Lester Allan Pelton
Encyclopedia
Lester Allan Pelton was an American inventor who contibuted significantly to the development of hydropower and hydroelectric power in the old West
and world-wide. In the late 1870's he invented the Pelton water wheel
, then 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
during his lifetime and recently was inducted into the National Inventors Hall of Fame
.
on September 5, 1829. His grandfather, Captain Josiah S. Pelton, who retired after a successful career at sea, had established his family and descendants prominently in the area. Lester's father was Allen Pelton, Josiah's youngest son; his mother was Fanny Cuddeback, she of another locally prominent family. As a youngster Lester worked on the Pelton family farm and attended the Cuddeback School.
In 1850, young Pelton joined a local party of males and emigrated from Ohio to participate in the California gold rush
. But he was not successful as a miner, and for a time he fished the Sacramento River
and sold his catch locally; and he worked in woodmilling and carpentry. In 1860, after the gold strikes in the nearby Sierra Nevada he relocated to Camptonville
—near the Yuba River
and the California Mother Lode
country—where he made his living as a millwright
and carpenter
. 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.
Steam-heat powered much of local mining activities but required a lot of wood for fuel; nearby forests were routinely decimated. Turbine water wheel
s also were used to supply power, but these were inefficient in converting the kinetic energy of mountain streams to horsepower. Further, 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
at nearby Sutter Creek
). 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 consolidatd 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 (i.e., high energy) sites. Before Pelton, almost all water turbines were reaction machines powered by water pressure, 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.
(The Pelton design can be approximated by cupping both hands upward then bringing them together, aligning the fingernails 'back-to-back' to represent the splitter vane between the cupped hands. The split double cup, also called the split bucket, may be seen here
; or here—showing the original Pelton model at the original site of manufacture, Miners Foundry - Allans (sic) Machine Shop, Nevada City, California.)
in Nevada City, California
.In 1878, at the Mayflower Mine in Nevada City, he installed the first operational Pelton wheel. At that time the Knight Foundry
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
, 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 normal 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 Sierra Nevada.
Pelton patent
ed his wheel as well as his novel design of the double cup, 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.
. His Pelton Runner design is still used today to produce hydroelectric power in the United States and around the world. 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, Philadelphia, US, awarded Lester Pelton the Elliott Cresson Medal
—now renamed the Benjamin Franklin Medal
—for his accomplishments of invention in technology. Pelton was inducted into the National Inventors Hall of Fame
in 2006. There are memorials and monuments celebrating Pelton and the Pelton Runner mounted in Camptonville, California
, in the Miners Foundry
in Nevada City, California
, and at the Smithsonian Museum in Washington D.C., among other sites.
American Old West
The American Old West, or the Wild West, comprises the history, geography, people, lore, and cultural expression of life in the Western United States, most often referring to the latter half of the 19th century, between the American Civil War and the end of the century...
and world-wide. In the late 1870's he invented the Pelton water wheel
Pelton wheel
The Pelton wheel is an impulse turbine which is among the most efficient types of water turbines. It was invented by Lester Allan Pelton in the 1870s. The Pelton wheel extracts energy from the impulse of moving water, as opposed to its weight like traditional overshot water wheel...
, then the most efficient design of the impulse water turbine
Water turbine
A water turbine is a rotary engine that takes energy from moving water.Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. Now they are mostly used for electric power generation. They harness a clean and renewable energy...
. Recognized as one of the fathers of hydroelectric power, he was awarded the Elliott Cresson Medal
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...
during his lifetime and recently was inducted into the National Inventors Hall of Fame
National Inventors Hall of Fame
The National Inventors Hall of Fame is a not-for-profit organization dedicated to recognizing, honoring and encouraging invention and creativity through the administration of its programs. The Hall of Fame honors the men and women responsible for the great technological advances that make human,...
.
Early life and youth
Lester Allan Pelton was born in Vermilion, OhioVermilion, Ohio
Vermilion is a city in Erie and Lorain counties in Ohio, on the North Coast of the U.S.A. The population was 10,927 at the 2000 census. The current mayor is Eileen Bulan...
on September 5, 1829. His grandfather, Captain Josiah S. Pelton, who retired after a successful career at sea, had established his family and descendants prominently in the area. Lester's father was Allen Pelton, Josiah's youngest son; his mother was Fanny Cuddeback, she of another locally prominent family. As a youngster Lester worked on the Pelton family farm and attended the Cuddeback School.
