Renewable power is derived from natural resources that are replenished at a sustainable rate, such as solar, wind, geothermal, bioenergy, hydropower, and marine power.
In 2016, renewable energy accounted for over 23 percent of total global electricity production and is set to expand to 37 percent in 2040 against a background of global energy consumption growth of 48 per cent.
Most growth has come from largescale power stations, particularly hydro generators powered by huge dams.
At 22,500 MW, the Three Gorges Dam in Hubei, China, has the world's largest instantaneous generating capacity, with the Itaipu Dam in Brazil/Paraguay in second place at 14,000 MW.
These compare with the world’s largest solar photovoltaic (PV) farm, Kurnool Ultra Mega Solar Park in India, at 900 MW, and the largest wind farm in the world, Gansu in China, 6,000 MW as of 2012 and expanding to 20,000 MW by 2020.
Offshore wind power has been one of the biggest growth segments in the renewables sector over the last decade, with an entire industry – from service and maintenance of existing wind farms to the manufacturing of turbines – growing up around it.
After 50 GW of wind capacity was installed in 2014 and 60 GW in 2015 the wind industry consolidated in 2016, with 55GW capacity installed. At the end of 2016, total global installed capacity was nearly 487 GW.
Onshore wind is a relatively less expensive source of power, competitive with or in many places cheaper than coal or gas plants. Small onshore wind farms can feed some energy into the grid or provide electric power to isolated off-grid locations, but have faced increasing difficulties due to public concern over adverse health impacts and visual amenity.
Solar PV – manufactured cells that convert sunlight directly into electricity – is becoming increasingly significant in the global energy mix, as the cost of technology dropped dramatically. The cost of modules per kW fell from approximately $4,000 (€3,000) in 2007 to $468 (€500) in 2017.
Although there are sunnier parts of the world where the technology is more viable, such as Australia, California, India and Africa, solar PV is economical in northern hemisphere countries that receive less solar radiation, such as the UK and Germany, which have seen growth in small-scale, residential solar.
The size of large-scale solar PV power stations has increased steadily over the last decade, with frequent new capacity records. As of April 2017, India was home to the largest PV plant with 900 MW of the 1,000 MW already commissioned at the Kurnool Ultra Mega Solar Park.