Humans have used geothermal resources for thousands of years

Geothermal power can be used beyond heating and energy production

Depending on the depth of the natural vents or artificial wells drilled, the surrounding fluid temperature will vary greatly—from 10 to 371 degrees Celsius (50 to 700 degrees Fahrenheit)—allowing for various applications, including the drying of cement, concrete, and lumber, as well as the processing of pulp and paper.

Geothermal power can generate electricity and provide direct heating for homes

By drilling several kilometers through penetrable rock, wells can access highly pressurized groundwater warmed by thermal energy trapped beneath Earth's surface. This water can be turned into steam to create electricity in generators. Heating systems several meters deep can pump fluid underground before circulating it through buildings.

Wastewater from geothermal power plants helps melt sidewalk snow in Iceland

Located on the Mid-Atlantic ridge, where the North American and Eurasian tectonic plates move apart, the nation saw geothermal power meet more than 90% of its heating demand in 2024. After the hot water produced by these plants is used to heat homes and businesses, it is transferred through small pipes beneath Reykjavík's sidewalks.

Like nuclear power, US geothermal power plant construction stalled for decades

Development and investment into geothermal energy took off in the 1960s. However, by the 1980s, companies repeatedly failed to find reservoirs of hot water when exploring new locations, and investors lost interest in the expensive drilling required. By the 2020s, technological advancements had finally helped mitigate exploration risk and expand viable drilling locations.

The continuous decay of radioactive elements regenerates geothermal energy reserves

Geothermal power is a renewable energy source derived from Earth's interior, where the core reaches temperatures exceeding 5,000 degrees Celsius (9,000 degrees Fahrenheit). These temperatures result from leftover energy from collisions during planetary formation, with radioactive decay in the core releasing additional energy that travels to the surface.

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.

Geothermal power plants can provide large-scale energy storage for other systems

These facilities can store excess energy from solar and wind power as hot water or steam, which can be used to run turbines to generate electricity when other renewable energy sources are unavailable. Simulations have found efficiencies of 90% during a storage-use cycle, making it comparable to lithium-ion batteries.

A look at hydrothermal vents, where barophiles and hyperthermophiles survive boiling water

Discovered in 1977 during an exploration of the Galapagos Rift, these seafloor openings spew hot magma and chemicals that heat seawater to hundreds of degrees. Without the sunlight found at depths of less than 1,000 meters (3,281 feet), extremophiles in these environments convert released chemicals into energy to survive, alongside surviving extreme pressures.

Fracking technology can help make geothermal power possible almost everywhere

Generating electricity from Earth's thermal energy has previously required existing underground reservoirs of hot water and permeable rocks through which the fluid naturally escapes. Today, fractures can be artificially created to form fluid pathways, and surface water can be injected underground and brought back to the surface.

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.

Explore next-generation geothermal projects worldwide

This tool from the Clean Air Task Force allows users to see the location of geothermal power systems to depths of 12.5 kilometers (7.8 miles), where temperatures reach about 450 degrees Celsius (842 degrees Fahrenheit), including proposed, abandoned, and in-development projects.

Native Americans developed pottery and religion, and experienced population growth during the Woodland period

Between 500 B.C.E. and 1100 C.E., Indigenous peoples produced pottery and practiced animism, a spiritual worldview in which animals, plants, and natural forces are believed to possess sacred power. They moved seasonally to make the most of available resources.

The ancient Greeks and Romans were known to take vacations.

Ancient Romans took trips to the coast to beat the heat and relax.

Geothermal power may meet 15% of global electricity demand growth through 2050

According to the International Energy Agency, the estimate would require the construction of geothermal capacity with an annual output equivalent to the combined electricity consumption in the US and India in 2024. The report suggests geothermal investment will reach $2.5T by 2050, with the integration of fracking technologies decreasing costs by 80% by 2035.

Aquifer thermal energy storage systems bank water heated during the summer in aquifers—layers of porous rock, gravel, and sand filled with groundwater—which are then collected in winter to warm homes.

Medieval European winters were colder than ours, but peasants stayed warm

Medieval winters were colder than ours today while the continent was mired in the so-called Little Ice Age. Without modern technologies, peasants survived with simple, sometimes genius, solutions, including central, chimney-less fireplaces (vented by small, draftless vents) and decorative handwarmers.

Geothermal power can reduce the dangerous mining of rare earth elements

Geothermal brines—mineral-rich underground fluids extracted for use in geothermal plants—contain small concentrations of REEs that can be recovered after energy generation. Although researchers suggest that this retrieval requires complex extraction methods at a significant scale to account for high flow rates, the chemical processes also occur in traditional REE processing.

Humans were forced to adapt to survive a supervolcano eruption 74,000 years ago

The Toba supereruption ejected 2800 cubic kilometers of ash, resulting in global cooling from blocked sunlight and acid rain. Archaeological sites show that humans developed bow-and-arrow technology to survive in arid conditions by fishing in seasonal waterholes.

