Before the first Earth Day was celebrated on April 22, 1970, creating awareness of the environment and the need for environmental protection, Scientists made their first breakthroughs in solar energy. The process began in the hands of Edmond Becquerel, a young scientist in France who, in 1839, discovered and observed a phenomenon of photovoltaic— a method that produces an electric current or voltage when exposed to light or radiation. In the following decades, French mathematician Augustin Mouchot was impressed by the work of the physicist. He began to register patents for solar-powered motors in the early 1860s. Between France to the U.S., inventors were attracted by the mathematician’s patents and applied for patents on solar-powered machines from 1888.
Take a gentle look back to 1883. New York inventor Charles Fritts invented the world’s first solar-powered cell covering selenium with a fine coating of gold. Fritts stated that the selenium-coated module generated electrical electricity “that is continuous, constant, and of considerable force.” The cell had a conversion rate of 1 and 2 percent. Modern solar cells operate with an efficiency between 15 and 20 percent. That’s why Fritts developed an environmentally friendly solar cell, but it marked the beginning of America’s photovoltaic solar panel revolution. The term is named after the Italian scientist, physicist, and pioneer of power and electricity, Alessandro Volta; photovoltaic is the technical term used for changing light energy into electricity and is often used interchangeably with photoelectric.
Just a few years later, in 1888, the inventor Edward Weston received two patents for solar cells: U.S. Patent 389,124 and U.S. Patent 389,425. In both patents, Weston proposed “to transform radiant energy derived from the sun into electrical energy, or through electrical energy into mechanical energy.” Light energy is concentrated by lenses (f) on the solar cells (a), “a thermopile (an electronic device that converts thermal energy into electrical energy) composed of bars of dissimilar metals.” The light rays heat the solar cell, causing electrons to escape and currents to move. In this case, light produces heat, which generates electricity. This is precisely how an incandescent bulb functions, which converts electricity into heat, which has light.
The same year, a Russian scientist named Aleksandr Stoletov created the first solar cell based on the photoelectric effect. This is the process where light hits the material, which releases electrons. The phenomenon was first discovered by the German scientist Heinrich Hertz. Through his studies, Hertz discovered that more power is generated through ultraviolet light than visible light. Solar cells today use an effect called photoelectric to turn sunlight into energy. In 1894, American scientist Melvin Severy was granted patents 527,377 for an “Apparatus for mounting and operating thermopiles” and 527,379 for an “Apparatus for generating electricity by solar heat.” The two patents were both early solar cells, based on the research that led to the development of the photoelectric phenomenon. The first produced “electricity by the action of solar heat upon a thermo-pile.” It could generate an unchanging electric current throughout the annual and daily motions of the sun, which meant that no one had to adjust the thermopile to the sun’s movement. Severy’s patent number two, from 1889, also aimed at using solar energy to generate electricity for light, heat, and power. These “thermos piles,” or solar cells, as we refer to them in the present, were placed on a standard that allowed them to operate in a vertical direction and with a turntable, allowing them to move in the horizontal plane. “By the combination of these two movements, the face of the pile can be maintained opposite the sun all times of the day and all seasons of the year,” according to the patent.
A decade later, American creator Harry Reagan received patents for thermal batteries, essentially structures that can store and discharge heat energy. Thermal batteries were developed to store and collect heat through a vast mass that can heat to release energy. It doesn’t keep electricity. However, it holds “heat” technologies today use this technology to produce electricity through traditional turbines. It was in 1897 that Reagan received U.S. patent 588,177 for the “application of solar heat to thermo batteries.” In the patent’s claims, Reagan said his invention contained “a novel construction of apparatus in which the sun’s rays are utilized for heating thermo-batteries, the object being to concentrate the sun’s rays to a focus and have one set of junctions of a thermo-battery at the focus of the rays, while suitable cooling devices are applied to the other junctions of said thermo-battery.” The inventor’s invention was collecting solar heat, storing it, and distributing it to others. Heat in the event of a need.
It was 1913 when William Coblentz of Washington, D.C., was granted Patent 1,077,219 for a “thermal generator,” a device that utilized light radiation “to generate an electric current of such a capacity to do useful work.” The inventor also wanted the invention to be affordable and durable construction. Although the patent was not intended for a solar panel, the thermal generators were created to convert energy directly into electricity or transform the energy into power to heat and cooling.
In the 1950s, Bell Laboratories realized that semiconducting substances like silicon had higher efficiency than selenium. They created solar cells that were six percent more efficient. Three inventors, Daryl Chapin and Calvin Fuller, along with Gerald Pearson ( inducted into the National Inventors Hall of Fame in 2008), were the minds behind Bell Labs’ silicon solar cells in Bell Labs. Although it was thought to be the first viable device for making electricity from solar energy, the price was prohibitive for most people. Silicon solar cells are costly to manufacture, and when you combine several cells to make solar panels, they are more expensive for consumers to buy. The University of Delaware established one of the first solar structures, “Solar One,” in 1973. The building was built using solar photovoltaic and solar thermal energy. The building did not use solar panels; instead, solar power was integrated into the roof.
During this period in the 1970s, an energy crisis erupted throughout the United States. Congress adopted the Solar Energy Research, Development, and Demonstration Act 1974. The federal government was more determined than ever ” to make solar viable and affordable and market it to the public.” After the introduction in 1974 of “Solar One,” people could see solar as an option for homes. In the 1980s, growth slowed because of the decline in energy costs for traditional sources. In the subsequent years, the federal government was more involved in research and development in the field of solar energy through tax incentives and grants to those using solar panels. According to the Solar Energy Industries Association, solar energy has seen an average annual increase of 50 percent in the United States over the past ten years, primarily due to the Solar Investment Tax Credit enacted in 2006. Solar installation is becoming more affordable due to costs for installation dropping by more than 70 percent over the last decade.
However, at least up to a point, the process of finding an affordable and sustainable energy source is more important than creating solar cells that are visually appealing or stunning. The traditional solar panels on American rooftops need to be more aesthetically pleasing and attractive. They’ve become a source of irritation for neighbors and a hassle for homeowners’ associations; however, the environmental benefits are significant. What’s the right balance? Nowadays, businesses are working toward more attractive and sophisticated solar technology, including BAPV or building-applied solar (BAPV). This type of discrete solar panel can be integrated into the roof tiles that are already in place or glass and ceramic facades of buildings.
Solus Engineering, Enpulz, Guardian Industries Corporation, SolarCity Corporation, United Solar Systems Solus Engineering, Enpulz, and Tesla (after the merger of their companies together with SolarCity) All have been granted patents for solar panels that can be less noticeable than the conventional solar panel. The patents all contain photovoltaic devices, which convert light into electricity with semiconducting materials like silicon. The solar panel and the technology have progressed a lot, and these patents demonstrate that technology is constantly improving in efficiency and aesthetics.