The Sun and our Earth
Solar energy is finding a well-established role in today’s clean energy economy. But despite what you may have been taught to believe, solar technology isn’t a new thing. There is in fact a long history behind photovoltaics (PV) that brought the concept of solar energy to completion. Let’s go back in time to discover the origins of solar PV and explore the history of solar energy.
If you took science in school, you might be aware that the sun is a crucial factor to life on Earth. Humans, animals, and plants all use the sun’s energy in one form or another.
The Power of Plants
Plants use a process called photosynthesis to make food. They do this by trapping the sun’s light with their leaves and changing water and carbon dioxide into a sugar called glucose. Glucose is used by plants for energy and to make other substances like cellulose and starch. Plants require photosynthesis in order to grow, bloom and produce seed. Without adequate sunlight, glucose cannot be manufactured, energy reserves are depleted and plants die.
All nutritional energy comes from the sun. Plants use chlorophyll to photosynthesize the sun’s energy into plant energy. Animals will either feed on plants for that energy, or feed on the animals that have eaten that plant energy. The food chain begins with the sun and then the energy flows to producers.
First Known Uses of the Sun
Along with harvesting the sun’s energy through food, historians suggest that humans were using solar energy as early as 7th century B.C. to light fires through magnifying glass. This was followed by the Greeks and Romans in 3rd century B.C who were known to use mirrors to light torches with the sun, which was also documented in Chinese civilization later in 20 A.D.
Early civilizations also incorporated the sun’s energy into architectural structures, which are still popular today. The use of sunrooms, were found in some of the most iconic Roman bathhouses. These are spaces with massive windows to admit a large amount of sunlight. In the 1200s A.D., the Anasazi Native Americans situated sunrooms in south-facing structures on cliffs to capture the warmth of the sun during the cold winter months.
In 1767, researchers and scientists harnessed sunlight to power solar ovens, devices that heated both food and beverages. It is clear the concept of manipulating the power of the sun was a common practice even thousands of years before the era of solar panels.
When did Humans Invent Solar Panels?
While there is some debate around when solar panels were created and who should be credited for them, most historians point to French scientist Edmond Becquerel. He determined that light could increase electricity generation when two metal electrodes were placed into a conducting solution. This breakthrough was defined as the “photovoltaic effect”, which was influential in later PV developments with the element selenium (atomic number 34 on the periodic table).
In 1873, an English electrical engineer named Willoughby Smith discovered the photoconductivity of the element Selenium. William Grylls Adams, professor of Natural Philosophy at King’s College in London, along with his student Richard Evans Day, both demonstrated in 1867 that selenium could be used to transform solar energy directly into electricity. A few years later in 1883, American Inventor Charles Fritts produced the first photovoltaic cell using selenium wafers. This is the reason that some historians credit Fritts with the invention of solar cells.
Solar cells as we know today are made with silicon (atomic number 14 on the periodic table), not selenium. Therefore, some consider the true invention of solar planes to be tied to Daryl Chapin, Calvin Fuller and Gerald Person. Together they created the first silicon PV cell at Bell Labs in 1954. This invention was the first instance of solar technology that could power a device for several hours of a day. The first ever silicon solar cell converted sunlight at 4% efficiency. This is less than a quarter of what modern cells are capable of.
Other Significant Events in the History of Solar Energy
- Solar Panels in Outer Space
As the space age progressed, solar panels were employed to power various spacecraft, such as satellites. In 1958, The Vanguard I satellite used a one-watt panel to power its radios. Vanguard II, Explorer II and Sputnik-3 all used solar technology in that same year. In 1964, NASA was responsible for launching the first Nimbus spacecraft, a satellite that ran entirely on a 470-watt solar array. NASA then launched the world’s first Orbiting Astronomical Observatory in 1966 that was powered by a one-kilowatt array.
- Oil Shortages in the 1970’s
During a period of high inflation, the United States’ reliance on foreign energy resources was highlighted. They needed alternative energy sources because they were running out of necessities. President Jimmy Carder had solar panels placed on the White House roof at the time. This was an act to raise awareness about clean energy and made a statement about the accessibility of solar energy to the public. President Ronald Reagan later authorized the removal of these panels. But during his first term, President Barack Obama later requested they were reinstalled along with a solar water heater.
- The First Solar Residence
“Solar One“, was built at the University of Delaware in 1973. This system ran on a hybrid supply of solar thermal and solar PV power. It was also the first instance of building integrated photovoltaics (BIPV). The array didn’t use solar panels, instead it had solar integrated into the rooftop. This is similar to the design of Tesla’s roof product.
- Achievements in Solar Conversion Efficiency
Between 1957 and 1960, Hoffman Electronics were responsible for several innovations in PV energy which increased conversion rates from 4% to 14%. In 1985, the University of South Wales improved this to 80% efficiency. Then the National Renewable Energy Laboratory and Spectro Lab Inc. partnered in 1999 to develop a solar cell with a 33.3% efficacy rate. This record was broken in 2016 by The University of South Wales when researchers reached 34.5% efficacy.
- Solar-powered Airplanes
Solar Challenger was built by Paul MacCready in 1981. It was the first aircraft to run on solar power, and was the first flown across the English Channel from France to the U.K. In 1998, the “Pathfinder“, a remote-controlled solar airplane set an altitude record after reaching 80,000 feet. That record was broken by NASA in 2001 when they reached 96,000 feet with their non-rocket aircraft. Betrand Piccard completed the first zero-emissions flight around the world in 2016 with “Solar Impulse 2”, the world’s largest and most powerful solar-powered airplane.
The Cost of Solar Over Time
Prices for solar PV modules have dropped substantially over the past few decades. This has lead to a surge in consumer demand producing 2,399 MW of solar energy as of Dec 31, 2021, 87% more than the previous year. In 1956, solar panels cost roughly $300 per watt. By 1975, that figure had dropped to just over $100 per watt. Today, a solar panel can cost as little as $2.50 a watt in Alberta. Consider this: since 1980, solar panel prices have dropped by at least 10% every single year. The plummeting cost of solar is largely responsible for the growing popularity of solar and the legitimacy of PV as a reliable energy source in today’s world.
Present Day Solar Power
Solar technology has come a long way from their beginnings, and it has a long list of meanings in today’s day and age. It spans through countless industries and contributes power to hundreds of different technologies and gadgets. If you are ready to start your personal solar journey, get a free estimate with Gridworks Energy and learn just how much solar can save you!