The History Of Solar Panels

Years before the 22nd of April 1970, when the world celebrated the first Earth Day and spurred widespread concern for the environment and the need to conserve the environment, scientists had already begun to realize tangible results in solar energy discovery and innovations.

For instance, the first milestone was the discovery of the photovoltaic effect in 1839 by Edmond Becquerel, a young physicist based in France. The photovoltaic effect was based on a series of processes that could generate voltage or electrical current from light or radiant energy.

Years later, the photovoltaic effect encouraged Augustin Mouchot, a French mathematician to dig further to explore the photovoltaic subject. Augustin Mouchot started in the 1860s by patenting the solar-powered engines, thereby motivating other inventors in France and the United States to jump on the bandwagon, and by early 1888, most solar-powered device inventions in Europe and the US had been patented. 

Simultaneously, in 1883, a New York inventor called Charles Fritts has made the first solar cell using selenium and a strip of gold. According to Fritts, using selenium helped to in generating a “continuous and constant” current which had “considerable force”. While most modern solar cells operate with an energy efficiency of between 15 and 20%, the first solar cell had an energy conversion rate of only 1 to 2%. 

Fritts’ low impact solar cell marked the start of other photovoltaic solar panel innovations in the US. According to Alessandro Volta, an inventor in electricity and power, a chemist and physicist with an Italian name, the term photovoltaic (also be referred to as photoelectric) was used to refer to the process of converting light energy to electricity.

Years later in 1888, Edward Weston was granted two patents for solar cells, i.e. U.S. Patent 389,124 and U.S. Patent 389,425. The proposal in the two patents was to convert radiant energy received from the sun into electric energy, or into mechanical energy via electrical energy. In this process, sunlight was directed through a lens (f) and focused on the solar cell (a). A solar cell was an electrical device made of bars and different metals that transformed heat energy into electrical energy.

The light caused the solar cell to heat up, releasing electrons and causing the flow of current, thereby converting light energy into electricity. This process is the exact reverse of how an incandescent light bulb works – by taking in electric energy and converting it to heat energy to burn and give off light.

In 1888, the same year, Aleksandr Stoletov, a Russian scientist made the first solar cell using the photoelectric technology. For this invention, the light was focused on a certain material to cause the release of electrons. This process was first studied by a German scientist and researcher called Heinrich Hertz. Hertz’s research showed more power could be generated using ultraviolet light instead of the visible light. In modern times, solar cells rely on the photoelectric effect to transform light into electrical power. 

In 1894, Melvin Severy, an American pioneer received patents 527,377 meant for “an apparatus for mounting and operating thermopiles" and another 527,379 for “an apparatus for creating electricity using solar heat.” Effectively, the two patents were the initial solar cells working using the photoelectric effect.

The first patent aimed at generating electricity by harnessing solar heat and focusing it on a thermo-pile. It envisioned a device that could give off a stable electrical current every day and throughout the yearly movement of the sun. This meant users did not have to shift the thermopile according to the direction of the sun. The other patent from 1889 was designed to use the sun’s heat energy to generate electricity to heat or light or power electrical equipment. 

The thermo-piles (called solar cells in today’s literature) were set on a standard to enable them to be moved vertically and remain turntable for easy shifting while on a horizontal plane. According to the patent, combining these two movements ensured the face of the pile could be placed well opposite the sun throughout the day and all seasons of the year.

About ten years later, Harry Reagan, an American inventor, got patents for thermal batteries. Essentially, they were structures designed to store and give out thermal energy. They were to gather and store heat using a huge solid mass with capable of heating up and giving out energy. Note, it does not store electric energy but heat energy. Nonetheless, this system technology is nowadays used to create electric energy using conventional turbines.

Later in 1897, Reagan received a U.S patent 588,177 for the use of solar energy in thermo-batteries. While applying for this patent, Reagan claimed the invention consisted an original construction of devices where the rays of the sun are focused and absorbed to heat the thermo-batteries. The objective of the design was to focus and direct the rays of the sun on a singular set of connections of the thermo-battery. At the same time, the invention included cooling devices on certain connections of the thermo-battery to prevent the device from overheating. This device was meant to collect, store and distribute the solar heat. 

In 1913, William Coblentz, an inventor based in Washington DC was granted patent 1,077,219 for a device called a thermal generator. Its function was to create an electrical current capable to carrying out “useful” work. According to the patent, Coblentz wanted the device to have a strong body construction while being affordable to most people. The thermal generator may not have a direct affiliation to a solar panel, but it greatly supported the conversion of heat energy directly into power for heating or cooling purposes.

By around 1950, Bell Laboratories discovered that silicon, a type of semiconductor material, was more efficient than selenium. Bell Laboratories succeeded in making a solar cell with 6% efficiency of energy conversion. Notably, Daryl Chapin, Calvin Fuller, and Gerald Pearson were the inventors at Bell credited with the silicon solar cell discovery and were sworn into the National Inventors Hall of Fame in 2008 for the great achievement.

However, despite its usefulness in transforming solar energy into electricity, the device remained pricey for most people. Even in the current times, silicon solar cells are still costly to manufacture when you have to install numerous cells for solar panel; it is more costly for the general public.

The University of Delaware is acknowledged for making one of the initial solar buildings called Solar One in 1973. The construction of the building included a mix of solar thermal and solar photovoltaic power. Instead of using solar panels, solar was used as an integral part of the rooftop.

Around 1970, the energy crisis happened in the United States occasioning Congress to take steps to make solar affordable and viable and to market its usage to the public. This was made possible by the passing of the Solar Energy Research, Development and Demonstration Act of 1974.

Following the success of the Solar One building, many people started viewing solar energy as a worthy alternative for their houses and other buildings. Later around the 1980s, the popularity and adoption of solar dipped due to a general price fall in the traditional forms of energy. However, in the decades that followed saw the federal government take a more central role in the research and development of solar energy. The government issued grants and tax favors to people who choose to invest in solar power systems.

As per the Solar Energy Industries Association, the US solar power industry has grown at an average annual rate of 50% over the last 10 years. This growth has largely been attributed to the Solar Investment Tax Credit passed in 2006. This enactment made solar installations cheaper by cutting the cost by more than 70%.

Bottom-line, finding ways to make solar cells a more viable and affordable power solution is more necessary than merely making solar panels look good and attractive. This is because, to many, the traditional solar panel set on most American rooftops is not a very attractive real estate hack. The solar panels sometimes seem an eyesore to the neighbors, which can be an uncomfortable issue for homeowners associations to handle. However, the benefits of solar power are immense and significant.

The goal is to strike a balance between achieving good-looking and economically viable solar technology like the Building-Applied Photovoltaic (BAPV). This solar cell technology is discreet and can be easily integrated into a building’s roofing tiles, ceramic or glass façades.

Some of the companies that have received patents to make the newer and more discreet models of solar cells include Solus Engineering, Enpulz, SolarCity Corporation, Guardian Industries Corporation, United Solar Systems, and Tesla following their merger with SolarCity.

All the modern-day patents for solar cells include photovoltaic systems designed to convert light into electricity using semiconductors such as silicon. The evolution story of the solar panel and the solar industry dates a long while back, and these patents show the industry’s technology is still growing and improving towards utmost energy