How Was Solar Energy Discovered?

The discovery of solar energy was not really the result of a singular event, but is rather more of a concept that evolved over many years of human history. The human use of solar energy has gone from simply noticing that the sun has its own energy and heat, to learning how to capture that energy efficiently for our own purposes, to the development of the ever-efficient technologies of today that have the potential to power our homes, economies, and human development all around the world for a more sustainable future.

The history of solar energy

700 B.C.  Humans first learn to make fire through the concentration of sunlight using a magnifying glass [1].

214-212 B.C.  A legend recounts how the Greek inventor Archimedes used a “heat ray” to set enemy ships on fire by reflecting and redirecting the sun’s light with a series of mirrors [2].

1767  The first solar oven was invented by Swiss scientist Horace-Benedict de Saussure.  The oven was created with an insulated box that was covered with three glass layers that were used to concentrate solar heat. This solar oven reached an internal temperature of 230 degrees fahrenheit [3].

1800s  Augustin Mouchot performed many experiments in the field of solar thermal energy [4].

1839  19-year-old French scientist Edmond Becquerel discovered the photovoltaic effect after finding that certain materials would undergo a change in their electric voltage when they were exposed to light [5].

1873 English Engineer Willoughby Smith discovered that selenium has a high photoconductivity, as well as a capacity to produce solar energy. This discovery proved that solid materials could convert light into electricity without requiring heat or moving parts [6].

1876  Professor William Grylls Adams and his student, Richard Evans Day, observed an electrical current after placing two electrodes onto a plate of selenium that had been exposed to light [7].

1883  American inventor Charles Fritts invented the first photovoltaic solar cells using selenium wafers [8].

1887 Heinrich Hertz discovered the capacity of ultraviolet rays to cause a spark of electricity to jump between two electrodes [9].

1891 The first solar heater was created [10].

1905  Albert Einstein published a paper on how the photoelectric effect works [11].

1908  William J. Baileys invented a copper collector using copper coils and insulated boxes [12].

1916  Scientist Robert Millikan experimentally demonstrated the photoelectric effect [13].

1918  Polish scientist Jan Czochralski discovered how to grow single-crystal silicon, laying the foundation for modern silica-based solar cells [14].

1947  Solar powered equipment became popular in the U.S. following World War II [15].

1953-1955  Calvin Fuller, Gerald Pearson, and Daryl Chapin created the first silicon photovoltaic solar cell capable of producing enough electricity to power small electrical devices [16].

1956  Solar cells became available commercially, but are far too costly for most people’s use at $300 for each 1 watt solar cell. Solar cells began to be used in toys and radios, making them the first consumer solar-based products available on the market [7].

1958 Solar power is first used in satellites and space stations. In the late 1960s, solar power was considered to be a standard issue for powering satellites [17].

1970s  Solar cell manufacturing became more efficient, reducing the price from $100 per watt to $20 per watt [18].

1977  The U.S. federal government launched the Solar Energy Research Institute, followed by other national governments around the world [19].

1970s-1990s  Solar power became more widely available and began to be used in a wide variety of applications, from railroad crossings, remote homes, telecommunication towers, irrigation, solar powered cars, solar powered aircraft, and large-scale solar power energy plants.

1999  Photovoltaic solar cell technology became more efficient, with an efficiency of 36 percent [20].

2012  An increase in large-scale solar power plants were built around the world, including the construction of the Golmud Solar Park in China that has an installed capacity of 200 megawatts and India’s Gujarat Solar Park that has a combined installed capacity of 605 megawatts [21].

Today, solar cells are increasingly being applied to more uses in more places around the world. As solar technology quickly evolves to become one of the most cost-effective and efficient sources of energy that humanity has ever had, we will likely see solar power become increasingly common throughout our lives and in our local communities. Such developments are a very welcome sight as humanity necessarily works toward a low-carbon future.