Lester Allan Pelton (September 5, 1829 – March 14, 1908) was an American

inventor An invention is a unique or novel device, method, composition, idea or process. An invention may be an improvement upon a machine, product, or process for increasing efficiency or lowering cost. It may also be an entirely new concept. If an ...

who contributed significantly to the development of hydroelectricity and hydropower in the

American Old West The American frontier, also known as the Old West or the Wild West, encompasses the geography, history, folklore, and culture associated with the forward wave of American expansion in mainland North America that began with European colonial ...

as well as world-wide. In the late 1870s, he invented the '' Pelton water wheel'', at that time the most efficient design of the impulse water turbine. Recognized as one of the fathers of hydroelectric power, he was awarded the

Elliott Cresson Medal The Elliott Cresson Medal, also known as the Elliott Cresson Gold Medal, was the highest award given by the Franklin Institute. The award was established by Elliott Cresson, life member of the Franklin Institute, with $1,000 granted in 1848. The ...

during his lifetime and is an inductee of the National Inventors Hall of Fame.

Early life

Lester A. Pelton was born in a log-cabin in rural Vermilion Twp., Erie County, Ohio.Genealogy of the Pelton Family in America; 1892, by J.M. Pelton His grandfather, Captain Josiah Pelton, who lost most of his assets as a sea-captain during the War-of-1812 era, shortly later brought his family to Ohio. Lester's father was Allen Pelton, and his mother was Fanny Cuddeback, from another local early pioneer family. As a youngster, Lester worked on his family's farm and probably attended the nearby "Cuddeback" grade-school. In 1850, young Pelton, along with several other local males, emigrated from Ohio to participate in the

California gold rush The California Gold Rush (1848–1855) was a gold rush that began on January 24, 1848, when gold was found by James W. Marshall at Sutter's Mill in Coloma, California. The news of gold brought approximately 300,000 people to California fro ...

. He was not successful as a gold-miner, but he fished the Sacramento River and sold his catch locally; and he worked in wood-milling and carpentry. In 1860, after the gold strikes in the nearby

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily ...

he relocated to

Camptonville Camptonville (formerly, Comptonville and Gold Ridge) is a small town and census-designated place (CDP) located in northeastern Yuba County, California. The town is located northeast of Marysville, off Highway 49 between Downieville and Nevada ...

—near the Yuba River and the California Mother Lode country—where he made his living as a

millwright A millwright is a craftsperson or skilled tradesperson who installs, dismantles, maintains, repairs, reassembles, and moves machinery in factories, power plants, and construction sites. The term ''millwright'' (also known as ''industrial mecha ...

and

carpenter Carpentry is a skilled trade and a craft in which the primary work performed is the cutting, shaping and installation of building materials during the construction of buildings, Shipbuilding, ships, timber bridges, concrete formwork, etc. ...

. Pelton spent much of his time reading and observing mining activity; his work and studies gained him critical knowledge of mining equipment and processes and related engineering principles.

Inventing the Pelton wheel

Pelton's ideas for improving the turbine water wheel came from his studies of mining equipment and operations in California's gold rush country. Summary descriptions of the local technology observed by Pelton, and of the science by which his turbine water wheel extracts kinetic energy from a coursing mountain stream follow... Steam-heat powered much of local mining activities but required a lot of wood for fuel; nearby forests were routinely decimated. Turbine water wheels also were used to supply power, but these were inefficient in converting the kinetic energy of mountain streams to horsepower. D.P. Stern reports: "According to a 1939 article by W. F. Durand of Stanford University in Mechanical Engineering, Pelton's invention started from an accidental observation some time in the 1870s. Pelton was watching a spinning water turbine when the key holding its wheel onto its shaft slipped, causing it to become misaligned. Instead of the jet hitting the cups in their middle, the slippage made it hit near the edge; rather than the water flow being stopped, it was now deflected into a half-circle, coming out again with reversed direction. Surprisingly, the turbine now moved faster. That was Pelton's great discovery. In other turbines the jet hit the middle of the cup and the splash of the impacting water wasted energy." Experimenting and modelling, Pelton improved upon the efficiency of the Knight wheel (developed earlier by the

Knight Foundry Knight Foundry, also known as Knight's Foundry and Shops, is a cast iron foundry and machine shop in Sutter Creek, California. It was established in 1873 to supply heavy equipment and repair facilities to the gold mines and timber industry of th ...

at nearby

Sutter Creek Sutter Creek (formerly spelled Sutter's Creek and Suttercreek; formerly named Suttersville) is a city in Amador County, California, United States. The population was 2,501 at the 2010 census, up from 2,303 at the 2000 census. It is accessible vi ...

