Incandescent electric light did not immediately snuff out all of its rivals: the gas industry fought back with its own incandescent mantle (which used the heat of the gas to induce a glow in another material) and the arc lighting manufacturers with a glass-enclosed arc bulb.[1] Nonetheless, incandescent lighting grew at an astonishing pace: the U.S. alone had an estimated 250,000 such lights in use by 1885, three million by 1890 and 18 million by the turn of the century.[2]

Edison’s electric light company expanded rapidly across the U.S. and into Europe, and its success encouraged the creation of many competitors. An organizational division gradually emerged between manufacturing companies that built equipment and supply companies that used it to generate and deliver power to customers. A few large competitors came to dominate the former industry: Westinghouse Electric and General Electric (formed from the merger of Edison’s company with Thomson-Houston) in the U.S., and the Allgemeine Elektricitäts-Gesellschaft (AEG) and Siemens in Germany. In a sign of its gradual relative decline, Britain produced only a few smaller firms, such as Charles Parsons’ C. A. Parsons and Company—of whom more later. 

In accordance with Edison’s early imaginings, manufacturers and suppliers expanded beyond lighting to general-purpose electrical power, especially electric motors and electric traction (trains, subways, and street cars). These new fields opened up new markets for users: electric motors, for example, enabled small-scale manufacturers who lacked the capital for a steam engine or water wheel to consider mechanization, while releasing large-scale factories from the design constraints of mechanical power transmission. They also provided electrical supply companies with a daytime user base to balance the nighttime lighting load.

The demands of this growing electric power industry pushed steam engine design to its limits. Dynamos typically rotated hundreds of times a minute, several times the speed of a typical steam engine drive shaft. Engineers overcame this with belt systems, but these gave up energy to friction. Faster engines that could drive a dynamo directly required new high-speed valve control machinery, new cooling and lubrication systems to withstand the additional friction, and higher steam pressures more typical of marine engines than factories. That, in turn, required new boiler designs like the Babcock and Wilcox, which could operate safely at pressures well over 100 psi.[3]

But the requirement that ultimately did in the steam engine was not for speed, but for size. As the electric supply companies evolved into large-scale utilities, providing power and light to whole urban centers and then beyond, they demanded more and more output from their power houses. Even Edison’s Pearl Street station, a tiny installation when looking back from the perspective of the turn of the century, required multiple engines to supply it. By 1903, the Westminster Electric Supply Corporation, which supplied only a part of London’s power, required forty-nine Willans engines in three stations to provide about 9 megawatts of power (an average of about 250 horsepower an engine). But demand continued to grow, and engines grew in response.

Perhaps the largest steam engines ever built were the 12,000 horsepower giants designed by Edwin Reynolds and installed in 1901 for the Manhattan Elevated Railway Company and in 1904 for the Interborough Rapid Transit (IRT) subway company. Each of these engines actually consisted of two compound engines grafted together, each with its own high- and low-pressure cylinder, set at right angles to give eight separate impulses per rotation to the spinning alternator (an alternating current dynamo). The combined unit, engine and alternator, weighed 720 tons. But the elevated railway required eight of these monsters, and the IRT expected to need eleven to meet its power needs. The IRT’s power house, with a Renaissance Revival façade designed by famed architect Stanford White, filled a city block near the Hudson River (where it still stands today).[4]

How much farther the reciprocating steam engine might have been coaxed to grow is hard to say with certainty, because even as the IRT powerhouse was going up in Manhattan, it was being overtaken by a new power technology based on whirling rotors instead of cycling pistons, the steam turbine. This great advancement in steam power borrowed from developments that had been brewing for decades in its most long-standing rival, water power.

Niagara

The signature electrical project of the turn of the twentieth century was the Niagara Falls Power Company. The immense scale of its works, its ambitions to distribute power over dozens of miles, its variety of prospective customers, and its adoption of alternating current: all signaled that the era of local, Pearl Street-style direct-current electric light plants was drawing to a close.