The warmest waters in the ocean are found at hydrothermal vents—hot springs on the seafloor that discharge plumes of mineral-rich water.

As of 2022, just 0.5% of installed renewable energy capacity worldwide is geothermal

Despite being able to generate electricity regardless of the weather, solar (28%) and wind (27%) are far more prevalent, primarily because of their lower upfront costs. Geothermal plants use 88% less space than solar farms to produce the same energy, but have been restricted to geologically active regions.

The scientific name for northern lights came from two Greco-Roman gods

Although cave paintings may have depicted them millennia earlier, one of the oldest known references to auroras is a Babylonian cuneiform tablet from about 600 BCE. In 1619, Galileo Galilei named the phenomenon in the northern hemisphere "aurora borealis" after the Roman goddess of dawn—Aurora—and the Greek god of the north wind—Boreas.

Geothermal heat pumps have the greatest upfront cost of any home heating system

As of 2025, installations of these systems can range from $15,000 to over $40,000, significantly more than for furnace-air conditioner and air-source heat pump systems. However, they are up to 50% more efficient than these alternative systems, making them able to pay for themselves within 15 years.

In 2009, accidentally drilling into magma provided time capsules of volcanic glass

While drilling for geothermal energy in Iceland's Krafla Geothermal Field, magma encountered at a depth of 2,100 meters quickly formed glass upon making contact with drilling fluid. By trapping dissolved gases, volatile chemicals, and the physical characteristics of magma before cooling, the glass acts as a time capsule of ancient volcanic activity and magmatic conditions.

When humans discovered fire

Fire has proven crucial for the development of human civilization, but there was a time when our hominin ancestors could not make effective use of it. This article traces the major milestones in humanity's journey with fire based on evidence from...

The ancient uses of asphalt

Asphalt is derived from bitumen, a naturally occurring byproduct of decomposed organic materials. As one of the thickest forms of petroleum, the substance has been in use by humans and their ancestors for at least 40,000 years for various purposes, including as a sealant, an adhesive, decoration, and more. Learn more about this ancient material here.

Why did this prehistoric culture regularly burn their homes?

This article explores why the Cucuteni-Trypillia culture may have regularly burned their homes. The Cucuteni-Trypillia culture is the oldest known in Europe, dating back to about 5,500 BCE in present-day Romania, Russia, and Ukraine. The...

Ancient ghost stories appeared in texts like 'The Odyssey'

Sharing ghost tales has been around for centuries. Ancient Mesopotamia, Rome, and Greece each had their own chilling stories about encountering spirits. Find mentions of specters in some of history’s most famous writings like the "Epic of Gilgamesh" and "The Odyssey."

Cold-blooded reptiles seek heat, and that behavior may help combat fungal infections

This Radiolab podcast episode takes on the idea that though our human bodies are too warm for the majority of fungal species to effectively replicate inside our bodies, that's not the case for reptiles. Yet when those species warm their bodies by basking in the sun on rocks, they can soak up heat and may also help keep fungal infections in check.

Bottled water started as a 19th-century wellness trend

Selling drinking water in America began at resorts in New York and West Virginia, where tourists were encouraged to take the regenerative mineral water back to their homes.

Enhanced geothermal power systems can trigger earthquakes by injecting fluid into rock, increasing subterranean pressure.

The Geysers is the largest geothermal power complex in the world

Despite the Mayacamas Mountains area north of San Francisco lacking geysers, the name given by a grizzly bear hunter stuck after the construction of The Geysers Resort Hotel to accommodate tourists. Natural steam vents in the region are funneled into more than 12 geothermal plants, each capable of powering about 40,000 homes.

Early Native Americans shifted from nomadic life to permanent settlements around 8500 B.C.E.

Around 8500-7900 B.C.E., many Indigenous groups began settling near rivers and lakes to harvest fish and hunt bison, moving away from a fully nomadic lifestyle. This shift toward semipermanent communities marks one of the earliest signs of organized settlement in North America.

The first Americans arrived between 14,000 and 40,000 years ago

Early peoples migrated to the Americas via the Bering Land Bridge or coastal routes, spreading across the continent as hunter-gatherers. Archaeological sites in present-day New Mexico containing stone tools and animal bones mark some of the earliest confirmed evidence of human life in North America.

Yellowstone was the world's first national park

Before it was designated as such, it was home to 27 Indigenous tribes, including the Blackfeet, Crow, and Nez Perce. European trappers and traders traveling west were entranced by the area’s stunning beauty and natural resources, fueling a push for the government to preserve the land for future generations.

When did people start making and using glass?

