw electric trains as epitomizing modernity.
The United States had just beaten Switzerland to become the first country to electrify a main line when, in 1895, it opened a 4-mile (6.5-km) stretch of the Baltimore Belt Line of the Baltimore and Ohio Railroad—a connection from the main line to New York through a series of tunnels around the edges of Baltimore’s downtown. A 1903 decision by the New York State legislature to outlaw the use of smoke-generating locomotives on Manhattan and in rail tunnels under the Hudson River boosted electrification in the US. As a result, electric locomotives began operation on the New York Central Railroad in 1906. In the 1930s, the Pennsylvania Railroad, which had introduced electric locomotives because of the regulation, electrified all its lines east of Harrisburg, Pennsylvania.
Despite the obvious advantages of electrification, the conversion of railroads to electric power remained patchy. This was partly because railroad managers were resistant to change, but also because it was hard for them to know which of the plethora of incompatible systems to choose. Many different kinds of electric technology were used: as well as various delivery systems, there was a wide variety of voltages, different phases (one-, two-, or three-phase), and types of current—DC (Direct) and AC (Alternating). Even today, there are numerous systems in operation, which hampers the integration of services, especially across national borders.
The most difficult choice that promoters of electrification had to make was whether to use a third-rail or an overhead system. For the most part, overhead was used for mainline railroads, while commuter lines and suburban systems were generally equipped with a third rail. Sir Herbert Walker, the general manager of Britain’s Southern Railway from 1923 to 1937, was a great pioneer of electrification in the country. He decided on the use of a third-rail rather than an overhead system—indeed, on the Brighton line, he replaced the existing overhead with a third-rail system. Nowadays, this is seen as outmoded and inefficient, as it relies on low voltages. However, with a network of more than 1,000 miles (1,600km) of suburban and regional railroad equipped with a third rail, it would now be prohibitively expensive to convert to overhead operation. The London Underground is unusual in that it operates on a four-rail system—one of the only ones in the world (the fourth rail helps to increase the total voltage available).
It was not until after World War II that new railroads were almost invariably powered by electricity and the majority of existing main lines in Europe were electrified. Oddly, however, despite its early adoption of electric-powered trains, very little of the US rail network is electrified today—a few passenger lines in the northeast, and some commuter services—while most mainline trains are powered by diesel engines. In India, too, many trains are still diesel-powered, but in most modernizing Asian countries, electrification of busy lines is now standard, and all high-speed trains around the world are electrically powered.