There are many sources of renewable energy being implemented and investigated today. Renewable energy is energy that comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, and is naturally replenished. Over the next several weeks, this blog will identify and discuss a few of these sources. I hope to provide information regarding history, current state, current uses, and the future of the source. For this week, let’s start with one of the most popular sources of renewable energy, wind.
Wind power, as a renewable energy source, converts the natural energy created by wind into useful forms. The history of basic wind power goes back a long ways with the use of wind energy to propel sailboats and sailing ships and windmills for irrigation and milling purposes. In the U.S., the invention of the water-pumping windmill at the turn of the 19th century was of great importance because it allowed for farming and ranching in areas that otherwise lacked the necessary amount of readily available water while also provided energy to these isolated farms. The modern wind power industry began around the 1980s using wind turbines to generate electric power. Early wind turbines were capable of producing 20-30 kW of power.
Today, many of these wind turbines are erected groups to create wind farms. It is likely that you have been driving down the highway, particularly in rural America, and seen these large, windmill like structures in the middle of fields. A large wind farm may consist of several hundred turbines covering hundreds of square miles. While these wind farms use a lot of land, farmers are able to use the space in between for agricultural purposes and typically receive rental income for the use of the land. The annual energy production for a wind farm, since wind speed is not constant, can’t be calculated by simply multiplying the generator nameplate ratings by the total hours in a year. Instead, we use the capacity factor, the ratio of actual productivity to the theoretical maximum. Typical capacity factors range between 20%-40% efficiency. In addition, when compared to the environmental impact of traditional energy sources, the impact from wind farms is minor. Wind power uses no fuel, emits no air pollution, and the energy used in transporting and manufacturing equipment for construction is negated in just a few months of production.
The use of wind power has greatly increased since 2000. From 2000-2006, world wind generation capacity more than quadrupled, doubling nearly every three years. In the U.S. 94,650 GWh of electricity was generating using wind power in 2010, accounting for 2.3% of the total electricity generated in the country.
Other leading countries include:
Spain- 16% of total electricity generation
Future trends indicate that the wind power industry should continue to grow. China accounted for nearly half of all new wind installations in 2010, showing the industry is spreading outside its traditional markets of North America and Europe. Like most industries, wind power was hindered by the recent economic crisis, however BTM Consult, an independent consulting company specializing in renewable energy commercialization services, predicts substantial growth through 2013. For the past five years the average growth of new installations has been 27.6%. Although, as a result of the economic crisis, the predicted average annual growth rate through 2013 dips a little to 15.7%, it shows that the wind power industry will continue to rise. The U.S. Department of Energy is currently working with six leading wind turbine manufacturers towards achieving 20% wind power in the U.S. by 2030. In conjunction with the DOE, these manufacturers will collaborate on information in five major areas; research and development related to turbine reliability and operability, sitting strategies for wind power facilities, standards development for turbine certification and universal interconnection of wind turbines, manufacturing advances in design, process automation, and fabrication techniques, and workforce development.