Courtesy : Development of alternative energy such as solar
Wind power
Main article: Wind power
Wind energy generation by region over time.[68]
Global map of wind power density potential.[69]
| Global electricity power generation capacity | 824.9 GW (2021) |
| Global electricity power generation capacity annual growth rate | 13% (2012-2021) |
| Share of global electricity generation | 5% (2018) |
| Levelized cost per megawatt hour | Land-based wind: USD 30.165 (2019) |
| Primary technology | Wind turbine |
| Other energy applications | Windmill, windpump |
Air flow can be used to run wind turbines. Modern utility-scale wind turbines range from around 600 kW to 9 MW of rated power. The power available from the wind is a function of the cube of the wind speed, so as wind speed increases, power output increases up to the maximum output for the particular turbine. Areas where winds are stronger and more constant, such as offshore and high-altitude sites, are preferred locations for wind farms. Typically, full load hours of wind turbines vary between 16 and 57 percent annually but might be higher in particularly favorable offshore sites.
Wind-generated electricity met nearly 4% of global electricity demand in 2015, with nearly 63 GW of new wind power capacity installed. Wind energy was the leading source of new capacity in Europe, the US and Canada, and the second largest in China. In Denmark, wind energy met more than 40% of its electricity demand while Ireland, Portugal and Spain each met nearly 20%.
Globally, the long-term technical potential of wind energy is believed to be five times total current global energy production, or 40 times current electricity demand, assuming all practical barriers needed were overcome. This would require wind turbines to be installed over large areas, particularly in areas of higher wind resources, such as offshore. As offshore wind speeds average ~90% greater tha ces can contribute substantially more energy than land-stationed turbines. # ISO certification In India
Hydro power
Main articles: Hydroelectricity and Hydropower
The Three Gorges Dam on the Yangtze River in China
| Global electricity power generation capacity | 1,230.0 GW (2021) |
| Global electricity power generation capacity annual growth rate | 2.5% (2012-2021) |
| Share of global electricity generation | 16% (2018) |
| Levelized cost per megawatt hour | USD 65.581 (2019) |
| Primary technology | Dam |
| Other energy applications | Pumped storage, mechanical power |
Since water is about 800 times denser than air, even a slow flowing stream of water, or moderate sea swell, can yield considerable amounts of energy. Water can generate electricity with a conversion efficiency of about 90%, which is the highest rate in renewable energy.There are many forms of water energy:
- Historically, hydroelectric power came from constructing large hydroelectric dams and reservoirs, which are still popular in developing countries. The largest of them are the Three Gorges Dam (2003) in China and the Itaipu Dam (1984) built by Brazil and Paraguay.
- Small hydro systems are hydroelectric power installations that typically produce up to 50 MW of power. They are often used on small rivers or as a low-impact development on larger rivers. China is the largest producer of hydroelectricity in the world and has more than 45,000 small hydro installations.
- Run-of-the-river hydroelectricity plants derive energy from rivers without the creation of a large reservoir. The water is typically conveyed along the side of the river valley (using channels, pipes and/or tunnels) until it is high above the valley floor, whereupon it can be allowed to fall through a penstock to drive a turbine. A run-of-river plant may still produce a large amount of electricity, such as the Chief Joseph Dam on the Columbia River in the United States. However many run-of-the-river hydro power plants are micro hydro or pico hydro plants. # ISO certification In India
Hydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010.[needs update] Of the top 50 countries by percentage of electricity generated from renewables, 46 are primarily hydroelectric. There are now three hydroelectricity stations larger than 10 GW: the Three Gorges Dam in China, Itaipu Dam across the Brazil/Paraguay border, and Guri Dam in Venezuela. Much hydropower is flexible, thus complementing wind and solar. # ISO certification In India
Wave power, which captures the energy of ocean surface waves, and tidal power, converting the energy of tides, are two forms of hydropower with future potential; however, they are not yet widely employed commercially. A demonstration project operated by the Ocean Renewable Power Company on the coast of Maine, and connected to the grid, harnesses tidal power from the Bay of Fundy, location of the world’s highest tidal flow. Ocean thermal energy conversion, which uses the temperature difference between cooler deep and warmer surface waters, currently has no economic feasibility. # ISO certification In India