This article details the search for the ancient origins of glass, a now-common item through which archaeologists can spot histories of trade and innovation. Bronze Age glass was made from crushed quartz instead of sand, and artisans could color glass with materials such as cobalt. These trace metallic add-ons have given scientists a vital clue into the origins of glass, which is currently debated as either Egypt or the Near East.

Why are archaeologists brewing ancient beers?

Archaeologists have managed to brew beer from yeast found inside jugs abandoned thousands of years ago. This article explores why scientists are recreating these ancient beverages and what they hope to learn. People have been drinking beer for...

A medieval warm period reshaped agriculture across parts of the world

Between 750 and 1350 CE, some regions experienced temperatures that rivaled or exceeded late-20th-century averages, likely due to shifts in El Niño–La Niña cycles. The warmer, wetter climate in Europe and northeast North America boosted agriculture, while causing droughts elsewhere.

Wealthy Egyptians slept on woven beds to allow air circulation in hot climates

The history of beds is a fascinating look at economics, social science, and cultural beliefs around what takes place during sleep. This brief survey of the history of bed-making begins roughly 5,000 years ago and runs through ancient Egypt and Rome to modern Europe. Take a look here.

Fascinating evolution of the oven

From ancient wood-fired ovens in Rome and Egypt to modern microwaves, the oven’s evolution has shaped how we cook. Early ovens focused on heat retention, but breakthroughs like the gas stove in 1834, and the electric stove in 1892, brought precision. Then, in 1967, the microwave redefined convenience.

Tour the ancient world via beer

What did the people of yesterday make of beer, and how exactly did they make it? Explore the timeless beverage in this guide to ancient beers from around the world. Archaeological evidence suggests the rise of beer brewing may have coincided with humanity's shift from hunters to farmers. According to this article, beer was first enjoyed in ancient Mesopotamia, where paintings, poems, and myths glorified the porridge-like brew.

Even in recent history, adaptations to the environment drove human evolution

Through genetics, environmental pressures, and cultural influences, humans have evolved to tolerate lactose, develop varying skin pigmentation, and acquire genetic resistance to diseases like bubonic plague. The metabolic and digestive systems of Indigenous peoples have adapted to their diet, which is influenced by the availability of food and water.

Heat pumps use an easily boilable chemical to regulate temperature

In air conditioners, warm air is pulled from a home to turn a refrigerant into a gas, which is then compressed, raising its temperature. The gas naturally releases this energy to the comparatively cooler environment when exposed, then expands and is reused in the system. Heaters run in reverse, with the refrigerant picking up energy from the comparatively warmer environment.

Some geothermal power plants make electricity using a secondary fluid

Direct dry-steam systems pull underground steam into a turbine-generator system, while flash and double-flash cycle systems spray extracted liquid water into a low-pressure tank, causing it to rapidly vaporize—"flash"—before moving to the turbine. Binary cycle systems use the extracted steam and water to flash a second fluid that easily boils, which then drives the turbine.

The history of metallurgy: an interactive timeline

Humans have long been shaping metals into useful tools and aesthetic accessories. By 8,700 BCE, humans already had mastered four types of casting copper. Within a few thousand years, people were combining metals to make the alloy bronze and had...

View thermophiles found in Hot Springs National Park, including nanobacteria and ostracods

Most organisms in this subset of extremophiles live at temperatures between 60 and 80 degrees Celsius (140 to 176 degrees Fahrenheit), which is hot enough to unfold proteins needed for most biochemical reactions. In thermophiles, these molecules, including those needed to replicate DNA during cellular division, are tightly packed and held by stronger bonds to resist changes in shape.

Many of Wright's buildings used radiant heating

Frank Lloyd Wright’s buildings weren’t just radical because of how they looked, but many of them also incorporated stunning technological innovations. Radiant heating is one of Wright’s most popular heating systems, offering the comfort of walking on warm floors on a cold day.

East Asian records of auroras may date back to 10,000 BCE

Ancient texts from Japan, Babylon, and China contain accounts of auroras dating back millennia. Because auroral activity and intensity are driven by periodic ebbs and flows in solar activity, these records allow scientists to identify patterns that may help anticipate particularly dangerous future solar storms.

The fast food shops of ancient Pompeii

Researchers have unearthed a frescoed thermopolium (a sort of hot food and drink shop) in Pompeii, the ancient Roman city frozen in time after the catastrophic eruption of Mount Vesuvius in 79 CE. This fascinating discovery provides a glimpse into Roman culinary practices and the daily life of Pompeii's citizens.

Mount Vesuvius' ancient Roman eruption may have literally boiled blood

Mount Vesuvius erupted in 79 CE, sending ash and debris far and wide, burying several cities and the people inside them. This article details the various ways the blast killed those in Herculaneum. This seaside town was hit with the same ash and debris as Pompeii, and it was also hit by a wave of volcanic gases estimated to be more than 500° Fahrenheit, about 260° Celcius.