From a New York rooftop in the 1800s to their first trip into space. From kidnapping and bribery to a world-changing mistake with an inkwell. Solar panels are one of humanity's greatest inventions, and their history is more fun than you might think.
Brief history of solar energy:
The first person to install a photovoltaic solar panel was Charles Fritts in 1884, when he mounted a pool table-sized array on a wooden frame on a New York City rooftop. Using selenium coated with a thin layer of gold, Fritts achieved less than 1% efficiency in converting sunlight into electricity, creating a current that he described as “continuous, constant, and of considerable strength.”
Fritts' project did not go very far; gold and selenium were not cheap or abundant enough to lead to commercially competitive products.
Fast forward 20 years and we get to Canadian ‘serial inventor’ George Cove, a multi-faceted scientist who filed numerous patents on propeller design, tidal energy harvesting, AC generators, electric clocks and watches. Building on Fritts’ work, Cove developed a ‘solar electric generator’ using a semiconductor material with a band gap extremely close to that of silicon, the primary material used in today’s mass-market solar panels, and a battery for energy storage and release.
Newspapers at the time reported that the generator cost about $20 to build (the equivalent of about $660 in today's money in 1909) and would power an early 1900s home for about ten years, eliminating the need for homeowners to connect to the rapidly developing electrical grid. Its 1909 demonstration in Halifax, Nova Scotia, attracted significant investor interest. By then, Cove had set up shop in New York and raised $5 million.
But according to Oxford researcher Dr. Sugandha Srivastav, her story took a strange turn when she claimed to have been kidnapped and offered $25,000 plus a house in exchange for quitting her job. It wasn’t an exaggerated claim at the time. “At the time, it was known that Thomas Edison (of Edison Electric) and J.D. Rockefeller (founder of Standard Oil) used various nefarious tactics to put their competitors out of business,” says Srivastav.
Cove claimed to have declined the offer and was subsequently released at the Bronx Zoo. But critics accused him of staging the incident as part of a scam or to generate media attention for his business. Whatever the case, Cove’s business quickly declined and never recovered — and the rise of coal and oil in 1911 soon eclipsed solar technology, effectively stalling solar innovation for the best part of 40 years.
“Obstructionism has been a major obstacle to the development and expansion of renewable energy in the past, and it continues to be so today,” Srivastav writes.
Explanation
While little happened around solar energy in the following decades, other important technologies were being developed that would later support its revival. In 1918, Jan Czochralski, a Polish chemist, accidentally discovered a method for growing single crystals (monocrystals) used in semiconductor chips, now known as the Czochralski method. This method remains the backbone of 90% of all electronics today.
The discovery came when Czochralski accidentally dipped his pen into a crucible of molten tin instead of an inkwell (a seemingly reasonable mistake), leading to a “eureka!” moment when he saw a solidified tin filament hanging from his pen, which he later confirmed was a single crystal structure.
The sun remained in the shadows, if you'll excuse the pun, until 1954, when scientists Gerald Pearson, Calvin Fuller, and Daryl Chapin at Bell Labs (Bell Telephone Company) developed the first practical silicon solar cell with a 6% conversion efficiency—much better than the sub-1% efficient cells of the previous century. Their breakthrough used the crystalline silicon process pioneered by Czochralski.
As an interesting side note, Bell Labs also invented the maser around that same time. In its day, Bell Labs was much like today's Google X Labs, a center of innovation and invention that changed the world.
The first major application of solar cells came in 1958 with the launch of the Vanguard I satellite, which became the first solar-powered object in space. Slightly smaller than a bowling ball, Vanguard I still orbits Earth today, but after a solid six-year run, it transmitted its final bytes of data in 1964. The solar cells on board were crucial because batteries alone could not keep it running for that long.
Although technological breakthroughs of this magnitude were rare from the 1960s to the 1980s, solar panel use gradually spread, especially in remote areas where power lines were impractical or too costly. For example, radio and television towers, weather stations, satellite ground stations, irrigation pumps, offshore oil platforms, lighthouses, and buoys began to rely on solar energy. And in developing countries, solar technology has brought electricity to remote villages, making essential services like lights and vaccine refrigeration possible.
Explanation
Multi-junction cells were developed in 1989. These cells stacked very thin layers of different materials to capture more energy from the sun, making them the most efficient panels to date. By 2006, researchers had achieved 46% efficiency with multi-junction cells, nearly twice as much as the best conventional crystalline silicon cells. However, these cells remain prohibitively expensive and are used mostly in specialized aerospace applications such as the International Space Station, which can generate up to an astonishing 120,000 kW with solar panels.
Perovskite—a material that has recently made headlines for its photovoltaic potential—has led to further efficiency improvements. With its unique crystal structure, perovskite has enabled tandem cells (combining layers of silicon and perovskite) to achieve efficiencies of over 30%.
Bifacial solar panels have also gained popularity in the last decade. Capable of capturing sunlight from both sides, these panels are primarily used in large solar power plants (designed to supply power to the grid) and are hung above reflective surfaces for maximum absorption. On a personal note, I have installed bifacial panels on both my home and my caravan due to their efficiency.
Today's solar panels are expected to last 25 to 30 years before their performance begins to degrade, yet they only lose about one percent of their generating capacity each year after their lifetime.
Portable and flexible solar technology is now bringing this cheap and reliable energy source to all kinds of new applications.
Explanation
One of the biggest breakthroughs in solar energy technology has occurred in the field of battery storage.
Because solar energy has the pesky limitation that it only produces power for part of the day, storing excess energy is crucial to making solar energy a reliable, 24/7 energy source—especially at the scale of municipal power grids.
As various different battery technologies have improved and costs have decreased, solar energy has become increasingly viable to provide consistent and reliable energy, even at night, using banks of batteries charged by the sun. Lithium-ion batteries have led the way, and newer technologies such as lithium-iron-phosphate (LiFePO4), iron-air, and more exotic forms of mechanical energy storage continue to improve in terms of energy density and cost-effectiveness.
It’s fascinating to watch these technologies evolve and find their place in the future clean energy mix. Some focus on short-term, high-speed power demand spikes, while others focus on long-term, slow-release grid reinforcements to keep grids stable as average daily solar generation dips in the winter and increases in the summer.
Despite its shaky beginnings in the 1900s, solar energy is now a giant and one of the most popular forms of energy as the world focuses on the race to zero carbon emissions by 2050. Utility-grade solar is currently the second cheapest form of electricity on the market, behind only onshore wind power – and in terms of Balanced Cost of Energy (LCoE), it’s around half the price of coal-fired power.
Since Charles Fritts’ first rooftop appliance, it has arguably become one of humanity’s most important innovations—a legitimately reliable, economically viable form of clean energy that can scale quickly enough to keep up with humanity’s ever-growing appetite for electricity. It’s a remarkable story, and one we’re seeing continue to unfold in real time.