Wind energy was used to propel boats along the Nile River as early as 5,000 BC. By 200 BC, simple wind-powered water pumps were used in China, and windmills with woven-reed blades were grinding grain in Persia and the Middle East. By the 11th century, people in the Middle East were using windpumps and windmills extensively for food production. Merchants and the Crusaders brought wind technology to Europe. The Dutch developed large windpumps to drain lakes and marshes in the Rhine River Delta. Immigrants from Europe eventually took wind energy technology to the Western Hemisphere.
In 2019, hydropower usually refers to dams that have been built to generate electricity. Hydroelectric power accounts for about 19% of the world’s electricity, according to the BP Statistical Review of World Energy 2018.
Globally, hydropower supplies nearly one-fifth of the world’s energy each year, making it the most commonly used renewable energy source. Hydroelectric power generates more electricity worldwide than solar, wind, biomass and all other renewable sources combined.
Developing countries, including Brazil and China, needed an affordable, reliable and a sustainable source of electricity to support rapid economic growth. Since 2000, China has more than quadrupled its installed capacity to 341 GW (2017), accounting for over half of the world’s hydropower capacity growth.
Hydropower may be gaining popularity. China’s Three Gorges Dam produced a record breaking 98.8 terawatt hours of electricity in 2014. In 2016, the record was broken by Itaipu Dam on the Paraná River, by producing 103.1 terawatt hours.