Renewable energy basics

Find out how much energy in the US comes from renewable sources and other FAQs

Browse frequently asked questions about renewables, from the amount of energy production by state to the cost of electricity generation by power source.

Wind energy 101

Learn more about the wind industry, from how a wind turbine works, to the new and exciting research in the field of wind energy.

Solar power is converting the sun's energy into thermal or electrical energy

Solar energy is the most abundant renewable energy resource. It can be captured in photovoltaic cells to generate electricity, solar heating and cooling technologies for temperature control, and concentrated solar power to drive steam turbines.

An overview of hydropower

Hydropower, or the use of the natural flow of moving water to generate electricity, is one of the oldest and largest sources of renewable energy.

View breakdowns of the world's and each nation's electricity comes from

These charts show how the shares of generated electricity sources—solar, wind, hydro, nuclear, bioenergy, oil, gas, and coal—have changed since 1985. Since 2010, an increase in renewable sources has offset the share lost by nuclear and fossil fuels.

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.

Wind turbines explained

Wind turbines have powered homes since 1887, and today they’re stronger, quieter, and more reliable than ever. Offshore wind could power millions and grow fast enough to meet climate goals.

Understanding the power grid and how renewable sources fit in

The power grid is evolving to include ever-higher levels of solar and wind, which don't provide inertia. Should system planners and operators panic?

Wind energy is categorized into land-based, distributed, and offshore types

Distributed wind turbines efficiently serve on-site energy needs, while land-based turbines are large and generate cost-competitive electricity. Offshore wind turbines capture powerful winds above the ocean and may be pounded into the seafloor using pile drivers or built to float above water at scales larger than the Statue of Liberty.

As of 2025, wave power projects remain in early research and testing phases

Waves can become a steady source of renewable energy because they do not pause like wind and solar power do. However, funding gaps and the effects of storms, salt exposure, and biofouling—mussels and other sea creatures attaching to wave machines—have presented challenges in scaling the technology beyond testing sites.

The world derives more of its energy from oil than from any other resource

Coal and gas are second and third, respectively, in terms of where the bulk of the world’s energy consumption stems from. These interactive charts can help you visualize where the world sources the most of its energy.

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.

Visualize energy sources and uses across the US

Want to understand the basics of America’s current energy situation? The National Academies, advisers to the nation on science, engineering, and medicine, provides objective information about the United States’ current energy sources and uses, as well as a look forward to the future of energy.

All clean energy technologies rely heavily on critical minerals

Although many of these minerals have been used for decades, such as copper in electrical wiring, the accelerating demand for them has strained existing extraction and processing systems. Supply chain disruptions for these materials may delay and increase the cost of transitioning to solar, wind, hydroelectric, and geothermal power.

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.

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.

Among renewable sources, geothermal rivals hydropower in lifetime cost

As of 2024, the levelized cost of energy—the average cost per unit of energy over the lifetime of a power plant—for geothermal power is surpassed only by solar photovoltaic and onshore wind. Geothermal's LCOE has remained relatively unchanged since 2007, with significant decreases held back by significant upfront installation costs.

Check out this interactive 3D animation of a virtual renewable energy-powered island

The US Department of Energy’s Renewable Energy Discovery (REDi) Island invite explorers to discover clean, renewable energy options by navigating a virtual island filled with energy efficient power generation and desalinization technologies.

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.

View a breakdown of global electricity generation in 2025, led by coal power plants.

Why is hydropower important when other power sources go dark?

Hydropower can ramp up, recoup shortfalls, and stabilize the grid nearly instantaneously. A new study quantifies the energy source’s contribution to grid stability.

Explore global solar resources with this interactive map

One of the biggest challenges to deploying solar panels is whether electricity can be generated reliably when needed, day after day. This detailed interactive map calculates the solar power output potential of regions worldwide and provides a visual comparison between locations such as North Africa and the US Midwest.

Artificial photosynthesis turns CO₂ into sustainable fuel

Carbon conversion focuses on a central perplexing question: if carbon dioxide is a leading driver of climate change, and fossil fuels are made of carbon-based molecules, can we devise a way to convert CO₂ into useful alternatives efficiently? This video breaks down a potential pathway using artificial photosynthesis, which uses sunlight to convert CO₂ into fuel.

View a photo essay of renewable power landscapes in China

Using a drone, Chinese photographer Weimin Chu captured the deployment of solar and wind power installations across the country, which accounted for half of all global installations in 2025. The images show modern infrastructure juxtaposed with natural landscapes and was featured in an award-winning exhibition presented by Greenpeace in 2025.

Clean energy technologies are more mineral-intensive than burning fossil fuels

Solar panels use silver due to its high conductivity, hydropower plants use chromium in their steel alloys, and geothermal plants need titanium to withstand abundant heat and pressure. Lithium—used in energy storage—is expected to see over 500% increased demand from 2020 to 2025.

What fuels the sun?

The sun is our biggest source of heat and light, but how does this massive powerhouse continue to produce such amazing energy? Basically, it's a fusion reactor. At its core the sun produces all that solar energy through hydrogen fusing and converting into helium, over and over again. Learn more about the entire amazing and explosive process here.

Solar energy alone can fully power the world if transmission hurdles can be resolved

When light strikes a photovoltaic cell, electrons are loosened, which travel through a circuit where the energy can be used. Distributing energy from high solar intensity regions and storing energy for non-daylight hours is logistically challenging and costly.

