A Brief History of How We Harness the Sun
Every day, our sun provides a significant amount of energy.In fact, enough energy from the sun hits the Earth every hour to power our planet for an entire year! Since the 1800’s, scientists have wondered how we can harness this massive energy supply.
Today, the solar industry has become a leading source of renewable power generation as well as the #1 source of employment for the United States’ Electric Power Generation sector’s workforce. The roots of using solar energy for electricity start with discovery and have evolved through innovation. As new products, ideas, and methods are formed, these breakthroughs translate into greater cost efficiency, consumer benefits, and conveniences.
Let’s have a closer look at the history of solar power to better understand this evolution.
The invention of the solar photovoltaic effect
The photovoltaic effect, at its most basic, is the reaction of voltage and electric current inside a solar cell exposed to sunlight. This solar cell process generates the movement of electrons to solar panels, which convert sunlight to electricity.
In 1839, 19-year old French scientist Edmond Becquerel discovered the photovoltaic effect. He was fascinated with the phenomena of phosphorescence (the emission of light without heat). During his investigation of photochemical reactions, he began to understand the absorption of energy in the form of light, which led to his discovery of the photovoltaic effect. In the late 1860s, he published his findings, noting that “the voltage of the cell increased when its silver plates were exposed to the sunlight.”
In 1873, Willoughby Smith, an engineer from England, discovered the photoconductivity, or the capability to conduct electricity based on light intensity, of selenium while testing underwater telegraph cables. A decade later, Charles Fritts, an American inventor, made the first solar cells from selenium. He put a thin, wide layer of selenium onto a metal plate and covered it with a semitransparent gold-leaf film to create the first photoelectric module. Fritts generated a current and noted that it was a continuous current despite the intensity of light. At the time, Fritts predicted that the photoelectric plate may one day compete with coal-fired electrical generation.
The solar cell era begins
By 1953, scientists at Bell Laboratories were revisiting photovoltaic technology, this time using silicon to produce solar cells, further giving enough promise to the technology to support a focused research program. Scientists questioned how the weather impacted the solar cells and wanted to find a way to increase the amount of electricity produced. On April 25, 1954, Bell scientists presented a solar panel of cells that relied exclusively on light power, which they used to run a 21-inch Ferris wheel as a proof of concept. The New York Times wrote, “the silicon solar cell may mark the beginning of a new era, leading eventually to the realization of one of mankind’s most cherished dreams–the harnessing of the almost limitless energy of the sun for the uses of civilization.”
In the late 1950s, early efforts to help widely commercialize solar panels were unsuccessful. While the US Army and Air Force were interested in harnessing solar power as a primary source for a top-secret satellite project, the Navy was ultimately awarded the satellite project and chose to use chemical battery power instead of solar power as an energy source.
In the late 1950s, Dr. Hans Ziegler, a scientist and expert in satellite technology strongly encouraged the Navy to utilize solar cells that would last much longer than chemical batteries. Through much debate, the Navy finally heeded to Dr. Ziegler and as a compromise, allowed the placement of a dual power system consisting of chemical batteries and silicon solar cells on the project and just as Ziegler had suspected, the chemical batteries failed to work after a week and the silicon solar cells continued working for years.
Unfortunately, during the 1960s and 1970s, solar panel technology was often too expensive for mainstream consumer distribution. Nonetheless, as solar cell technology continued to evolve, the cost continued to decline. Dr. Elliot Berman is credited for contributing greatly to the affordability of solar panels in the mainstream market. He was able to help make solar panels more cost effective by using a lesser grade of silicon and packaging the cells with more cost-effective materials. This shift in solar panel production helped reduce the price of panels, which in turn enabled solar panel technology to compete in the wholesale power market for the first time.
America takes notice
In the 1970s President Ronald Reagan commended a pioneer from the Coast Guard, Lieutenant Commander Lloyd Lomer, due to his unwavering dedication to encouraging the transition of powering offshore buoys and other navigational aids from non-rechargeable batteries to solar cell technology. President Reagan honored Lomer for “saving a substantial amount of the taxpayer’s money through your initiative and managerial effectiveness as project manager for the conversion of aids to navigation from the battery to solar photovoltaic power.” Following Reagan, in 1978, President Jimmy Carter signed the Solar Photovoltaic Energy Research, Development, and Demonstration Act that authorized more research, development, and demonstration of solar panel technology in America.
Solar panel technology today
Since its inception, solar power technology has made constant progression. Advancements in photovoltaics (PV) and concentrated solar power (CSP) have produced a more effective hybrid technology for solar panel engineering, and have helped lower the cost significantly.
In 2016, MIT researchers were able to produce ultra-slim, flexible solar cells that are only 1.3 microns thick. These lightweight cells are said to weigh the same as soap bubbles, allowing future opportunities for use in certain technologies like cell phones. According to MIT, “conventional silicon-based solar modules produce about 6.8 watts per pound, but these new devices can generate more than 2,720 watts per pound, https://energy.gov/eere/videos/energy-101-solar-pv 400 times as much.” While this advancement is still in early phases, it could help widen the use of solar technology.
Continued scientific advancements have made vast improvements in solar panel technology, including increasing the capacity to harness more solar energy per unit of surface area. This is a vital factor in panel technology because the more energy a solar panel can absorb, the more efficient the panel becomes at harnessing solar energy. Today, solar panels can deliver at up to 22% efficiency. There have also been ongoing efforts to make solar energy even more affordable and efficient with an emerging technology called the “perovskite” solar cell. This crystalline material could ultimately replace silicon in solar panels and reduce costs using simpler production methods.
Today, most of the electricity generated in the U.S. comes from fossil fuels, like natural gas, coal, and petroleum. Renewable power accounts for just fewer than 15% of U.S. electricity generation, with solar accounting for .9%. As technologies evolve and are optimized, and solar power becomes more accessible and convenient through programs like community solar, there is hope that our production will shift and the solar energy share will grow. The infinite power of the sun is there, waiting for us to harness it.