Solar power has always fascinated mankind. The sun is an eternal power source and nothing on this earth comes to close to the majesty of the sun. Even our fables were centered on how harnessing the power of the sun could give man a power unmatched by none. The earliest reference to solar power is from the 3rd century, when supposedly Archimedes fought off Roman ships by using a contraption (similar to a magnifying glass) to set them on fire. This story maybe only a story but it is the earliest record of man flirting with the power of solar.
True success in harnessing solar power came centuries later. In the 17th century a Swiss physicist and Alpine explorer (quite a unique combination) invented the first working solar oven. Horace de Saussure’s oven was constructed from 5 layers of glass and measured around 12 inches tall. The idea was ingenious. The sunlight passed through the glass before being absorbed the black lining and turned into heat. The heat was then absorbed the glass box and temperatures in the box reached up to 87.5 degrees Celsius.
1839 – The Photovoltaic Effect
This is the year in which we can trace the beginning of our ambition to generate electricity to run our homes and cars. Edmond Becquerel (born in Paris in 1820) discovered that when two electrodes are placed in an electrolyte (electricity-conducting solution), a voltage developed when sunlight fell upon the electrolyte. This was the moment when the basic principle of solar power was discovered.
1873 – Uncovering the potential of Selenium
The discovery of selenium is credited to Jacob Berzelius and Johan Gottlieb. They discovered selenium in 1817, but it was not until 1873 that selenium’s potential was discovered. Willoughby Smith, an English electric engineer, discovered that selenium was photoconductive. This was an accidental discovery that helped mankind progress leaps. What Willoughby was actually doing was the development of a method for continually testing underwater telegraph cables as they were being laid. He chose selenium rods as semi-conductors. Selenium was considered, but Willoughby noticed that his results when using selenium were inconsistent. In seeking the contributing factor to this inconsistency, he realized that exposure to light affects the conductivity of selenium. He then published his findings.
1876 – Producing Electricity
1876 was the year when the first consistent current was produced using light. Professor William Grylls Adams and his student Richard Evans Day found in 1876 that selenium produced electricity when exposed to light. They attached platinum electrodes to selenium and observed that a consistent current was being produced when exposed to light. However the current was not enough to power anything important but the possibility of generating electricity through sunlight had been proven.
1883 – The world’s first Solar Cell
Charles Fritts, an American inventor, developed the first working solar cell in 1883. He applied selenium to a thin layer of gold. However, this method was inefficient as it only achieved 1% efficiency, making it impractical for general use. But it was a start!
1904 – Einstein’s paper on ‘Light and Electrons’
Einstein’s paper would lay the basis on which much would be achieved. Titled “On a Heuristic Viewpoint Concerning the Production and Transformation of Light”, it explained for the first time the relationship between light and electrons. It was this paper that led him to win the Nobel Prize in 1921.
The importance of this paper was that in 1916 Robert Millikan proved experimentally that Einstein’s theory of photoelectric effect worked.
1918 – Accidental Crystals
It was proven that electricity could be generated without heat and moving parts. However an efficient cell was still not discovered. 1918 laid the groundwork for that. Jan Czochralski, a Polish scientist discovered the method of creating single crystal silicon. His discovery not only helped solar power be what it is but also contributed towards the creation of transistors for microprocessor chips.
1954 – The creation of the Solar Cell; the major breakthrough
It took three researchers to finally discover silicon solar cells. Daryl Chapin, Calvin Fuller, and Gerald Pearson got together in 1954 and made a solar battery which worked at an efficiency of 6%. The first solar cell was the size of a small coin. Though its efficiency did not make it commercially viable, it has served as the basis of solar cell development since.
Late 1950s – The Era of Solar Cells
This was the era or continuously improving solar cells. Hoffman electronics led this race by starting with 8% efficient cells in 1957 and eventually making a 14% efficient commercially violable cell in 1960.
1950s and 60s – The Space Race
Since the dawn of time man has looked to the heavens with hope and wonder. The space race pushed mankind to new limits. We needed perpetual source of energy and thanks to the race we achieved solar cells which could achieve up to 14 watts.
1970s – The Era of Commercialization
We had successfully made solar cells, but they were too expensive. It was in the 70s that we finally moved to commercialization. Dr. Elliot Berman backed by Exxon Corp brought the cost down from USD 100 per watt to just USD 20.
1972 – Powering houses through solar energy
It was in 1972 that the idea of generating electricity in the morning to run the house and feed in the excess to the grid was developed. This is the model we still use today.
1978 – Solar energy becomes a viable commercial venture
The first form of tariff for the surplus energy being fed into the grid was implemented under President Jimmy Carter, after signing the National Energy Act.
It was from 1978 onwards that solar had begun to enter the mainstream. And right now it is the future of not just energy for households and commercial concerns but also personal vehicles and overall transportation. Right now governments are pushing lowered emissions, but with Telsa’s groundbreaking progress in electric cars, solar energy will help to further revolutionize the transportation industry by leading to a scenario with zero emissions. And this is not a far-off future. Germany is one of the countries where the majority of the electricity is being generated via a mix of renewable energy sources so even in present day electric cars there are running on renewable energy. It is only a small matter of time (relatively) till solar energy combined with other renewable sources makes combustion based energy methods extinct.
2016 to the future