). The Knight wheel received the streamflow jet slightly off-center and at an angle into a ''single'' turbine cup. Alternatively, the Pelton wheel—by deploying a ''split double'' cup (in effect two cups side-by-side), then splitting the impinging water-jet directly onto the common vane of the double cup—captured a stream's kinetic energy more efficiently. There were two prime results of Pelton's design: it consolidated the introduction of a new physical science into the ancient human quest to develop hydropower, i.e., the science of the ''impulse'' turbine as opposed to the ''reaction'' turbine; and it revolutionized the use of turbines adapted for high

head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may ...

(i.e., elevation energy) sites. Before Pelton, almost all water turbines were reaction machines powered by water pressure, or

, while Pelton's wheel was powered by the kinetic energy of a high velocity water-jet which could be conveniently developed from a small mountain stream.

Building the Pelton wheel

In the late 1870s Pelton modeled, tested and manufactured his first turbine wheel, dubbed the ''Pelton Runner''—later referring to the impulse blades only—at the

Miners Foundry The Miners Foundry (previously Nevada Foundry; Nevada Iron Foundry and Machine Shop, George Allan's Foundry and Machine Works, American Victorian Museum, Miners Foundry and Supply Company; currently Miners Foundry Cultural Center) is located at 32 ...

in Nevada City, California. In 1878, at the Mayflower Mine in Nevada City, he installed the first operational Pelton wheel. At that time the

wheel was being sold as the industry standard, but in a head-to-head competition staged in 1883 at the Idaho Mine in nearby

Grass Valley A grass valley (also vega and valle) is a meadow located within a forested and relatively small drainage basin such as a headwater. Grass valleys are common in North America, where they are created and maintained principally by the work of b ...

, Pelton's design proved much more efficient. The Pelton design provided 90 percent efficiency (of converting streamflow kinetic energy to horsepower) while the next best competitor achieved less than 77 percent—at a time when most extant water wheels typically rated less than 40 percent. The Pelton wheel also provided sustained power during (typical) lowflow conditions in a mountain stream. In 1887 a miner attached Pelton's wheel to a dynamo and produced the first hydroelectric power in the

. In 1895, the largest installation of Pelton's wheel during his lifetime was accomplished at the

North Star Mine Powerhouse The North Star Mine and Powerhouse are located on Lafayette Hill a short distance south of Grass Valley in the U.S. state of California. It was the second largest producer of gold during California's Gold Rush. In 1898, the largest Pelton wheel ...

, Grass Valley, California, by the engineer

Arthur De Wint Foote Arthur De Wint Foote (1849–1933) was an American civil engineer and mining engineer who impacted the development of the American West with his innovative engineering works and entrepreneurial ventures. In Northern California in the late 189 ...

, who designed and installed an over-sized wheel of 30 feet diameter; it performed successfully, greatly increasing the hydropower delivered by the Pelton runners to produce compressed air for mining operations. Pelton patented his wheel as well as his novel design of the double cup runner, and in 1888 formed the Pelton Water Wheel Company in San Francisco to supply the growing demand for hydropower and hydroelectricity throughout the West and world-wide. 'Pelton' is a trademark name for the products of that company, but the term is widely used generically for similar impulse turbines.

Death, legacy and awards

Pelton died in California at the age of seventy-eight and is interred at his family cemetery site in Vermilion, Ohio. His ''Pelton Runner'' design is still used to produce hydroelectric power in the United States and around the world, as shown here. Later designs such as the Turgo turbine, first patented in 1919, and the Banki turbine were inspired by the Pelton wheel. In 1895, The Franklin Institute in Philadelphia, Pennsylvania, awarded Lester Pelton the

, since renamed the Benjamin Franklin Medal, for Pelton's accomplishments of invention in technology. In 2006, he was posthumously inducted into the National Inventors Hall of Fame in

Alexandra Alexandra () is the feminine form of the given name Alexander (, ). Etymologically, the name is a compound of the Greek verb (; meaning 'to defend') and (; GEN , ; meaning 'man'). Thus it may be roughly translated as "defender of man" or "prot ...

, Virginia, formerly in Akron, Ohio. There are memorials and monuments celebrating Pelton and the ''Pelton Runner'' mounted in Camptonvlle, California, in the

in Nevada City, California, and at the

Smithsonian Museum The Smithsonian Institution ( ), or simply the Smithsonian, is a group of museums and education and research centers, the largest such complex in the world, created by the U.S. government "for the increase and diffusion of knowledge". Founded ...

in Washington D.C., California Resort at Disneyland in

Anaheim Anaheim ( ) is a city in northern Orange County, California, part of the Los Angeles metropolitan area. As of the 2020 United States Census, the city had a population of 346,824, making it the most populous city in Orange County, the 10th-most p ...

, among other sites. In 1958, the actor William Hudson was cast as Pelton in the episode "Wheel of Fortune" on the syndicated television anthology series, '' Death Valley Days'', hosted by Stanley Andrews. The episode focuses on Pelton's development of the principles of hydraulic mining.

References

External links