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US Solar Industry

History of Pre-Modern Solar Development and Usage

Project: US Solar Industry
Open-Content project managed by matt, Derek, KJF, mtuck

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An ancient Roman bathhouse (thermae). The Baths of Diocletian could hold up to 3,000 bathers.An ancient Roman bathhouse (thermae). The Baths of Diocletian could hold up to 3,000 bathers. [Source: Crystalinks (.com)]Roman bathhouses use the sun to warm the chambers. In many areas such as Zippori, an ancient Roman city in what is now Israel, the sunlight is usually let in through south-facing windows. By the 6th century, sunrooms in houses and public buildings are so commonplace that the Justinian Code creates “sun rights” to ensure the citizens’ right to access sunlight. (Hebrew University of Jerusalem Institute of Archaeology 6/26/1998; US Department of Energy 2002 pdf file)

A portion of an Anasazi cliff village in Manitou Springs, Colorado.A portion of an Anasazi cliff village in Manitou Springs, Colorado. [Source: Examiner (.com)]The Anasazi, the ancient Native American tribe that predated the Pueblo, live in south-facing cliff dwellings that capture the winter sun and heat their homes. (US Department of Energy 2002 pdf file)

Swiss scientist Horace de Saussure builds the world’s first solar collector. It is later used by Sir John Herschel to cook food during his South Africa expedition in the 1830s. (US Department of Energy 2002 pdf file)

Robert Stirling applies for a patent for his “Economiser” at the Chancery in Edinburgh, Scotland. Stirling, a minister in the Church of England, is an amateur scientist and inventor. His “Economiser” is a “heat engine” that uses the sun’s thermal energy to produce small amounts of power. Lord Kelvin later uses one of Stirling’s working models to demonstrate the value of solar power in his university classes. The “Economiser” is later used as part of the design of the “Dish/Stirling System,” a solar thermal electric technology that concentrates solar energy to produce power. (US Department of Energy 2002 pdf file)

French scientist Edmond Becquerel, 19 years old, discovers the photovoltaic effect while experimenting with an electrolytic cell made up of two metal electrodes placed in an electricity-conducting solution. Becquerel’s experiment proves that heightened amounts of electricity can be generated when the cell is exposed to sunlight. He coins the term “photovoltaic effect” to describe his finding. Basically, the photovoltaic effect (PV) occurs when the energy from photons strikes a semiconducting material such as silicon or platinun, and transfers its energy to an atom of the semiconducting material. The energized electron then escapes its bond and generates an electric current. The “gap” created by the escaped electron works with the electron to create the current. (US Department of Energy 2002 pdf file; Mr. Solar 2012)

French mathematician August Mouchet conceives the solar-power steam engine. Mouchet and his assistant Abel Pifre build the world’s first true solar-powered engines and use them for a number of applications. The Mouchet engine is the predecessor of modern parabolic dish collectors. (US Department of Energy 2002 pdf file)

Scientist Willoughby Smith discovers the photoconductivity of selenium. Photoconductivity can be defined as an optical and electrical phenomenon in which a material becomes more electrically conductive due to the absorption of electromagnetic radiation such as visible light, ultraviolet light, infrared light, or gamma radiation. Three years later, William Grylls Adams and Richard Evans Day discover that selenium produces electricity when exposed to light. The cells constructed by the two scientists do not convert enough sunlight to power electrical equipment, but they do prove that a solid material can change light into electricity without heat or moving parts. (US Department of Energy 2002 pdf file; Allison June Barlow Chaney 2011)

Samuel P. Langley invents the bolometer. His device measures light from starlight and from the sun’s rays. It is constructed of a fine wire connected to an electric circuit. When starlight or sunlight falls on the wire, the wire becomes slightly warmer, increasing the electrical resistance of the wire. (US Department of Energy 2002 pdf file)

American inventor Charles Fritts describes the first solar cells made from selenium wafers. Fritts hopes that his cells might compete with the coal-fired power plants of Thomas Edison, but Fritts’s cells operate at less than one percent efficiency, far below the threshold for practical applicability. (US Department of Energy 2002 pdf file; American Physical Society 2013)

German scientist Heinrich Hertz discovers that ultraviolet light alters the lowest voltage capable of causing a spark to jump between two metal electrodes. (US Department of Energy 2002 pdf file)

