History of solar energy: From ancient to modern

Solar panels seem like cutting-edge technology, but their story begins over 180 years ago with a curious French physicist and a jar of metal electrodes. Today's rooftop installations trace their lineage through brilliant inventors, accidental discoveries, and Cold War space races—transforming sunlight into the clean electricity that powers millions of homes.

The journey from laboratory curiosity to your neighbor's roof involved dozens of innovators across multiple centuries in more than one country. Here's the fascinating story of who really invented solar panels.

The photovoltaic effect: Where it all began

Picture this: It's 1839, and 19-year-old Edmond Becquerel is working in his father's laboratory in Paris. He places two metal electrodes into an acidic solution and notices something remarkable. When light hits the setup, it generates electricity.

Becquerel had no idea he'd just discovered the foundation of a multi-billion-dollar industry. He called it the "photovoltaic effect" – literally meaning "light-electricity." This young physicist had unlocked the secret that would eventually power satellites, calculators, and millions of homes.

This sounds simple now, but in 1839, it was revolutionary science.

Becquerel's original experiment used silver chloride electrodes in an acidic solution. The setup generated only tiny amounts of electricity, but it proved that light could directly create an electrical current without any moving parts. Initially dismissed by many scientists as a mere laboratory curiosity, the photovoltaic effect's practical potential wouldn't become apparent for generations.

Becquerel's discovery sat largely unused for decades. Scientists understood the principle, but the materials available in the 1800s were too inefficient and expensive for practical applications. It would take another 44 years before someone built the first solar cell that could generate meaningful electricity.

Early solar cell pioneers (1873-1890)

The next chapter in solar history required a different kind of scientist – one willing to experiment with unusual materials and push the boundaries of what seemed possible.

Willoughby Smith and the selenium breakthrough

In 1873, British engineer Willoughby Smith made an unexpected discovery while testing underwater telegraph cables: selenium's electrical conductivity increased dramatically when exposed to light.

Smith wasn't looking for solar applications. He was trying to solve a practical problem with telegraph systems. But his selenium discovery opened new possibilities for converting light into electricity.

In the late 1870s, William Grylls Adams and Richard Evans Day took Smith's work further. They proved that selenium could generate electricity directly from sunlight without any external heat source. This was the missing piece that made practical solar cells possible.

Charles Fritts: The first solar cell creator

In 1883, New York inventor Charles Fritts created the first practical working solar cell by coating selenium wafers with an extremely thin layer of gold—a device that could generate consistent electricity from sunlight.

Fritts' solar cell achieved only 1-2% efficiency, but it worked consistently, producing what he described as 'a current that is continuous, constant, and of considerable force'—marking the first device that could reliably convert sunlight directly into electricity.

The following year, Fritts installed these panels on a New York City rooftop—the world's first rooftop solar installation—proving that solar energy could power real devices beyond the laboratory.

Despite these early successes, selenium solar cells remained expensive curiosities. The efficiency was too low and the cost too high for widespread adoption. Solar energy needed better materials and manufacturing techniques.

The patent race begins (1888-1920)

The late 1800s sparked intense innovation in solar technology. Inventors across America and Europe raced to improve solar cell efficiency and find practical applications for this new technology.

Edward Weston's solar innovations

Edward Weston received two crucial solar patents in 1888 – U.S. Patent 389,124 and U.S. Patent 389,425. His approach differed from Fritts' selenium cells by using thermopiles (devices that convert heat into electricity).

Weston's designs used focused sunlight to heat thermopiles, which converted thermal energy into electrical current. His systems included tracking mechanisms to follow the sun and were designed for both electricity generation and mechanical power.

Other early inventors and their contributions

The solar patent race attracted inventors worldwide. In 1888, Russian scientist Aleksandr Stoletov created the first solar cell based purely on the photoelectric effect—converting light directly into electricity without the intermediate thermal conversion step.

American inventor Melvin Severy received patents in 1894 for solar thermal systems that could track the sun automatically. His "Apparatus for generating electricity by solar heat" included innovative mounting systems that kept solar collectors pointed toward the sun throughout the day.

These pioneers established fundamental principles still used in modern solar panels, proving that with the right materials and engineering, solar energy could become both practical and scalable.

Melvin Severy's 1894 patent included the first automatic sun-tracking system, allowing solar collectors to follow the sun's movement without human intervention. Modern solar installations still use similar tracking technology to maximize energy production.

The Bell Labs revolution: Modern solar is born

The 1950s brought the breakthrough that transformed solar energy from a scientific curiosity to a practical technology. Three scientists at Bell Laboratories created the first silicon solar cell, launching the modern solar industry.

