The journey of photovoltaic technology is a fascinating chronicle of scientific breakthroughs and technological advancements. With solar panels becoming more prevalent in regions like the Philippines, it’s essential to understand the historical progression that has led to the widespread adoption of this renewable energy source. From its inception nearly 170 years ago, photovoltaic technology has continually evolved, paving the way for a sustainable future.
The Dawn of Photovoltaic Discovery
In 1839, the seeds of photovoltaic technology were sown by Edmond Becquerel, a young French experimental physicist. At the tender age of nineteen, Becquerel discovered the photovoltaic effect while experimenting with an electrolytic cell composed of two metal electrodes. This marked the beginning of a journey that would revolutionize energy production.
The late 19th century saw further advancements. In 1873, Willoughby Smith discovered selenium’s photoconductivity properties. Building on this, William Grylls Adams and Richard Evans Day, in 1876, demonstrated that electrical current could be initiated in selenium through exposure to light. This discovery set the stage for Charles Fritts, an American inventor, who in 1883 described the first solar cells made from selenium wafers.
Early 20th Century Breakthroughs
The early 20th century brought significant theoretical and practical advancements. In 1905, Albert Einstein published a groundbreaking paper on the photoelectric effect, laying the theoretical foundation for photovoltaic technology. Robert Millikan, in 1916, provided experimental proof of Einstein’s theory.
In 1918, Jan Czochralski, a Polish scientist, developed a method to grow single-crystal silicon, known as the Czochralski process, which would later become crucial for silicon-based solar cells.
The Rise of Commercial Solar Power
The commercial era of solar power began in earnest in 1954 when Bell Laboratories discovered the photoelectric properties of silicon, leading to the development of the first high-power silicon photovoltaic (PV) cell. This innovation prompted the New York Times to predict a future source of “limitless energy of the sun.”
By 1955, Western Electric began selling commercial licenses for silicon PV technologies, leading to the success of products like PV-powered dollar bill changers. The technology’s potential was further demonstrated in 1958 when a PV array powered radios on the US Vanguard I space satellite.
Global Expansion and Technological Advancements
The 1960s and 1970s were marked by global expansion and efforts to reduce costs. In 1963, Sharp Corporation produced a viable photovoltaic module of silicon solar cells, installing a 242-watt PV array on a lighthouse in Japan, the largest of its time. NASA’s launch of the Orbiting Astronomical Observatory with a 1-kilowatt PV array in 1966 showcased the technology’s potential in space exploration.
Efforts to reduce costs began in the 1970s, with research eventually slashing PV costs by 80% for applications like offshore navigation warning lights and remote power needs. The establishment of Solarex Corp by ex-NASA scientists in 1973 and Japan’s “Project Sunshine” in 1974 further fueled innovation and development.
Modern Era: A Surge in Adoption
The 1980s and 1990s saw PV technology becoming more efficient and widespread, powering consumer electronic devices and benefiting from government subsidy programs. Germany’s “100,000 Solar Roofs” initiative in 1990 and Japan’s “70,000 Solar Roofs” program in 1994 spurred market growth and reduced reliance on subsidies.
Since 2000, the solar-cell industry has experienced dramatic growth. Once considered a luxury, solar power is now a practical solution for remote areas worldwide. Its environmental benefits have led commercial hubs to replace polluting diesel generators with cleaner, efficient solar cells.
As Science magazine aptly put it, solar cells represent a “dream solar technology,” combining sophistication with environmental friendliness. The evolution of photovoltaic technology underscores a remarkable journey from scientific curiosity to a cornerstone of sustainable energy.