The tremendous power latent in Niagara’s roaring cataract as it dropped from the level of Lake Erie to that of Lake Ontario was obvious to any observer—engineers estimated its potential horsepower in the millions—the problem was how to capture it, and where to direct it. By the late nineteenth century, several mills had moved to draw off some of its power locally. But Niagara could power thousands of factories, with each having to dig its own canals, tunnels and wheel pits to draw off the small fraction of waterfall that it required. New York State law, moreover, forbid development in the immediate vicinity of the falls to protect its scenic beauty. The solution ultimately decided on was to supply power to users from a small number of large-scale power plants, and the largest nearby pool of potential users lay in Buffalo, about twenty miles away.[5]

The Niagara project originated in the 1886 designs of New York State engineer Thomas Evershed for a canal and tunnel lined with hundreds of wheel pits to supply power to an equal number of local factories. But the plan took a different direction in 1889 after securing the backing of a group of New York financiers, headed once again by J.P. Morgan. The Morgan group consulted a wide variety of experts in North America and Europe before settling on an electric power system as the best alternative, despite the unproven nature of long-distance electric power transmission. This proved a good bet: by 1893, Westinghouse had proved in California that it could deliver high-voltage alternating current over dozens of miles, convincing the Niagara company to adopt the same model.[6]

By 1904, the company had completed canals, vertical shafts for the fall of water, two powerhouses with a total capacity of 110,000 horsepower, and a mile-long discharge tunnel. They supplied power to local industrial plants, the city of Buffalo, and a wide swath of New York State and Ontario.[7] The most important feature of the power plant for our story, however, were the Westinghouse generators driven by water turbines, each with a capacity of 5,000 horsepower each. As Terry Reynolds, a historian of the waterwheel, put it, this was “more than ten times [the capacity] of the most powerful vertical wheel ever built.”[8] Water turbines had made possible the exploitation of water power on a previously inconceivable scale; appropriately so, for they originated from a hunger on the European continent for a power that could match British steam.

Water Turbines

The exact point at which a water wheel becomes a turbine is somewhat arbitrary; a turbine is simply a kind of water wheel that has reached a degree of efficiency and power that earlier designs could not approach. But the distinction most often drawn is in terms of relative motion: the water in a traditional wheel pushes the vane along with the same speed and direction as its own flow (like a person pushing a box along the floor). A turbine, on the other hand, creates “motion of the water relative to the buckets or floats of the wheel” in order to extract additional energy: that is to say, it uses the kinetic energy of the water as well as its weight or pressure. That can occur through either impulse (pressing water against the turning vanes), or reaction (shooting water out from them to cause them to turn) but very often includes a combination of both.[9]

The exact origins of the horizontal water wheel are unknown, but they had been used in Europe since at least the late Middle Ages. They offered by far the simplest way to drive a millstone, since it could be attached directly to the wheel without any gearing, and remained in wide use in poorer regions of the continent well into the modern period. For centuries, the manufacturers and engineers of Western Europe focused their attention on the more powerful and efficient vertical water wheel, and this type constitutes most of our written record of water technology. Going back to the Renaissance, however, descriptions and drawings can be found of horizontal wheels with curved vanes intended to capture more of the flow of water, and it was the application of rigorous engineering to this general idea that led to the modern turbine. The turbine was in this sense the revenge of the horizontal water wheel, transforming the most low-tech type of water wheel into the most sophisticated.

All of the early development of the water turbine occurred in France, which could draw on a deep well of hydraulic theory but could not so easily access coal and iron to make steam as could their British neighbors. Bernard Forest de Belidor, an eighteenth-century French engineer, recorded in his 1737 treatise on hydraulic engineering the existence of some especially ingenious horizontal wheels, used to grind flour at Bascale on the Garonne. They had curved blades fitted inside a surrounding barrel and angled like the blades of a windmill, such that “the water that pushes it works it with the force of its weight composed with the circular motion given to it by the barrel…”[10] Nothing much came of this observation for another century, but Belidor had identified what we could call a proto-turbine, where water not only pushed on the vanes but also glided down through them like the breeze on the arms of a windmill, capturing more of its energy.

In the meantime, theorists came to an important insight. Jean-Charles de Borda, another French engineer (there will be a lot of them in this part of the story), was only a small child in a spa town just north of the Pyrenees when Belidor was writing about water wheels. He studied mathematics and wrote mathematical treatises, became an engineer for the Army and then the Navy, undertook several scientific voyages, fought in the American Revolutionary War, and headed the commission that established the standard length of the meter. In the midst of all this he found some time in 1767 to write up a study on hydraulics for the French Academy of Sciences, in which he articulated the principle that, to extract the most power from a water wheel, the water should enter the machine without shock and leave it without velocity. Lazare Carnot, father of Sadi, restated this principle some fifteen years later, in a treatise that reached a wider audience than de Borda’s paper.[11]

Though it is obviously impossible for the water to literally leave the wheel without velocity (for after all without velocity it would never leave), it was through striving for this imaginary ideal that engineers developed the modern, highly efficient water turbine.