The silicon breakthrough of 1954

Daryl Chapin, Calvin Fuller, and Gerald Pearson weren't trying to revolutionize renewable energy—they simply needed reliable power sources for remote telephone equipment in humid climates where batteries failed quickly.

The team knew that selenium solar cells were too inefficient for practical applications. They needed something better. Silicon, a semiconductor material, showed promise in early experiments.

After months of experimentation, they unveiled the first silicon photovoltaic cell on April 25, 1954. Achieving 6% efficiency—three times better than selenium cells—these silicon devices were also more durable and consistent than previous technologies.

The Bell Labs team demonstrated their silicon solar cell at a press conference, powering a small radio transmitter entirely with sunlight. The demonstration captivated audiences worldwide, with scientists eager to see what would come out of silicon's potential to revolutionize power generation in applications where conventional electricity was impractical or unavailable. The New York Times called it "the beginning of a new age" that would "free mankind from dependence on fossil fuels."

From laboratory to space program

Silicon solar cells found their first major application in space, where the harsh environment demanded reliable, lightweight power sources that could operate for years without maintenance.

In 1958, the Vanguard I became the first solar-powered satellite, launching with a tiny 1-watt solar panel to power its radio transmitters. Solar proved ideal for space missions because panels require no fuel, produce no emissions, and function reliably in vacuum conditions. This marked the first practical use of silicon solar cells and proved that photovoltaic technology could work in extreme conditions.

NASA's demanding requirements drove rapid improvements in efficiency and reliability that would eventually benefit terrestrial solar applications.

Space applications justified the high cost of early silicon solar cells. While terrestrial solar remained too expensive for most uses, satellites needed reliable power regardless of cost.

Solar goes mainstream (1970s-2000s)

The 1970s energy crisis transformed solar energy from an expensive novelty into a serious alternative to fossil fuels. Government support and rising oil prices created new opportunities for solar technology development.

The energy crisis catalyst

The 1973 oil embargo quadrupled gasoline prices and created widespread energy shortages. Americans waited in long lines at gas stations and faced heating oil shortages during the winter months.

This crisis sparked new interest in renewable energy sources. The federal government launched major research programs and offered tax incentives for solar installations. Solar energy suddenly seemed like a strategic necessity rather than an environmental luxury.

The University of Delaware built "Solar One" in 1973, the first building designed to run entirely on solar power. This hybrid system combined solar thermal heating with photovoltaic electricity generation, proving that solar energy could meet real-world building needs and showing how long such systems can reliably operate in practice.

Solar One combined solar thermal and photovoltaic (PV) systems in the first building-integrated photovoltaics (BIPV)* installation. The building, which was 70% solar-heated while generating its own electricity, operated successfully for decades and influenced modern net-zero energy designs.

*Unlike traditional solar panels mounted on top of existing structures, BIPV systems replace conventional building materials entirely. This approach eliminates separate roofing costs while generating electricity, making solar more economically attractive.

Efficiency improvements and cost reductions

The 1970s and 1980s brought steady improvements in solar cell efficiency and manufacturing techniques. Research laboratories and companies competed to create better, cheaper solar panels.

Between 1957 and 1960, Hoffman Electronics pushed silicon solar cell efficiency so that it reached from 8% to 14%, making solar power more practical for terrestrial applications beyond satellites.

*Multi-junction solar cells work by stacking multiple layers of different semiconductor materials, each optimized to capture a specific portion of the solar spectrum. This approach overcomes the efficiency limitations of single-junction cells, which can only capture a narrow range of wavelengths.

Government programs accelerated solar development throughout the 1980s and 1990s. The Solar Energy Research, Development, and Demonstration Act of 1974 committed federal resources to making solar "viable and affordable" for consumers.

Manufacturing improvements gradually reduced solar panel costs. Mass production methods developed for the semiconductor industry adapted well to solar cell manufacturing, driving down prices year after year.

Modern solar innovators and companies

Today's solar industry builds on 180+ years of innovation, but recent decades have brought revolutionary improvements in efficiency, aesthetics, and affordability.

Tesla and aesthetic improvements

While traditional solar panels worked well, their industrial appearance limited residential adoption. Tesla (after acquiring SolarCity in 2016) addressed this aesthetic challenge with solar roof tiles that integrate seamlessly with standard roofing materials.

Musk unveiled the solar roof featuring photovoltaic cells embedded in glass tiles designed to resemble conventional roofing materials—generating electricity while maintaining residential curb appeal.

