Renewable energy systems have rapidly become more efficient and cheaper over the past 30 years. 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. From 2011 to 2021, renewable energy grew from 20% to 28% of global electricity supply. Power from sun and wind accounted for most of this increase, growing from a combined 2% to 10%. Use of fossil energy shrank from 68% to 62%. In 2022, renewables accounted for 30% of global electricity generation, and are projected to reach over 42% by 2028. Many countries already have renewables contributing more than 20% of their total energy supply, with some generating over half or even all their electricity from renewable sources.
The main motivation to replace fossil fuels with renewable energy sources is to slow and eventually stop climate change, which is widely agreed to be caused mostly by greenhouse gas emissions. In general, renewable energy sources cause much lower emissions than fossil fuels. The International Energy Agency estimates that to achieve net zero emissions by 2050, 90% of global electricity generation will need to be produced from renewable sources. Renewables also cause much less air pollution than fossil fuels, improving public health, and are less noisy.
The deployment of renewable energy still faces obstacles, especially fossil fuel subsidies, lobbying by incumbent power providers, and local opposition to the use of land for renewables installations. Like all mining, the extraction of minerals required for many renewable energy technologies also results in environmental damage. In addition, although most renewable energy sources are sustainable, some are not. For example, some biomass sources are unsustainable at current rates of exploitation. (Full article...)
The production of renewable energy in Scotland is a topic that came to the fore in technical, economic, and political terms during the opening years of the 21st century. The natural resource base for renewable energy is high by European, and even global standards, with the most important potential sources being wind, wave, and tide. Renewables generate almost all of Scotland's electricity, mostly from the country's wind power.
In 2020, Scotland had 12 gigawatts (GW) of renewable electricity capacity, which produced about a quarter of total UK renewable generation. In decreasing order of capacity, Scotland's renewable generation comes from onshore wind, hydropower, offshore wind, solar PV and biomass. Scotland exports much of this electricity. On 26 January 2024, the Scottish Government confirmed that Scotland generated the equivalent of 113% of Scotland's electricity consumption from renewable energy sources, making it the highest percentage figure ever recorded for renewable energy production in Scotland. It was hailed as "a significant milestone in Scotland's journey to net zero" by the Cabinet Secretary for Wellbeing Economy, Fair Work and Energy, Neil Gray. It becomes the first time that Scotland produced more renewable energy than it actually consumed, and demonstrates the "enormous potential of Scotland's green economy" as claimed by Gray.
Continuing improvements in engineering and economics are enabling more of the renewable resources to be used. Fears regarding fuel poverty and climate change have driven the subject high up the political agenda. In 2020 a quarter of total energy consumption, including heat and transportation, was met from renewables, and the Scottish government target is half by 2030. Although the finances of some projects remain speculative or dependent on market incentives, there has been a significant—and, in all likelihood, long-term—change in the underpinning economics. (Full article...)
"One of the new forces propelling renewable energy development is the potential to create new industries and generate millions of new jobs. Jobs from renewables now number in the hundreds of thousands in several countries. Germany, which has led renewable energy development for more than a decade, had more than 300,000 people employed in renewables industries in 2009, almost equaling the number of jobs in the country’s largest manufacturing sector, automobiles."
"Most of the large fiscal stimulus packages launched since late 2008 to combat the global recession have included significant funding for renewable energy. This has prevented a more pronounced economic downturn in the United States and has created a new industry almost from scratch in South Korea, which devoted four-fifths of its fiscal stimulus to the green economy. In total, nearly $200 million in green stimulus funding has been allocated to renewables and energy efficiency."
"The 1,230 gigawatts (GW) of renewable power generating capacity in place at the end of 2009 now constitutes just over 25 percent of total generating capacity worldwide. This is over three times nuclear generating capacity and roughly 38 percent of the capacity of fossil fuel-burning power plants worldwide."
... that the first recorded instance of solar distillation was by 16th century Arab alchemists? A large-scale solar distillation project was first constructed in 1872 in Chile a mining town of Las Salinas. The plant, which had a solar collection area of 4,700 m², could produce up to 22,700 L per day and operated for 40 years. Individual still designs include single-slope, double-slope (or greenhouse type), vertical, conical, inverted absorber, multi-wick, and multiple effect. These stills can operate in passive, active, or hybrid modes. Double-slope stills are the most economical for decentralized domestic purposes, while active multiple effect units are more suitable for large-scale applications.
The following are images from various renewable energy-related articles on Wikipedia.
Image 1Solar water heaters facing the Sun to maximize gain (from Solar energy)
Image 2Onshore wind cost per kilowatt-hour between 1983 and 2017 (from Wind power)
Image 3The Warwick Castle water-powered generator house, used for the generation of electricity for the castle from 1894 until 1940 (from Hydroelectricity)
Image 13Acceptance 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 14Global map of wind speed at 100 meters on land and around coasts. (from Wind power)
Image 15Geothermal power station in the Philippines (from Geothermal energy)
Image 16Concentrated 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 17A 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 27Merowe 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 29Installed geothermal energy capacity, 2022 (from Geothermal energy)
Image 30The Hoover Dam in the United States is a large conventional dammed-hydro facility, with an installed capacity of 2,080 MW. (from Hydroelectricity)
Image 31The oldest known pool fed by a hot spring, built in the Qin dynasty in the 3rd century BCE (from Geothermal energy)
Image 32Wind 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 36Seasonal 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 40Parabolic dish produces steam for cooking, in Auroville, India. (from Solar energy)
Image 41Enhanced 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 42Electricity generation at Ohaaki, New Zealand (from Geothermal energy)
Image 43Share of electricity production from hydropower, 2022 (from Hydroelectricity)
Image 44Electricity generation at Poihipi, New Zealand (from Geothermal energy)
Image 51Distribution 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 52Global map of wind power density potential (from Wind power)
Image 53Electricity generation at Wairakei, New Zealand (from Geothermal energy)