First came Jean-Victor Poncelet (from now on, if I mention someone, just assume they are French), another military engineer who had accompanied Napoleon’s Grande Armée into Russia in 1812, where he ended up a prisoner of war for two years. After returning home to Metz he became the professor of mechanics at the local military engineering academy. While there he turned his mind to vertical water wheels, and a long-standing tradeoff in their design: undershot wheels, in which the water passed under the wheel, were cheaper to construct but not very efficient, while overshot wheels, where the water came to the top of the wheel and fell on its vanes or buckets, had the opposite attributes.

Poncelet combined the virtues of both by applying the principle of de Borda and Carnot. The traditional undershot waterwheel had a maximum theoretical efficiency of 50%, because the ideal wheel turned at half the speed of the water current, allowing the water to leave the vanes of the wheel behind with half of its initial velocity. The appearance of cheap sheet iron had made it possible to substitute metal vanes for wooden, and iron vanes could easily be bent in a curve. By curving the vanes of the wheel just so towards the incoming water, Poncelet found that it would run up the cupped vane, expending all of its velocity, and then fall out of the bottom of the wheel.[12] He published his idea in 1825 to immediate acclaim: “no other paper on water-wheels… had proved so interesting and commanded such attention.”[13]

Poncelet’s advance hinted at the possibility of a new water-powered industrial future for France. His wheel design soon became a common sight in a France eager to develop its industrial might, and richer in falling water than in reserves of coal. It inspired the Société d’Encouragement pour l’Industrie Nationale, an organization founded in 1801 to push France to be more industrially competitive with Britain, to offer a prize of 6,000 francs to anyone who “would apply on a large scale, in a satisfactory manner, in factories and manufacturing works, the water turbines or wheels with curved blades of Belidor.” The revenge of the horizontal wheel was at hand.[14]

Benoît Fourneyron, an engineer at a water-powered ironworks in the hilly country near the Swiss border, claimed the prize in 1833. Even before the announcement of the prize, he had, in fact, already undertaken a deep study of hydraulic theory, reading up on Borda and his successors. He had devised and tested an improved “Belidor-style” wheel, applying the curved metal vanes of Poncelet to a horizontal wheel situated in a barrel-shaped pit, which we can fairly call the first modern water turbine. He went on to install over a hundred of these turbines around Europe, but his signal achievement was the 1837 spinning mill amid the hills of the Black Forest in Baden, which took in a head of water falling over 350 feet and generated sixty horsepower at 80% efficiency. The spinning rotor of the turbine responsible for this power was a mere foot across and weighed only forty pounds. A traditional wheel could neither take on such a head of water nor derive so much power, so efficiently, from such a compact machine.[15]

Steam Turbines

The water turbine was thus a far smaller and more efficient machine than its ancestor, the traditional water wheel. Its basic form had existed since at least the time of Belidor, but to achieve an efficient, high-speed design like Fourneyron’s required a body of engineers deeply educated in mathematical physics and a surrounding material culture capable of realizing those mathematical ideas in precisely machined metal. It also required a social context in which there existed demand for more power than traditional sources could ever provide: in this case, a France racing to catch up with rapidly industrializing Britain.

The same relation held between the steam turbine and the reciprocating steam engine: the former could be much more compact and efficient, but put much higher demands on the precision of its design and construction. It was no great leap to imagine that steam could drive a turbine in the same way that water did: through the reaction against or impulse from moving steam. One could even look to some centuries-old antecedents for inspiration: the steam-jet reaction propulsion of Heron’s of Alexandria’s whirling “engine” (mentioned much earlier in this history), or a woodcut in Giovanni Branca’s seventeenth-century Le Machine, which showed the impulse of a steam jet driving a horizontal paddlewheel.  

