Renewable energy

Renewable energy is energy from renewable resources that are naturally replenished on a human timescale. Renewable resources include sunlight, wind, the movement of water, and geothermal heat.[2][3] Although most renewable energy sources are sustainable, some are not. For example, some biomass sources are considered unsustainable at current rates of exploitation.[4][5] Renewable energy is often used for electricity generation, heating and cooling. Renewable energy projects are typically large-scale, but they are also suited to rural and remote areas and developing countries, where energy is often crucial in human development.[6][7] Renewable energy is often deployed together with further electrification, which has several benefits: electricity can move heat or objects efficiently, and is clean at the point of consumption.[8][9]

From 2011 to 2021, renewable energy grew from 20% to 28% of global electricity supply. Use of fossil energy shrank from 68% to 62%, and nuclear from 12% to 10%. The share of hydropower decreased from 16% to 15% while power from sun and wind increased from 2% to 10%. Biomass and geothermal energy grew from 2% to 3%. There are 3,146 gigawatts installed in 135 countries, while 156 countries have laws regulating the renewable energy sector.[10] [11] In 2021, China accounted for almost half of the global increase in renewable electricity.[12]

Globally there are over 10 million jobs associated with the renewable energy industries, with solar photovoltaics being the largest renewable employer.[13] Renewable energy systems are rapidly becoming more efficient and cheaper and their share of total energy consumption is increasing,[14] with a large majority of worldwide newly installed electricity capacity being renewable.[15] In most countries, photovoltaic solar or onshore wind are the cheapest new-build electricity.[16]

Many nations around the world already have renewable energy contributing more than 20% of their total energy supply, with some generating over half their electricity from renewables.[17] A few countries generate all their electricity using renewable energy.[18] National renewable energy markets are projected to continue to grow strongly in the 2020s and beyond.[19] According to the IEA, to achieve net zero emissions by 2050, 90% of global electricity generation will need to be produced from renewable sources.[20] Some studies have shown that a global transition to 100% renewable energy across all sectors – power, heat, transport and industry – is feasible and economically viable.[21][22][23] Renewable energy resources exist over wide geographical areas, in contrast to fossil fuels, which are concentrated in a limited number of countries. Deployment of renewable energy and energy efficiency technologies is resulting in significant energy security, climate change mitigation, and economic benefits.[24] However renewables are being hindered by hundreds of billions of dollars of fossil fuel subsidies.[25] In international public opinion surveys there is strong support for renewables such as solar power and wind power.[26][27] In 2022 the International Energy Agency asked countries to solve policy, regulatory, permitting and financing obstacles to adding more renewables, to have a better chance of reaching net zero carbon emissions by 2050.[28]