When we think of solar power today, we often think of renewable energy in general. Or maybe we think of sustainable living. Or perhaps we even think of the Federal Solar Tax Credit. But how did we get to where we are today with solar technology? What took place? What challenges had to be faced, and overcome? Let’s look back at the history of solar panels and see just where it all came from.

1839 – 1883

The true history of solar panels began in 1839, with a young French scientist named Alexandre-Edmond Becquerel. Young Becuqerel had been inspired by his father, who was also a scientist, to study luminosity and electricity. One day Bequerel was experimenting in his father’s laboratory when he unintentionally discovered something incredible. He created what would later be referred to as the world’s first photovoltaic cell. First, he took platinum electrodes (electrical conductors), and coated them with silver bromide. He then illuminated them by holding them in the sunlight. An electrical voltage and current was generated. Thus pure, solar energy was born, and study of the photovoltaic effect, then called the Bequerel Effect, began. Today the Becquerel Prize, named in his honor, is awarded each year for “outstanding merit in photovoltaics” at the European Photovoltaic Solar Energy Conference and Exhibition. Bequerel would continue to further his scientific career in the study of light and electricity. However, the next chapter in the history of solar panels took place years later in the 1860’s in England.

Willoughby Smith, an English electrical engineer, discovered that selenium bars could also be affected by sunlight. He first became interested in the late 1860’s, when he was used selenium bars to detect flaws in cables. He noticed that at night, the selenium bars worked perfectly well, but performed poorly in the daytime. Smith suspected that the effectiveness of the bars had to do with the amount of light that fell on them, and began to conduct a series of experiments. Smith discovered that selenium reacted to the intensity of the light. The results of these experiments were released in 1873. The findings went on to inspire two other English scientists- Professor William Grylls Adams, and his student Richard Evans Day. They confirmed that selenium reacted when exposed to light, and that sunlight generated electricity within the solid material itself. They called the current of electricity produced by the light the photoelectric effect.

Charles Fritts SolarOnce more, the discoveries of sunlight generating electricity caught the interest of a scientist. This time, it was Charles Fritts of New York, U.S.A. who took the next step forward. It could be said that, in a way, the history of solar panels truly begins with him. This is because Fritts was the one who created the photoelectric module- the very first solar panel. In 1883, he took a metal sheet, and spread a thin layer of selenium onto it. He then covered that with a very thin, semi-transparent film of gold-leaf.

The results? Fritts reported that his creation produced an electric current “that is continuous, constant, and of considerable force[,]… not only by exposure to sunlight, but also to dim, diffused daylight, and even to lamplight.” Fritts was so excited about this creation and the results that he said “we may ere long see the photoelectric plate competing with [coal-fired electrical-generating plants].” At that time, the first fossil-fueled plants had just been built by Thomas Edison. In fact, coal power was only 3 years older than the Fritts solar panel.

Unfortunately, it seemed that the stars were aligned against this early discovery. While some scientists saw this new invention as a source for limitless energy, others were more skeptical. The materials needed to create the solar panels were expensive, and the amount of energy they produced could not offset the cost. Furthermore, the conversion from sunlight to electricity was not well understood, and few scientists chose to pursue further study into photoelectrics. Solar energy seemed once again to be nothing more than a distant dream.

1905 – 1954

That is, until 1905. That year Albert Einstein revolutionized the way light was viewed with a paper on the photoelectric effect. In this paper, he showed that light carries energy, and the shorter the wavelength of light, the more energy it carries. This was able to explain why selenium was so reactive to light, and how the electricity was created. With the science behind it now explained, this phenomenon was given the term we still use today- the photovoltaic effect. With this added legitimacy, people’s interest in the history of solar panels, and the study of them, were renewed.

Dr. Bruno Lange, a German scientist, also invented his own version of the solar panel in 1931. He believed that, “in the not distant future, huge plants will employ thousands of these plates to transform sunlight into electric power… that can compete with hydroelectric and steam-driven generators in running factories and lighting homes.” Unfortunately, the optimism expressed by Dr. Lange turned out to be unrealistic. While the science behind them had been proven, solar panels could only convert sunlight to electricity at 1% of the capture rate. This low conversion efficiency could not compete with the growing fossil fuel industry, which was a more powerful and reliable energy source. As one scientist bluntly stated, “The photovoltaic cells will not prove interesting to the practical engineer until the efficiency has increased at least fifty times.”

Silicon Cell Research Calvin Fuller Gerald PearsonAnd then came the beginning of what would be called the Silicon Revolution. In 1954, there two scientists working for Bell Laboratories named Calvin Fuller and Gerald Pearson. These men invented two things that would change the face of technology forever. Those things were the silicon transmitter, which is used in most electronics today, and the first silicon solar cell. Originally the research had been performed on selenium, as the previous studies had been. However, after discovering how easily silicon transmitted electricity, they decided to create the cell using silicon. They immediately experienced greater energy production in their experiments. With this powerful discovery, they would then go on to produce the very first silicon solar panel.

1970’s – 2019

Dr Elliot Berman SolarDespite ongoing development and research into solar technology throughout the 1950’s and 70’s, the cost of solar panels was still very expensive. To commercialize solar, the cost of the materials and the process of creating the solar panels would have to be decreased. In the early 1970’s, Dr. Elliot Berman did just that by reducing the cost per watt from $100 to $20. This made it economical enough to use it to power satellites and space crafts. It was also used to power offshore navigation warning lights, railroad crossings, and remote areas where utility-grid connections were too costly to implement. In 1977, seeing the potential of a renewable, limitless energy source, the U.S. Department of Energy created the U.S. Solar Energy Research Institute. It would eventually come to be known as the National Renewable Energy Laboratories.

Meanwhile, occurrences overseas were helping to drive down prices of solar panels worldwide. In 1991, Germany launched a program to cover 1,000 roofs with solar panels. In 1999, that program was expanded to 100,000. Meanwhile in Japan, a subsidy program called “70,000 Solar Roofs” was begun. These large programs, as well as numerous small ones worldwide, drove up interest in solar panels while simultaneously driving down costs. Between the 1970’s and the 2000’s the cost per watt of solar panels decreased from $5 to just $1. And between 2000 to now, the price has gone down ever further than that.

Between these market forces and technological advances, solar panels today have become efficient and affordable. And while the cost of solar panels has been steadily decreasing, the cost of electricity from traditional, dirty sources such as coal and oil has been steadily increasing. People are quickly coming to realize that solar panels are not only cost-effective, but are also a safeguard by providing a reliable way to power their home. Now homeowners, business owners, and even utility companies are starting to switch to renewable energy, because the savings produced by doing so make it a simple choice.

Even state and city governments are joining in. Hawaii, California, New Mexico, Puerto Rico, and Washington D.C. have all pledged to go 100% renewable in the coming years. Many cities are now joining in as well, such as Cincinnati, Chicago, Atlanta, Denver, Orlando, and many others.

ADT Solar has helped thousands of customers switch from traditional, fossil-fueled electricity to clean, green energy to power their homes and businesses. Within the last decade alone, solar has grown worldwide, and green energy is spreading from corner to corner. We are proud to play our part in shaping the future of energy as we knowing. Years from now, we will be able to say that we made our mark in history by helping people to use the power of the sun to brighten their lives, and homes.

For more information on how you can utilize clean energy, contact ADT Solar today. Our Solar Energy Specialists will be happy to speak with you, and schedule a free consultation to help you start saving.