But it is one thing to make a demonstration or draw a picture, and another to make a useful power source. A steam turbine presented a far harder problem than a water turbine, because steam was so much less dense than liquid water. Simply transplanting steam into a water turbine design would be like blowing on a pinwheel: it would spin, but generate little power.[16]

The difficulty was clear even in the eighteenth century: when confronted in 1784 with reports of a potential rival steam engine driven by the reaction created by a jet of steam, James Watt calculated that, given the low relative density of steam, the jet would have to shoot from the ends of the rotor at 1,300 feet per second, and thus “without god makes it possible for things to move 1000 feet [per second] it can not do much harm.” As historian of steam Henry Dickinson epitomized Watt’s argument, “[t]he analysis of the problem is masterly and the conclusion irrefutable.”[17]

Even when future generations of metal working made the speeds required appear more feasible, one could get nowhere with traditional “cut and try” techniques with ordinary physical tools; the problem demanded careful analysis with the precision tools offered by mathematics and physics.[18] Dozens of inventors took a crack at the problem, nonetheless, including another famed steam engine designer, Richard Trevithick. None found success. Though Fourneyron had built an effective water turbine in the 1830s, the first practical steam turbines did not appear until the 1880s: a time when metallurgy and machine tools had achieved new heights (with mass-produced steels of various grades and qualities available) and a time when even the steam engine was beginning to struggle to sate modern society’s demand for power. It first appeared in two places more or less at once: Sweden and Britain.

Gustaf de Laval burst from his middle-class background in the Swedish provinces into the engineering school at Uppsala with few friends but many grandiose dreams: he was the protagonist in his own heroic tale of Swedish national greatness, the engineering genius who would propel Sweden into the first rank of great nations. He lived simultaneously in grand style and constant penury, borrowing from his visions for an ever more prosperous tomorrow to live beyond his means of today. In the 1870s, while working a day job at a glassworks, he developed two inventions based on centrifugal force generated by a rapidly spinning wheel. The first, a bottle-making machine, flopped, but the second, a cream separator, became the basis for a successful business that let him leave his day job behind.[19]

Then, in 1882 he patented a turbine powered by a jet of steam directed at a spinning wheel. De Laval claimed that his inspiration came from seeing a nozzle used for sandblasting at the glassworks come loose and whip around, unleashing its powerful jet into the air; it is also not hard to see some continuity in his interest in high-speed rotation. De Laval used his whirling turbines to power his whirling cream separators, and then acquired an electric light company, giving himself another internal customer for turbine power.[20]

Though superficially similar to de Branca’s old illustration, de Laval’s machine was far more sophisticated. As Watt had calculated a century earlier, the low density of steam demanded high rotational speeds (otherwise the steam would escape from the machine having given up very little energy to the wheel) and thus a very high-velocity jet: de Laval’s steel rotor spun at tens of thousands of rotations per minute in an enclosed housing. A few years later he invented an hourglass-shaped nozzle to propel the steam jet to supersonic speeds, a shape that is still used in rocket engines for the same purpose today. Despite the more advanced metallurgy of the late-nineteenth century, however, de Laval still ran up against its limits: he could not run his turbine at the most efficient possible speed without burning out his bearings and reduction gear, and so his turbines didn’t fully capture their potential efficiency advantage over a reciprocating engine.[21]

Meanwhile, the British engineer Charles Parsons came up with a rather different approach to extracting energy from the steam, which didn’t require such rapid rotation. Whereas De Laval strove up from the middle class, Parsons came from the highest gentry. Son of the third Earl of Rosse, he grew up in a castle in Ireland, with grounds that included a lake and a sixty-foot-long telescope constructed to his father’s specifications. He studied at home under, Robert Ball, who later became the Astronomer Royal of Ireland, then went on to graduate from Cambridge University in 1877 as eleventh wrangler—the eleventh best in his class on the mathematics exams.[22]

Despite his noble birth, Parsons appeared determined to find his own way in the world. He apprenticed himself at Elswick Works, a manufacturer of heavy construction and mining equipment and military ordnance in Newcastle on Tyne. He spent a couple years with a partner in Leeds trying to develop rocket-powered torpedoes before taking up as a junior partner at another heavy engineering concern, Clarke Chapman in Gateshead (back on the River Tyne).[23]

His new bosses directed Parsons away from torpedoes toward the rapidly growing field of electric lighting. He turned to the turbine concept in search of a high-speed rotor that could match the high rotational speeds of a dynamo. Parsons came up with a different solution for the density problem than Laval’s. Rather than try to extract as much power as possible from the steam jet with one extremely fast rotor, he would send the steam through a series of rotors arranged horizontally. They would then not have to spin so quickly (though Parson’s first prototype still ran at 18,000 rotations per minute), and each could extract a bit of energy from the steam as it flowed through the turbine, dropping in pressure. This design extended the two-or three- stages of pressure reduction in a multi-cylinder steam engine into a continuous flow across a dozen or more rotors. Parsons’ approach created some new challenges (keeping the long, rapidly spinning shaft from bowing too far in one direction or the other, for example) but ultimately most future steam turbines would copy this elongated form.[24]

