Trying to harness the sun’s energy for useful purposes has sparked the interest of many scientists for thousands of years and it still continues in today's times. Our star, "the sun", has been used a source of energy, not just by humans, but also by the many other life forms on earth. Plants use it to grow while many animals have found the sun's light to be their ultimate guide during the day. We, humans, have also utilized sun's many benefits even as cavemen. The more technological times demand more energy and we now have methods to convert solar energy to electrical energy.
Photovoltaics are devices that generate electricity from sunlight using the photovoltaic effect. This phenomenon was unknown to us until about two centuries ago and in this article, we will talk about how everything started.
- 700 BC: Fires from sunlight
- During the 700 BC, humans had figured out a way to make fire from sunlight by concentrating it with a magnifying glass.
- This method proved to be very helpful and started the journey of exploring the power of the sun.
- 1767: The first solar oven
- Centuries after human beings used the energy from the sun for primitive purposes, a more sophisticated progress was made with the solar oven.
- Horace de Saussure, a Swiss physicist, is the person who invented the first solar oven which has now become a common appliance found in many households as well as educational institutions.
- 1839: The photovoltaic effect is discovered
- Edmund Becquerel, a French physicist, was only 19 years old when he discovered that voltage is created when a material is exposed to light.
- This discovery laid the foundation for further progress.
- 1873: Photoconductivity in solid Selenium is discovered
- This is an important discovery by Willoughby Smith which led to the next steps.
- 1876: Generation of electricity from light
- Professor William Grylls Adams, accompanied by his student, Richard Evans Day, went ahead to explore Smith's discovery in 1873 and were the first to observe the flow of electricity in a cell based on Selenium plate when exposed to sunlight.
- 1883: the first design of a photovoltaic cell is laid
- Based on the progress in the prior years, American inventor, Charles Fritts, developed a design for the solar cells.
- His designs were based on the Selenium wafers.
- 1918: Here comes silicon
- Jan Czochralski, a Polish scientist, discovered a method to grow single crystal silicon which will now form the base of future solar cells.
- 1954: Finally, photovoltaics are here
- David Chapin, Calvin Fuller and Gerald Pearson of Bell Labs made the first photovoltaic cell which successfully converted solar energy into electrical power.
- The efficiency was 4 per cent originally which they pushed to 11 per cent later.
This is how it all began and the developments in technology continue as time goes on.