In theory, solar energy was used by humans as early as the 7th century B.C. when history tells us that humans used sunlight to light fires with magnifying glass materials. Later, in the 3rd century B.C., the Greeks and Romans harnessed solar power with mirrors to light torches for religious ceremonies.
In 20 A.D., the Chinese recorded the same use of mirrors. The concept of sunrooms in buildings was also popular. Some of the most famous Roman bathhouses were sunrooms located on south-facing buildings.
Later in the 1200s A.D., ancestors of the Pueblo Native Americans known as the Anasazi situated themselves in south-facing abodes on cliffs to capture the sun’s warmth during the cold winter months. Researchers and scientists used sunlight in long-distance power ovens in the late 1800s. They also developed solar-powered steamboats.
Ultimately, it’s clear that even thousands of years before the era of solar panels, the concept of manipulating the sun’s power was a common practice. The development of solar panel technology was an iterative process involving many scientists. Naturally, there is some debate over when they were invented and who should be credited.
Some people credit the invention of the solar cell to French scientist Edmond Becquerel. He determined light could increase electricity generation when two metal electrodes were placed in a conducting solution. The photovoltaic effect influenced later selenium PV developments.
In 1873, Willoughby Smith discovered that selenium had photoconductive potential, leading to William Grylls Adams’ and Richard Evans Day’s 1876 discovery that selenium creates electricity when exposed to sunlight. A few years later, in 1883, Charles Fritts produced the first solar cells made from selenium wafers, which is why some historians credit Fritts with the actual invention of solar cells.
However, as we know them today, solar cells are made with silicon, not selenium. Therefore, some consider the true invention of solar panels to be tied to Daryl Chapin, Calvin Fuller, and Gerald Pearson’s creation of the silicon photovoltaic (PV) cell at Bell Labs in 1954.