Wind turbines convert kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity. A typical horizontal wind machine is as tall as a 20-story building. Wind machines need to be very tall to capture enough wind to generate large amounts of electricity. An average wind speed of only 14 miles (22.5 kilometers) per hour is needed to convert wind energy into electricity.
Wind energy is gaining popularity around the world. Scotland, for example, is home to the UK’s largest wind farm, in addition to two huge offshore wind turbines and several other onshore wind farms. Scotland’s windy climate makes it the perfect spot for successful wind turbines. Scottish wind turbines provided 846,942-megawatt hours of electricity, enough to supply the power needs of 93 percent of households, according to WWF Scotland.
China, which has a vast amount of land and a long coastline, wind power has great potential to generate power for the country’s large population. Around 80 wind farms are currently operating in China, and many Chinese companies are building wind turbines and their accompanying components. However, the country is experiencing some problems with wind power, because not all its current wind power capacity is connected to its power grids, meaning some wind power is lost. As part of its renewable energy targets, The National Development and Reform Commission, a department of China's State Council, aims to increase wind capacity to 200 GW by the end of 2020, up from 96 GW in 2014.
Wind power has a high initial cost – building the turbines, towers and foundations is expensive. However, wind energy is becoming more affordable as technology improves. According to the International Renewable Energy Agency (IRENA) the cost of generating wind energy dropped 23% since 2010 which if it continues could make renewable energy competitive by 2020.
Some critics of wind energy say that wind turbines are unsightly. Industry professionals work to minimize this issue by using computer simulations to evaluate the visual impact before construction beings and by using turbines that are the same size and spacing them out evenly.