Who invented solar cells

Physics flourishes in the midth century with experiments in electricity, magnetism, and the study of light, among other breakthroughs. The basics of solar energy are part of that discovery, as inventors and scientists lay the groundwork for much of the subsequent history of the technology. His studies of light and electricity inspire later developments in photovoltaics. The photovoltaic effect is the key to solar PV technology.

A combination of physics and chemistry, the photovoltaic effect occurs when an electric current is created in a material when it is exposed to light. It has less than one percent efficiency in converting solar radiation to electricity.

PTC is still used in solar thermal power stations. The company soon fails. The emergence of modern theoretical physics helps create a foundation for a greater understanding of photovoltaic energy. Quantum physics's descriptions of the subatomic world of photons and electrons unveil the mechanics of how packets of incoming light disrupt electrons in silicon crystals in order to generate electric currents.

This becomes the basis for creating semiconductor wafers still used in electronics, including solar cells. Serious research into the development of solar technology, based on the invention of monocrystalline silicon solar cells, leaves the laboratory. Like many other technologies, it emerges out of research conducted for the U.

These uses demonstrate the effectiveness of solar energy, though most of the technology is still too expensive to be commercialized. It can operate during both daylight and darkness. Charles Fritts was the first person to generate electricity using solar panels—in —but it would be another 70 years before they became efficient enough to be useful.

Those three pioneers stood on the sometimes-overlooked shoulders of their Bell Labs predecessor Russel Ohl, who discovered how silicon crystals acted as semiconductors when exposed to light.

The energy crisis of the early s spurs the first commercialization of solar technology. Calvin S. Fuller at work diffusing boron into silicon to create the world's first solar cell.

Solar cells, which convert sunlight into electrical current, had their beginnings more than a hundred years ago, though early solar cells were too inefficient to be of much use. In April, , researchers at Bell Laboratories demonstrated the first practical silicon solar cell. The story of solar cells goes back to an early observation of the photovoltaic effect in Several decades later, in , Willoughby Smith, an English engineer, discovered the photoconductivity of selenium while testing materials for underwater telegraph cables.

In , American inventor Charles Fritts made the first solar cells from selenium. Some research on selenium photovoltaics continued for the next several decades, and a few applications were found, but they were not put to widespread use.

The next major advance in solar cell technology was made in by Russell Shoemaker Ohl, a semiconductor researcher at Bell Labs. He had been investigating some silicon samples, one of which had a crack in the middle. He noticed that in this particular sample, current flowed through this sample when it was exposed to light.

This crack, which had probably formed when the sample was made, actually marked the boundary between regions containing different levels of impurities, so one side was positively doped and the other side negatively doped. Adams and R. Day worked on this aspect and observed the same effect in solidified selenium. Besides, they also published a paper on the selenium cell. Following these two, several scientists worked on this to understand more about selenium and photovoltaic effect.

It was the American inventor Charles Fritts who built the first genuine solar cell. He built it by placing a layer of selenium on a metal plate and covering it with a thin layer of gold.

Though a couple of scientists were curious about this invention, most scientists paid little attention. Perhaps, so little was their knowledge on solar energy. In those times, since there were better technologies to generate electricity, the PV technology failed to attract the masses.

In fact, in modern terms, it was a flop. It was Albert Einstein who made a major breakthrough in the development of solar technology. He set his mind to understand how light could possibly create electricity when it hit a metal. Einstein knocked down everyone with his terrific explanation. He explained that light was made of tiny packets of energy called photons.

He also elaborated on how photons wiggled like waves as they sped along. Einstein proposed that these photons are more powerful in ultraviolet light that in the normal light that we can see. He also added that these photons have enough energy to knock the loose electrons off some materials like silicon and selenium. These knocked out free electrons move through wires as electric current or electricity. After testing these ideas, many scientists were convinced.

His theoretical calculations of its potential were encouraging. An ideal unit, Chapin figured, could use 23 percent of the incoming solar energy to produce electricity. However, he set a goal of obtaining an efficiency of nearly 6 percent, the threshold that engineers of the time felt it was necessary to reach if photovoltaic cells were to be seriously regarded as electrical power sources.

Chapin, doing most of the engineering, had to try new materials, test different configurations, and face times of despair when nothing seemed to work. At several junctures, seemingly insurmountable obstacles arose. To build such a cell required collaboration with Fuller. Adding boron to the top of the cell permitted better photon harvesting by allowing for good electrical contact on the silicon strips while keeping the p-n junction close to the surface.

Chapin finally triumphed, reaching his 6 percent goal. Proud Bell executives presented the Bell Solar Battery to the press on April 25, , displaying a panel of cells that relied solely on light power to run a inch Ferris wheel. The press took notice. Engineers are dreaming of silicon-strip powerhouses.

From the book Let It Shine. Reprinted with permission from New World Library.