Renewable energy systems are rapidly becoming more efficient and cheaper. As a result, their share of global energy consumption is increasing. A large majority of worldwide newly installed electricity capacity is now renewable. In most countries, photovoltaic solar or onshore wind are the cheapest new-build electricity. Renewable energy can help reduce energy poverty in rural and remote areas of developing countries, where lack of energy access is often hindering economic development. Renewable energy resources exist all over the world. This is in contrast to fossil fuels resources which are concentrated in a limited number of countries.
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%. In 2022, renewables accounted for 30% of global electricity generation, up from 21% in 1985, and projected to reach over 42% by 2028.
Many countries around the world already have renewable energy contributing more than 20% of their total energy supply. Some countries generate over half their electricity from renewables. A few countries generate all their electricity from renewable energy. National renewable energy markets are projected to continue to grow strongly in the 2020s and beyond.
The deployment of renewable energy is being hindered by massive fossil fuel subsidies. In 2022 the International Energy Agency (IEA) requested all countries to reduce their policy, regulatory, permitting and financing obstacles for renewables. This would increase the chances of the world reaching net zero carbon emissions by 2050. According to the IEA, to achieve net zero emissions by 2050, 90% of global electricity generation will need to be produced from renewable sources.
Whether nuclear power is renewable energy or not is still controversial. There are also debates around geopolitics, the metal and mineral extraction needed for solar panels and batteries, possible installations in conservation areas and the need to recycle solar panels. Although most renewable energy sources are sustainable, some are not. For example, some biomass sources are unsustainable at current rates of exploitation. (Full article...)
Hoover Dam is a concretearch-gravity dam in the Black Canyon of the Colorado River, on the border between the U.S. states of Nevada and Arizona. Constructed between 1931 and 1936, during the Great Depression, it was dedicated on September 30, 1935, by President Franklin D. Roosevelt. Its construction was the result of a massive effort involving thousands of workers, and cost over 100 lives. In bills passed by Congress during its construction, it was referred to as the Hoover Dam, after President Herbert Hoover, but was named the Boulder Dam by the Roosevelt administration. In 1947, the name Hoover Dam was restored by Congress.
Since about 1900, the Black Canyon and nearby Boulder Canyon had been investigated for their potential to support a dam that would control floods, provide irrigation water and produce hydroelectric power. In 1928, Congress authorized the project. The winning bid to build the dam was submitted by a consortium named Six Companies, Inc., which began construction in early 1931. Such a large concrete structure had never been built before, and some of the techniques used were unproven. The torrid summer weather and lack of facilities near the site also presented difficulties. Nevertheless, Six Companies turned the dam over to the federal government on March 1, 1936, more than two years ahead of schedule.
Hoover Dam impounds Lake Mead and is located near Boulder City, Nevada, a municipality originally constructed for workers on the construction project, about 30 mi (48 km) south-east of Las Vegas, Nevada. The dam's generators provide power for public and private utilities in Nevada, Arizona, and California. Hoover Dam is a major tourist attraction, with 7 million tourists a year. The heavily traveled U.S. Route 93 (US 93) ran along the dam's crest until October 2010, when the Hoover Dam Bypass opened. (Full article...)
"Perhaps because of its technical, economic, and thermodynamic advantages, a renewable power sector would have six benefits over one reliant on conventional power plants, including (1) lower negative externalities per kWh, (2) more stable and predictable fuel prices, (3) fewer greenhouse gas emissions, (4) less water use, (5) improved efficiency, and (6) greater local employment and revenue." – Benjamin K. Sovacool and Charmaine Watts. The Electricity Journal, May 2009, Vol. 22, Issue 4, p. 99.
"... renewable electricity technologies present policy makers with a superior alternative for minimising the risk of fuel interruptions and shortages, helping improve the fragile transmission network and reducing environmental harm. These smaller and more environmentally friendly generators cost less to construct, produce power in smaller increments and need not rely on continuous government subsidies. They generate little to no waste, have less greenhouse gas emissions per unit of electricity produced and do not contribute significantly to the risk of accidents." – Benjamin K. Sovacool, Journal of Contemporary Asia, 40(3), 2010, p. 371.