In 1850, young Pelton joined a local party of males and emigrated from Ohio to participate in the California gold rush
California Gold Rush
The California Gold Rush began on January 24, 1848, when gold was found by James W. Marshall at Sutter's Mill in Coloma, California. The first to hear confirmed information of the gold rush were the people in Oregon, the Sandwich Islands , and Latin America, who were the first to start flocking to...
. But he was not successful as a miner, and for a time he fished the Sacramento River
Sacramento River
The Sacramento River is an important watercourse of Northern and Central California in the United States. The largest river in California, it rises on the eastern slopes of the Klamath Mountains, and after a journey south of over , empties into Suisun Bay, an arm of the San Francisco Bay, and...
and sold his catch locally; and he worked in woodmilling and carpentry. In 1860, after the gold strikes in the nearby Sierra Nevada he relocated to Camptonville
Camptonville, California
Camptonville is a small town and census-designated place located in northeastern Yuba County, California. The town is located northeast of Marysville, off Highway 49 between Downieville and Nevada City. It is located on a ridge between the North Fork and Middle Fork of the Yuba River, not far...
—near the Yuba River
Yuba River
The Yuba River is a tributary of the Feather River in the Sacramento Valley of the U.S. state of California. It is one of the Feather's most important branches, providing about a third of its flow. The main stem of the river is about long, and its headwaters are split into North, Middle and South...
and the California Mother Lode
Mother Lode
Mother lode is a principal vein or zone of veins of gold or silver ore. The term probably came from a literal translation of the Spanish veta madre, a term common in old Mexican mining...
country—where he made his living as a millwright
Millwright
A millwright is a craftsman or tradesman engaged with the construction and maintenance of machinery.Early millwrights were specialist carpenters who erected machines used in agriculture, food processing and processing lumber and paper...
and carpenter
Carpenter
A carpenter is a skilled craftsperson who works with timber to construct, install and maintain buildings, furniture, and other objects. The work, known as carpentry, may involve manual labor and work outdoors....
. 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 equiment and operations in California's gold rush country. Following are summary descriptions of the local technology observed by Pelton, and of the science by which the Pelton wheel extracts kinetic energy from a coursing mountain stream:Steam-heat powered much of local mining activities but required a lot of wood for fuel; nearby forests were routinely decimated. Turbine water wheel
Water wheel
A water wheel is a machine for converting the energy of free-flowing or falling water into useful forms of power. A water wheel consists of a large wooden or metal wheel, with a number of blades or buckets arranged on the outside rim forming the driving surface...
s also were used to supply power, but these were inefficient in converting the kinetic energy of mountain streams to horsepower. Further, 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
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 the Mother Lode. Samuel N. Knight developed a high...
at nearby Sutter Creek
Sutter Creek, California
Sutter Creek 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...
). 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 consolidatd 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 (i.e., high energy) sites. Before Pelton, almost all water turbines were reaction machines powered by water pressure, while Pelton's wheel was powered by the kinetic energy
Kinetic energy
The kinetic energy of an object is the energy which it possesses due to its motion.It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes...
of a high velocity
Velocity
In physics, velocity is speed in a given direction. Speed describes only how fast an object is moving, whereas velocity gives both the speed and direction of the object's motion. To have a constant velocity, an object must have a constant speed and motion in a constant direction. Constant ...
water-jet which could be conveniently developed from a small mountain stream.
(The Pelton design can be approximated by cupping both hands upward then bringing them together, aligning the fingernails 'back-to-back' to represent the splitter vane between the cupped hands. The split double cup, also called the split bucket, may be seen here
Pelton wheel
The Pelton wheel is an impulse turbine which is among the most efficient types of water turbines. It was invented by Lester Allan Pelton in the 1870s. The Pelton wheel extracts energy from the impulse of moving water, as opposed to its weight like traditional overshot water wheel...
; or here—showing the original Pelton model at the original site of manufacture, Miners Foundry - Allans (sic) Machine Shop, Nevada City, California.)