Other companies have developed similar building-integrated photovoltaic (BIPV) solutions. Solar shingles, solar siding, and transparent solar windows offer new ways to integrate renewable energy generation into building design.

Current efficiency leaders and breakthrough technologies

Modern solar panels achieve efficiencies that early inventors could never have imagined. The best commercial silicon panels now exceed 22% efficiency, with laboratory cells reaching even higher performance levels.

Perovskite solar cells represent the next frontier in photovoltaic technology. These materials can be manufactured at room temperature using simple processes, potentially reducing costs while achieving high efficiencies.

Research laboratories have already created perovskite-silicon tandem cells exceeding 29% efficiency, suggesting that once manufacturing challenges are solved, solar energy could become even more affordable and widespread.

This record was set by scientists at the National Renewable Energy Laboratory (NREL) in Colorado in 2020. The breakthrough used a six-junction solar cell under concentrated illumination* equivalent to 143 suns. A variation of the same cell also achieved 39.2% efficiency under standard one-sun illumination.

*Concentrated illumination uses mirrors or lenses to focus sunlight onto small, highly efficient solar cells—similar to using a magnifying glass. The "143 suns" measurement means the light intensity was 143 times stronger than normal sunlight, allowing researchers to test maximum efficiency.

The Solar Boom of 2020-2024

The early 2020s marked solar energy's transition from alternative to mainstream. The Inflation Reduction Act of 2022 extended and enhanced federal tax credits, spurring record installation rates. In 2023 alone, the U.S. installed over 32 gigawatts of solar capacity—enough to power 6 million homes. Residential installations accelerated particularly rapidly, with rooftop solar becoming the fastest-growing home improvement category, outpacing pools, renovations, and additions.

Manufacturing has shifted dramatically toward bifacial panels that capture sunlight from both sides, increasing energy production by 10-30%. Tracking systems have become more affordable, with single-axis trackers now common in utility-scale installations. Meanwhile, residential solar-plus-storage systems have grown from niche products to standard offerings, with battery prices falling 80% since 2015.

China, the United States (often shortened to the U.S.), and India now account for two-thirds of global solar installations, but emerging markets in Southeast Asia and Africa are rapidly expanding in a more united global clean-energy push. Solar has become the cheapest electricity source in history in many regions, with utility-scale projects delivering power for under $0.02 per kilowatt-hour—cheaper than any fossil fuel alternative.

From invention to your rooftop: The transformation

The journey from Becquerel's 1839 laboratory experiment to today's rooftop installations represents one of the most dramatic cost reductions in technological history.

Modern homeowners benefit from all these historical innovations, enjoying solar panels more efficient, reliable, and affordable than early inventors could have imagined, especially after rooftop solar was popularized in residential markets worldwide.

A typical residential solar installation now costs $15,000-25,000 before incentives—a system that would have cost over $1 million in 1970s dollars. This dramatic price reduction has democratized solar energy, moving it from government programs and wealthy early adopters to mainstream households.

As of recent years, the solar industry employs over 250,000 Americans and installs enough capacity each year to power millions of homes. This growth continues the innovation tradition started by Becquerel, Fritts, and the Bell Labs team.

The future of solar technology

Solar innovation continues to accelerate beyond today's silicon panels, with researchers worldwide developing next-generation technologies that promise even greater efficiency and affordability.

Perovskite-silicon tandem cells layer different materials to capture more of the solar spectrum. These cells could achieve 35%+ efficiency while maintaining reasonable manufacturing costs.

Floating solar installations on reservoirs and lakes offer new deployment opportunities without using valuable land. These systems can generate power while reducing water evaporation and algae growth.

The inventors who created the first solar cells would be amazed by today's technology—from Becquerel's tiny laboratory current to gigawatt-scale solar farms. Their curiosity and persistence launched an industry that now provides clean, affordable energy to millions of people worldwide.

From Edmond Becquerel's 1839 discovery to your neighbor's rooftop installation, solar panels represent humanity's ingenuity in harnessing nature's most abundant energy source. With installation costs at historic lows and efficiency at historic highs, the story continues with each new installation and technological breakthrough—accelerating toward a future where solar provides the majority of the world's electricity.

Sergey Fedorov

Co-founder & CTO

Sergey has been running A1 SolarStore since 2017 with the main idea in mind – making going solar easier for everyone. Based on a thorough market research and his personal experience, he shares his ideas on both solar industry and management related topics

More articles from this author

Illustrator: Dasha Vasina