The first rooftop solar panels were installed in 1883

The first practical silicon solar cell was developed at Bell Labs

In 1953, scientists at Bell Labs attempted to develop a power source for phone systems in remote locations, as the dry battery cells lacked the necessary longevity. They experimented with solar power, but the selenium solar cells of the time were too inefficient, eventually leading to the usage of silicon.

Enough sunlight hits Earth in just 90 minutes to power the planet for an entire year

Despite this, in 2023, only 5.1% of electricity in the US came from solar energy. Solar panel technology has nonetheless made significant advancements since the 19th century, largely due to NASA's efforts in the space race.

The Ancient Chinese harnessed solar power for heating and cooling 6,000 years ago

Neolithic Chinese homes faced south for winter sun warmth, while overhangs shielded them from high summer sun. These efforts also influenced urban planning, with cities aligning streets east-west for optimal solar exposure.

The world's first geothermal power plant was built in 1913 in Devil's Valley

In Tuscany, Italy, Prince Piero Ginori-Conti of Trevignano established the plant nine years after creating a generator that powered five light bulbs using steam vents in the area. Within three years, a second plant was built with two generators, each with 10 times the energy output of the first.

Niagara power helped electrify early New York City

Tesla's AC system at Niagara Falls was so successful that electricity generated there lit up Broadway theaters and powered NYC's subway system in the early 1900s.

View an interactive chart of energy conversion efficiencies for various photovoltaics

This National Renewable Energy Laboratory visualization provides maximum confirmed efficiencies for nearly 30 research PV cell technologies from August 1975 to today. Concentrator multi-junction cells have led the field since 1993. (Desktop recommended site.)

Thomas Edison created the first strand of electric Christmas lights in 1880

Edison strung electric bulbs outside his laboratory in 1880, and his business partner Edward H. Johnson first wrapped a tree in lights in 1882. It wasn’t until the lights were commercialized in 1917 that they became common in household Christmas decorations.

Explore a gallery of electric vehicles from before 1920

In 1884, Thomas Parker invented the first practical electric car in London. By the turn of the century, early EVs were seen on the streets of Washington, DC. Automaker promotional materials included photographs of cars on mountain roads and other terrains.

See how New York City has grown since 1609

Wall Street and the southern tip of Manhattan were the first parts of the island to be developed beyond farmland by Dutch and English settlers. It wasn’t long until New York City resembled the city we know today.

The Rockefeller Center Christmas tree was first erected in 1931 by construction workers

The tradition of erecting a tree in Rockefeller Center officially began two years later, when the company continued what the Depression-impacted workers had started. Today, its lighting and nearby ice skating draw millions annually, making it one of America’s most famous holiday traditions.

Establishing the wind power grid required incentives, reliability, and affordability

Although wind was harnessed to generate electricity for individual buildings in the late 1800s, high costs, mechanical issues with turbines, and better fossil-fuel alternatives delayed wind power's widespread growth. After the oil crises of the 1970s, governments sought alternative energy sources and, in the decades that followed, provided tax credits to expand the wind power market.

The first glasshouse was constructed in 1931

The Maison de Verre in Paris was built to house a doctor's office on the ground level and an apartment upstairs. Unlike the typical model that would follow, this glass house exposed very little of the home's interior.

Solar panels can create pollinator-friendly habitats by protecting flowering plants

An example of agrivoltaics, where land is used for solar energy production and agriculture, the panels provide clean energy while also shading plants from excessive sunlight. Pollinator-friendly plants can improve water quality and reduce soil erosion by obstructing the wind.

The solar noon clock outside Rhodes Hall at Cornell is named after Bill Nye

In addition to displaying the analog time, the clock's face features an indicator disc that illuminates, even on cloudy days, whenever the sun reaches its highest point in the sky. Nye developed the initial apparatus designs, which were later co-engineered and built by Cornell staff and students.

Radioactivity was accidentally discovered when uranium left marks on photographic plates

In 1896, Henri Becquerel had been exploring phosphorescence—the emission of light of one color after an object is exposed to another color. He expected these emissions to come from objects exposed to sunlight, but he observed emissions after an overcast day.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

Read Norman Rosenthal’s original 1984 paper describing SAD

The study helped formalize research and diagnosis of seasonal affective disorder, catalyzing the development of therapies (like bright light) and leading to broader adoption of effective treatments. It also helped connect the influence of light and seasons on biological mechanisms in the human body, spurring exploration of circadian rhythms.

The first US ETF was launched in 1993

Exchange-traded funds are relatively new inventions, and they've grown significantly in popularity during their few decades of existence. They were first created as an alternative to mutual funds. A colorful visualization depicts the entire history of ETFs.