Inventor Clarence Kemp of Baltimore patents the first commercial solar water heater. Kemp, who sells cutting-edge home heating equipment, combines the older practice of exposing metal tanks to sunlight with the scientific principle of the “hot box” (see September 27, 1816), thus increasing the tanks’ capability of collecting and retaining heat. He calls his invention the “Climax.” He first markets it to Eastern “gentlemen” whose wives have gone on holiday for the summer, leaving them to their own devices. Kemp sells his heaters by claiming that they will reduce the effort needed to perform housekeeping duties, especially for men unaccustomed to lighting the gas furnace or stove to heat water. Later, Kemp will find a brisk market for his Climax heaters in warmer states such as California. By 1897, a third of the households in Pasadena will use the Climax to heat water in their homes. (California Solar Center 2001; US Department of Energy 2002 pdf file)

Physicist Albert Einstein publishes a paper on the photoelectric effect. Unfortunately for the paper, another paper he publishes, on the theory of relativity, draws far more attention. In 1921, he will win the Nobel Prize for his work on the photoelectric effect. (US Department of Energy 2002 pdf file)

Despite the initial success of the “Climax” solar water heater (see 1891), consumers are dissatisfied with a major drawback of the heater: its inability to keep the water it heats hot for more than a few hours. Inventor William J. Bailey of the Carnegie Steel Company separates the solar heater into two components: a heating element exposed to the sun and an insulated storage unit kept inside the home. Bailey’s invention allows families to have solar-heated water day and night, and even into the next morning. The device keeps water in narrow pipes instead of a large tank, allowing the water to retain its heat longer and for less water needing to be exposed to the sun at any given time. Bailey calls his invention the Day and Night, and by 1918 sells over 4,000 of the heaters. (California Solar Center 2001; US Department of Energy 2002 pdf file)

Scientist Robert Millikan provides experimental proof of the photoelectric effect. (US Department of Energy 2002 pdf file)

By the 1930s, the solar water heater industry is essentially killed off in California by discoveries of huge natural gas reserves in the Los Angeles basin. William Bailey, who has grown rich selling his solar-powered water heaters (see 1909-1918), adapts his design for a thermostatically-controlled gas water heater. His Day and Night Solar Water Heater does quite well in Florida, where a building boom has brought in an influx of new residents, many of whom have to pay high rates for hot water. Florida’s semi-tropical climate and its housing boom creates an excellent selling environment for Bailey’s “hybrid” water heater. By 1941, over half of Florida residents heat their water with solar or solar-gas heaters. However, declining energy rates after World War II combined with an aggressive effort by Florida Power and Light to increase electrical consumption by offering electric water heaters at bargain prices brings the state’s solar water heater industry to its knees. (California Solar Center 2001)

In a conversation with fellow inventors and entrepreneurs Harvey Firestone and Henry Ford, Thomas Edison says of renewable energy sources: “We are like tenant farmers chopping down the fence around our house for fuel when we should be using nature’s inexhaustible sources of energy—sun, wind, and tide.… I’d put my money on the sun and solar energy. What a source of power! I hope we don’t have to wait until oil and coal run out before we tackle that.” (US History 2013; About Thomas Edison 8/19/2013)

Semiconductor researcher Russell Shoemaker Ohl of Bell Laboratories is poring over silicon samples, one of which has a crack in the middle. Electrical current flows through the cracked sample when exposed to light. The crack, likely formed when the sample was made, actually marks the boundary between regions containing different levels of impurities, so one side is positively “doped” and the other negatively doped. Ohl has inadvertently created a “p-n junction,” the basis of a solar cell. When an excess positive charge builds up on one side of the p-n barrier, and a similar excess charge builds up on the other, negatively charged side, an electric field is created. The cell can be hooked up into a circuit, and incoming photos striking the cell can “kick” electrons loose and start a current flowing. Ohl patents the solar cell, which operates at about one percent efficiency. (American Physical Society 2013)

In the United States, scarce energy due to the war effort produces a high demand for passive-solar buildings. The Libbey-Owens-Ford Glass Company publishes a book called Your Solar House, profiling 49 of the nation’s best-known solar architects. (US Department of Energy 2002 pdf file)

The Greek navy recreates a legendary feat by the Greek scientist Archimedes, who is said to have used bronze shields to focus sunlight and set fire to wooden ships belonging to the Roman navy. Archimedes’s action took place around 212 B.C. The Greek navy recreates the experiment and sets fire to a wooden boat at a distance of 50 meters. (US Department of Energy 2002 pdf file)

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