Building the Pelton wheel
In the late 1870s Pelton modeled, tested and manufactured his first turbine wheel—dubbed the Pelton Runner—at the Miners FoundryMiners Foundry
The Miners Foundry is located at 325 Spring Street, Nevada City, California, USA...
in Nevada City, California
Nevada City, California
-2010:The 2010 United States Census reported that Nevada City had a population of 3,068. The population density was 1,399.7 people per square mile . The racial makeup of Nevada City was 2,837 White, 26 African American, 28 Native American, 46 Asian, 0 Pacific Islander, 40 from other races,...
.In 1878, at the Mayflower Mine in Nevada City, he installed the first operational Pelton wheel. At that time the Knight Foundry
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 the Mother Lode. Samuel N. Knight developed a high...
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
Grass Valley, California
-2010:The 2010 United States Census reported that Grass Valley had a population of 12,860. The population density was 2,711.3 people per square mile . The racial makeup of Grass Valley was 11,493 White, 46 African American, 208 Native American, 188 Asian, 9 Pacific Islander, 419 from other...
, 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 normal lowflow conditions in a mountain stream. In 1887 a miner attached Pelton's wheel to a dynamo
Dynamo
- Engineering :* Dynamo, a magnetic device originally used as an electric generator* Dynamo theory, a theory relating to magnetic fields of celestial bodies* Solar dynamo, the physical process that generates the Sun's magnetic field- Software :...
and produced the first hydroelectric power in the Sierra Nevada.
Pelton patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
ed his wheel as well as his novel design of the double cup, 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 on March 14, 1908, at age 78; he was buried at his family site in Vermilion, OhioVermilion, Ohio
Vermilion is a city in Erie and Lorain counties in Ohio, on the North Coast of the U.S.A. The population was 10,927 at the 2000 census. The current mayor is Eileen Bulan...
. His Pelton Runner design is still used today to produce hydroelectric power in the United States and around the world. Later designs such as the Turgo turbine
Turgo turbine
The Turgo turbine is an impulse water turbine designed for medium head applications. Operational Turgo Turbines achieve efficiencies of about 87%...
, first patented in 1919, and the Banki turbine
Banki turbine
A cross-flow turbine, Banki-Michell turbine, or Ossberger turbine is a water turbine developed by the Australian Anthony Michell, the Hungarian Donát Bánki and the German Fritz Ossberger. Michell obtained patents for his turbine design in 1903, and the manufacturing company Weymouth made it for...
were inspired by the Pelton wheel.
In 1895 The Franklin Institute, Philadelphia, US, awarded Lester Pelton the Elliott Cresson Medal
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...
—now renamed the Benjamin Franklin Medal
Benjamin Franklin Medal (Franklin Institute)
The Benjamin Franklin Medal is a science and engineering award presented by the Franklin Institute, of Philadelphia, PA, USA.-Laureates:*1998 - Emmanuel Desurvire *1998 - Robert B. Laughlin *1998 - David N. Payne...
—for his accomplishments of invention in technology. Pelton was inducted into the National Inventors Hall of Fame
National Inventors Hall of Fame
The National Inventors Hall of Fame is a not-for-profit organization dedicated to recognizing, honoring and encouraging invention and creativity through the administration of its programs. The Hall of Fame honors the men and women responsible for the great technological advances that make human,...
in 2006. There are memorials and monuments celebrating Pelton and the Pelton Runner mounted in Camptonville, California
Camptonville, California
Camptonville is a small town and census-designated place located in northeastern Yuba County, California. The town is located northeast of Marysville, off Highway 49 between Downieville and Nevada City. It is located on a ridge between the North Fork and Middle Fork of the Yuba River, not far...
, in the Miners Foundry
Miners Foundry
The Miners Foundry is located at 325 Spring Street, Nevada City, California, USA...
in Nevada City, California
Nevada City, California
-2010:The 2010 United States Census reported that Nevada City had a population of 3,068. The population density was 1,399.7 people per square mile . The racial makeup of Nevada City was 2,837 White, 26 African American, 28 Native American, 46 Asian, 0 Pacific Islander, 40 from other races,...
, and at the Smithsonian Museum in Washington D.C., among other sites.