Wind is the movement of air caused by the sun's uneven heating of Earth

The tilt, curvature, and variations in Earth's surface composition across the globe cause different regions to receive different amounts of solar radiation. As the Earth spins and tries to achieve thermal equilibrium, air masses move and interact, creating wind.

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.)

Nuclear power supplies almost half of US carbon-free energy

As of 2023, nearly 20% of US electricity comes from nuclear power, but most reactors were built from 1971 to 1990. Expansion slowed due to safety concerns, high costs, and competition from natural gas.

View an illustrative guide to climate change for kids

While climates have changed throughout Earth's history, they are now changing faster than usual, driven by the burning of fossil fuels and the release of greenhouse gases, which trap more of the sun's radiation.

Why decarbonizing the entire electric grid is impossible with its current infrastructure

Fossil fuel plants can be built anywhere and have thus typically been built near highly populated areas, such as coastal cities, where electricity demand is high. However, certain renewable resources operate most efficiently in specific regions, such as wind turbines in the Midwest, and therefore require substantial transmission infrastructure to be constructed to transport the generated electricity.

Demystifying the claim that crude oil is inorganically created and a renewable resource

The abiogenic petroleum theory holds that fossil fuels originate in Earth's mantle and are constantly replenished, rather than formed by microorganisms over millions of years. While inorganic chemical processes can produce simple hydrocarbons, the range of complex molecules found in crude oil suggests an origin from a diverse set of organisms. Isotope analyses of these molecules also support the model that they originated from living things that preferentially take up certain isotopes over others.

Climate science 101: climate change, its impacts, and potential solutions

How do we know that this warming is happening and that it’s caused by humans? How strong is the evidence? What risks can we expect and what can we do about them?

What’s the best way to reduce climate impact of food?

Food is a big part of everyone’s carbon footprint, and it’s important to understand the impact of our personal food consumption. Individual food choices can emit as many greenhouse gases as personal electricity use. Plant-based diets generally...

China is the world’s largest importer of crude oil

China is pushing to reduce its reliance on US oil to limit geopolitical vulnerabilities. It’s rapidly becoming the world’s renewable energy superpower.

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.

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.

An overview of helium, the nonrenewable resource that's lighter than air

The second element in the periodic table naturally forms deep underground over the course of billions of years through the decay of radioactive elements, but it is used and lost to space at rates faster than it is generated. Because of this and its extensive applications in scientific technologies, scientists continue to seek avenues for its exploration, storage, and recycling.

Larger shares of solar power generation produce larger energy demand curves

Because solar energy is only available during daylight hours, transitioning an electric grid to solar requires significant ramp-ups and ramp-downs of other energy sources during mornings and evenings to compensate. Widespread adoption of affordable energy storage solutions can soften these curves.

The value of fracking is dependent on international energy markets

Russia's war in Ukraine spurred calls in the US to increase fracking, which has historically reduced dependence on foreign nations and increased national security. However, some experts argue that renewable energy provides even better energy independence, as fracking investments may not be worthwhile if importing fossil fuels is significantly cheaper.

The engineering underlying the electric grid and why it needs to be modernized

The system includes generators for producing electricity and millions of miles of transmission and distribution lines to transport the energy. The substantial increase in the number of electronic devices and electrical demand since the construction of much of the grid in the mid-1900s has strained infrastructure, requiring continuous upgrades and massive investments in new construction.

View an interactive map of US power plants, which generate electricity from coal, gas, water, biomass, nuclear fuel, oil, sunlight, and wind.

View US maps of average daily solar resources and solar-based electricity generation

The state you live in can drastically change how much solar energy you can expect to capture to power your home. These National Laboratory of the Rockies maps show where you can reliably generate solar resources.

Wind farms are targets for conspiracy theories due to their visibility and complexity

The proliferation of misinformation and conspiracy theories surrounding wind farms is driven by deep-seated anxieties about change, distrust of government, and resistance to confronting the complexities of modern energy solutions.

How the sun heats the Earth

We all know it: Without the sun's heat, the Earth would be uninhabitable. So how does it work? The sun fuses roughly 600 million tons of hydrogen every second, the energy from which bursts out into space—including toward our planet. Our atmosphere...

Cryptocurrency is reshaping finance, but its environmental impact often sparks debate

Behind the scenes, mining operations consume vast amounts of energy, comparable to the emissions of small nations. What drives this surprising environmental footprint, and can the industry evolve?

An overview of bioremediation, which can help clean up oil spills, mining waste, and some plastics

The umbrella term refers to a variety of techniques that use organisms to remove harmful substances from an environment or break them down into nontoxic compounds. Because the availability of certain resources can limit the growth of these organisms and impair bioremediation efforts, nutrients such as fertilizers can be deployed to accelerate cleanup.

Growing EV adoption requires battery management infrastructure

Despite rechargeable batteries' limited life cycle, companies like Spiers New Technologies have developed methods to repair, refurbish, repurpose and recycle these components to minimize environmental waste, lower demand for new critical minerals, and increase electric vehicle lifetimes.

Sand 'batteries' can store excess electricity from the power grid as thermal energy

Energy collected from solar or wind power is used to heat insulated silos full of sand to temperatures as high as 450 degrees Celsius (842 degrees Fahrenheit), which can be retained for long periods. These thermal energy storage systems can be designed to boil water and generate electricity when needed.