A Brief History of Solar Electric Systems
When most people think of solar electric systems, they think of state of the art technology at the cutting edge of modern science. However, the history for the solar panel goes back over 180 years. In 1839, a French scientist named Antoine César Becquerel, discovered photovoltaic effect. The photovoltaic effect involves the creation of a voltage in a material upon exposure to electro-magnetic radiation from sunlight.
This discovery took place while experimenting with an electrolytic cell made with two metal electrodes placed with an electrolyte solution; similar to the way a battery works today. Antoine-Cesar Becquerel discovered that when the electrolytic cells were exposed to light, it produced electricity. The more light he applied, the greater the amount electricity produced. In effect, Becquerel discovered a light activated battery. This type of battery is called a solar cell. A collection of solar cells placed in series or in parallel is called a solar panel. A collection of panels, along with the wiring and batteries to stored the converted energy comprise solar electric systems.
In 1883, almost 50 years after Becquerel’s discovery, Charles Fritts developed the world’s first solar cell using selenium coating sheets with a micro-thin layer of gold. The next 60 years saw many scientists and inventors continued to experiment with solar energy, both with private fund and corporate assistance. One such inventor named Clarence Kemp from Baltimore created and patented the first ever commercial solar energy powered water heater. In 1904, Albert Einstein published a thesis on photoelectric effect and received the Nobel Prize for his research.
While working for Bell Laboratories, an American inventor named Russell Ohl patented the first ever silicon solar cell in 1941. Bell Laboratories continued to build upon Ohl’s invention and in 1954 produced the first crystalline silicon solar panel. At the time, these solar cells reached a new level of efficiency achieving a 4% return on overall energy conversion. Over the next few years, scientists throughout the world built upon Bell Laboratories’ innovation and quickly developed solar cells producing 6% efficiency on overall energy conversion.
Research and development into solar electric systems grew by leaps and bounds and reached its first practical application at the dawn of the space age, more specifically, its use in space satellites. It was not practical to send satellites into space which depended on refueling or ran on traditional batteries which would eventually become exhausted. A new “permanent” power source was needed to allow satellites to stay in orbit indefinitely without needing any maintenance. Solar power fit that requirement perfectly. In 1958, NASA launched the Vangaurd Spacecraft, which became the first artificial satellite to reach Earth’s orbit and the first satellite to be powered by solar energy.
The United States was the first country to fund the large scale research and development of solar cells, which in 1980, yielded 20% efficiency. By 2000, American corporations had developed several solar cells capable of producing 24% efficiency. In 2008, Emcore Photovoltaics and Spectrolab announced that they’ve reached new levels of power by producing solar cell which yielded 28% efficiency.
There is no telling where the future of solar electricity will take us. However, as more and more applications employ the use of solar energy, both the cost and efficiency of solar cells will improve to encourage wide spread use. One day, solar electric systems may generate the majority of the energy required to sustain the ever increasing appetite of our modern technological societies.
