Renewable energy
Energy from replenished natural resources, increasingly replacing fossil fuels.
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Renewable energy, also called green energy, is energy made from renewable natural resources that are replenished on a human timescale. The most widely used types are solar energy, wind power, and hydropower, with bioenergy and geothermal power also significant in some countries. Renewable energy installations can be large or small and are suited for both urban and rural areas, often deployed together with further electrification to move heat and vehicles efficiently and cleanly at the point of consumption. For an energy source to be considered renewable, it must be endless; nuclear power, reliant on non-renewable fuel, is therefore not classified as renewable, though some debate this classification.
Technical potential
Renewable energy systems have rapidly become more efficient and cheaper over the past 40 years, with a large majority of newly installed global electricity capacity now coming from renewables. Solar and wind power have seen significant cost reductions, making them competitive with fossil fuels; in some locations, photovoltaic solar or onshore wind is the cheapest new-build electricity. From 2011 to 2021, renewable energy’s share of global electricity supply grew from 20% to 28%, with solar and wind rising from a combined 2% to 10%, while fossil fuel use shrank from 68% to 62%. By 2025, renewables accounted for over 30% of global electricity generation, with projections exceeding 45% by 2030.
Role in addressing climate change
Many countries already source over 20% of their total energy from renewables, and some generate more than half or all of their electricity this way. The main motivation for replacing fossil fuels with renewables is reducing greenhouse gas emissions that cause climate change; renewables generally pollute much less than fossil fuels, cause far less air pollution, improve public health, and are less noisy. The International Energy Agency estimates that to achieve net zero emissions by 2050, 90% of global electricity must come from renewables, though current expansion remains far from this pace, including in major economies like the G7 and EU. Obstacles to deployment include fossil fuel subsidies, lobbying by incumbent power providers, local opposition to land use, and environmental damage from mineral extraction required for many technologies.
Quick Facts
- Definition
- Energy from natural processes replenished faster than consumed
- Main types
- Solar
- wind
- hydropower
- bioenergy
- geothermal
- Key motivation
- Reduce greenhouse gas emissions causing climate change
Facts from the source article.
Lore & Background
Renewable energy, also termed green energy, is derived from natural resources that are replenished on a human timescale. The most common types are solar energy, wind power, and hydropower, with bioenergy and geothermal power also significant in certain countries. Installations vary widely in scale, from small units to large facilities, and are suitable for both urban and rural settings. A key characteristic is that renewable energy is often paired with further electrification, allowing electricity to efficiently power heating, cooling, and vehicles while remaining clean at the point of use.
Sources are divided into variable types—such as wind and solar, which fluctuate—and controllable types, including dammed hydroelectricity, bioenergy, and geothermal power. For a source to be considered renewable, it must be endless; nuclear power is excluded because it relies on non-renewable uranium fuel. Over the past four decades, renewable systems have become markedly more efficient and affordable.
By 2025, renewables accounted for over 30% of global electricity generation, with projections reaching over 45% by 2030. Many countries now source more than 20% of their total energy from renewables, and some generate over half or all of their electricity this way. The primary motivation for adopting renewables is reducing greenhouse gas emissions that drive climate change; they also produce far less air pollution, improving public health, and are quieter than fossil fuels. However, deployment faces obstacles including fossil fuel subsidies, lobbying by incumbent providers, local opposition to land use, and environmental damage from mineral extraction required for many technologies.
Reader's Guide
Renewable energy is central to addressing climate change, as its main motivation is to reduce greenhouse gas emissions. The International Energy Agency estimates that to achieve net zero emissions by 2050, 90% of global electricity will need to be generated by renewables. However, the current pace of renewable expansion remains far from this required rate globally, including in major economies such as the G7 and the EU.
Renewable energy also brings health benefits by reducing air pollution, with potential worldwide savings in health care costs estimated at trillions of dollars annually. It is more evenly distributed around the world than fossil fuels. Deployment still faces obstacles, including fossil fuel subsidies, lobbying by incumbent power providers, local opposition to land use, and environmental damage from mineral extraction.
Solar and wind are intermittent energy sources, requiring energy storage, demand response, or grid improvements. Pumped-storage hydroelectricity accounts for more than 85% of all grid power storage, while batteries and green hydrogen are increasingly used. The European Union aimed in 2022 to generate 40% of its electricity from renewables by the same year, and by 2025, 47% of EU electricity generation was by renewables.
Frequently Asked Questions
What is Renewable energy in the Energy & Power series?
Renewable energy (sometimes called green energy) is the entry that draws its power from natural processes—like sunlight, moving air, flowing water, or underground heat—that replenish far faster than humanity uses them. It is the long-running rival to fossil-fuel-based entries in the global electricity storyline.
How large is Renewable energy's share of the global electricity plot by 2025?
By 2025 it supplies over 30 percent of all electricity generated on Earth. Analysts project that figure will climb past 45 percent by 2030, cementing its role as the dominant source in the series.
How did Renewable energy's arc change between 2011 and 2021?
During that decade its slice of the global electricity pie grew from roughly 20 percent to 28 percent. Over the same stretch, the fossil-fuel entries' combined share slipped from about 68 percent down to 62 percent, marking a clear shift in the power balance.
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Sources
Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.
- Wikipedia: Renewable energy (CC BY-SA 4.0).
- Word definitions: the Codexery glossary, each quoted from its Wikipedia article.
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