... that the International Renewable Energy Agency (IRENA) to promote widespread and increased adoption and sustainable use of all forms or renewable energy was founded in 2009 ? Acting as the global voice for renewable energies, IRENA will facilitate access to all relevant renewable energy information.
IRENA's founding reflects a growing consensus among governments around the world on the need to speed up the commercialization of renewable energy worldwide. IRENA provides advice and support to governments on renewable energy policy, capacity building, and technology transfer. IRENA will also co-ordinate with existing renewable energy organizations, such as REN21.
The following are images from various renewable energy-related articles on Wikipedia.
Image 1Global geothermal electric capacity. Upper red line is installed capacity; lower green line is realized production. (from Geothermal energy)
Image 2Greenhouse gas emissions per energy source. Wind energy is one of the sources with the least greenhouse gas emissions. (from Wind power)
Image 3A turbine blade convoy passing through Edenfield in the U.K. (2008). Even longer 2-piece blades are now manufactured, and then assembled on-site to reduce difficulties in transportation. (from Wind power)
Image 4Electricity generation at Poihipi, New Zealand (from Geothermal energy)
Image 5Merowe Dam in Sudan. Hydroelectric power stations that use dams submerge large areas of land due to the requirement of a reservoir. These changes to land color or albedo, alongside certain projects that concurrently submerge rainforests, can in these specific cases result in the global warming impact, or equivalent life-cycle greenhouse gases of hydroelectricity projects, to potentially exceed that of coal power stations. (from Hydroelectricity)
Image 6Geothermal power station in the Philippines (from Geothermal energy)
Image 10Parabolic dish produces steam for cooking, in Auroville, India. (from Solar energy)
Image 11Share of electricity production from hydropower, 2022 (from Hydroelectricity)
Image 12Installed geothermal energy capacity, 2022 (from Geothermal energy)
Image 13Hydro generation by country, 2021 (from Hydroelectricity)
Image 14The Hoover Dam in the United States is a large conventional dammed-hydro facility, with an installed capacity of 2,080 MW. (from Hydroelectricity)
Image 25Acceptance of wind and solar facilities in one's community is stronger among U.S. Democrats (blue), while acceptance of nuclear power plants is stronger among U.S. Republicans (red). (from Wind power)
Image 26Concentrated solar panels are getting a power boost. Pacific Northwest National Laboratory (PNNL) will be testing a new concentrated solar power system – one that can help natural gas power plants reduce their fuel usage by up to 20 percent.[needs update] (from Solar energy)
Image 27A panoramic view of the United Kingdom's Whitelee Wind Farm with Lochgoin Reservoir in the foreground. (from Wind power)
Image 29Global map of wind speed at 100 meters on land and around coasts. (from Wind power)
Image 30Yearly hydro generation by continent (from Hydroelectricity)
Image 31Distribution of wind speed (red) and energy (blue) for all of 2002 at the Lee Ranch facility in Colorado. The histogram shows measured data, while the curve is the Rayleigh model distribution for the same average wind speed. (from Wind power)
Image 36The Warwick Castle water-powered generator house, used for the generation of electricity for the castle from 1894 until 1940 (from Hydroelectricity)
Image 37Greenhouses like these in the Westland municipality of the Netherlands grow vegetables, fruits and flowers. (from Solar energy)
Image 48Wind turbines such as these, in Cumbria, England, have been opposed for a number of reasons, including aesthetics, by some sectors of the population. (from Wind power)
Image 49Global map of wind power density potential (from Wind power)
Image 50Electricity generation at Wairakei, New Zealand (from Geothermal energy)
Image 51Seasonal cycle of capacity factors for wind and photovoltaics in Europe under idealized assumptions. The figure illustrates the balancing effects of wind and solar energy at the seasonal scale (Kaspar et al., 2019). (from Wind power)
Image 52Enhanced geothermal system 1:Reservoir 2:Pump house 3:Heat exchanger 4:Turbine hall 5:Production well 6:Injection well 7:Hot water to district heating 8:Porous sediments 9:Observation well 10:Crystalline bedrock (from Geothermal energy)
Image 53Solar water heaters facing the Sun to maximize gain (from Solar energy)