The Rise of Turbines

Parsons soon founded his own firm to exploit the turbine. Because it has far less inherent friction than the piston of a traditional engine, and because none of its parts have to touch both hot and cold steam, a turbine had the potential to be much more efficient, but they didn’t start out that way. So his early customers were those who cared mainly about the smaller size of turbines: shipbuilders looking to put in electric lighting without adding too much weight or using too much space in the hull. In other applications reciprocating engines still won out.[25]

Further refinements, however, allowed turbines to start to supplant reciprocating engines in electrical systems more generally: more efficient blade designs, the addition of a regulator to ensure that steam entered the turbine only at full pressure, the superheating of steam at one end and the condensing of it at the other to maximize the fall in temperature across the entire engine. Turbo-generators—electrical dynamos driven by turbines—began to find buyers in the 1890s. By 1896, Parsons could boast that a two-hundred-horsepower turbine his firm constructed for a Scottish electric power station ran at 98% of its ideal efficiency, and Westinghouse had begun to develop turbines under license in the United States.[26]

At the same time, Parsons was pushing for the construction of ships with turbine powerplants, starting with the prototype Turbinia, which drove nine propellers with three turbines and achieved a top speed of nearly forty miles-per-hour. Suitably impressed, the British Admiralty ordered turbine-powered destroyers (starting with Viper in 1897), but the real turning point came in 1906 with the completion of the first turbine-driven battleship (Dreadnought) and transatlantic steamers (Lusitania and Muaretania), all supplied with Parsons powerplants.[27]

The very first steam turbines had demonstrated their advantage over traditional engines in size; a further decade-and-a-half of development allowed them to realize their potential advantages in efficiency; and now these massive vessels made clear their third advantage: the ability to scale to enormous power outputs. As we saw, the monster steam engines at the subway power house in New York could generate 12,000 horsepower, but the turbines aboard Lusitiania churned out half again as much, and that was far from the limit of what was possible. In 1915, the Interborough Rapid Transit Company, facing ever-growing demand for power with the addition of a third (express) track to its elevated lines, installed three 40,000 horsepower turbines for electrical generation, obsoleting Reynolds’ monster engines of a decade earlier. By the 1920s, 40,000 horsepower turbines were being built in the U.S., and burning half as much coal per watt of power generated as the most efficient reciprocating engines.[28]

Parsons lived to see the triumph of his creation. He spent his last years cruising the world, and preferred to spend the time between stops talking shop with the crew and engineers rather than lounging with other wealthy passengers. He died in 1931, at age 76, in the Caribbean while aboard ship on the (turbine-powered of course) Duchess of Richmond.[29]

Meanwhile, power usage shifted towards electricity, made widely available by the growth of steam and water turbines and the development of long-distance power transmission, not by traditional steam engines. Niagara was just a foretaste of the large-scale water power projects made feasible by the newly found capacity to transmit that power wherever it was needed: the Hoover Dam and Tennessee Valley Authority in the U.S., the Rhine power dams in Europe, and later projects intended to spur the modernization of poorer countries, from the Aswan Dam on the Nile and the Gezhouba Dam on the Yangtze. In regions with easy access to coal, however, steam turbines provided the majority of all electric power until far in the twentieth century.

Cheap electricity transformed industry after industry. By 1920, manufacturing consumed half of the electricity produced in the U.S., mainly through dedicated electric motors at each tool, eliminating the need for the construction and maintenance of a large, heavy steam engine and for bulky and friction-heavy shafts and belts to transmit power through the factory. The capital barriers to starting a new manufacturing plant thus dropped substantially along with the recurring cost of paying for power, and the way was opened to completely rethink how manufacturing plants were built and operated. Factories became cleaner, safer, and more pleasant to work in, and the ability to organize machines according to the most efficient work process rather than the mechanical constraints of power delivery produced huge dividends in productivity.[30]

By that time, the heyday of the piston-driven steam engine was over. For large-scale installations, it could no longer compete with turbines (whether powered by liquid water or steam). At the same time, feisty new competitors, diesel and gasoline engines, were gnawing away at its share of the lower horsepower market. The warning shot fired by the air engine had finally caught up to steam. It could not outrun thermodynamics, and the incredibly energy-dense new fuel source that had come bubbling up out of the ground: rock oil, or petroleum.