The story of the debut 1967 Consumer Electronics Show

Read an account of the origins of the first CES in New York in 1967, a story which is surprisingly difficult to find information about.

Credit reporting's earliest origins in the 1700s resemble a game of telephone, with rural merchants asking their most esteemed neighbors to vouch for them to sleuthing urban lenders

It would be decades before the system evolved into something more formulaic. For instance, New York City's Mercantile Agency—which was created to formalize information and rumors about borrowers, sorting the reports into enormous ledgers—wasn't started until 1841.

The first 3D printing patent was filed in 1967

Wyn Swainson, an English literature graduate student, filed a patent in Denmark for a system that scans an object and uses the scanning data to rebuild it using lasers that harden light-sensitive plastic. However, he never developed a working prototype. The idea originated from wanting to produce recreations of sculptures.

Rain-catching tubes provide new hydropower source for tropical regions

An experiment in Singapore showed that charge separation could be established by rainwater flowing through narrow tubes. The separation, which creates a voltage, could be scaled up in regions of high rainfall to provide a clean energy source.

The first college football game was played in 1869 between Rutgers and Princeton

On November 6, 1869, Rutgers defeated Princeton 6–4 in what is considered the first college football game. Played under soccer-like rules, it marked the birth of a sport that would evolve into American football.

Delmonico's was the first American fine-dining restaurant

The steakhouse opened in 1837 in Manhattan, creating what is now considered the first fine-dining restaurant in the United States, introducing gloved waiters, white tablecloths, and an à la carte menu. The establishment also claims it invented a few American staples, including eggs Benedict, which was supposedly named after two loyal customers.

The Google Doodle honoring Jan Ingenhousz, who discovered oxygenic photosynthesis

Born in 1730, the Dutch scientist expanded on existing knowledge that plants produce and absorb gases in his 1779 paper, which detailed that light was necessary for the biochemical processes that produce oxygen in plant leaves. He also identified that all parts of plants produce carbon dioxide at night.

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

While the first exchange-traded fund (a 'basket' of different assets that can be bought and sold on a stock exchange) in the US only launched in 1993, the global ETF market has grown to more than $10T in the short time since.

Learn more about the history of fireworks, which dates back to an accidental invention during an alchemist's quest for information about immortality.

Visualize the path of every solar eclipse from 1900 to 2099 and see what each looks like when observed from different locations on Earth.

Sears sold DIY house kits starting at $600 in its famous catalog from 1908 through the 1940s, resulting in roughly 10,000 'Sears and Roebuck houses' being built.

Sony set the standard for cylinder-shaped batteries when it repurposed manufacturing equipment used to make rolls of magnetic recording tape.

The 19th-century painters of the Hudson River School were among the first American romantics, with portraits that displayed the natural beauty of the young country.

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Graffiti dates back to at least ancient Pompeii, where citizens scrawled messages to one another on public walls

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

The first horror movie is believed to be George Méliès' 1986 short 'The Haunted Castle,' which pioneered the use of special effects

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

Poison ivy was sent to Europe in the 1600s as an exotic, ornamental oddity, where it was purposefully grown in the English royal gardens at Kew, the Faculty of Medicine in Paris, and a few other locations.

Long before Major League Baseball began allowing instant replay for balls and strikes, an umpire reluctantly used the technology to determine whether a hit was a home run, a move that inadvertently ushered in a new era for the sport.

Trace how the Bill of Rights, inspired by centuries of political theory, took shape between 1774 and 1789.

In 1963, a basement renovation in Turkey revealed a passageway to a hidden, multilevel underground city that once housed as many as 20,000 people

Planeterrellas create artificial auroras that mimic the atmospheric displays of light by setting up an electric field between two metal balls in a jar filled with a small amount of air.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

English mathematician Ada Lovelace wrote the first computer algorithm a century before computers existed and hypothesized that computing devices would one day be able to compose music—foreseeing the generative AI systems of today.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

The word 'jazz' evolved from 'jasm,' 19th-century American slang for 'energy'

Artificial coral reefs have been 3D printed from nontoxic, biodegradable terracotta clay, which coral polyps have used as a foundation for rebuilding marine ecosystems.

70 years ago today, city officials in Santa Cruz, California, banned rock 'n' roll to protect its youth from corruption after witnessing a 'provocative' concert the night before.

Abraham Lincoln was almost assassinated weeks before his inauguration as he traveled from Illinois to DC through Baltimore in 1861; it took two independent claims for Lincoln to be convinced the threat was real