Wind energy powering America
Learn the wind energy basics and how the state of Pennsylvania is using them to its advantage.
Monday, July 5, 2010 - 13:17
Photo: Ned Lyttelton/Flickr
Wind energy is a converted form of solar energy, which is caused by the uneven heating of the atmosphere by the sun, the irregularities of Earth's surface and rotation of Earth.
Wind flow patterns are modified by Earth's terrain, bodies of water and vegetation. Humans use wind to their advantage for many purposes including sailing, flying kites, and most importantly, generating electricity. The terms "wind energy" or "wind power" describe the process where wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in 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.
How do wind turbines make electricity?
A wind turbine works the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
Modern wind turbines fall into two basic groups: the horizontal-axis variety and the vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor. Horizontal-axis wind turbines typically either have two or three blades. These three-bladed wind turbines are operated "upwind," with the blades facing into the wind.
What are the environmental benefits of wind power?
Wind energy system operations do not generate air or water emissions and do not produce hazardous waste. Nor do they deplete natural resources such as coal, oil or gas, or cause environmental damage through resource extraction and transportation, or require significant amounts of water during operation. Wind's pollution-free electricity can help reduce the environmental damage caused by power generation in the U.S. and worldwide.
Development of just 10 percent of the wind potential in the 10 windiest U.S. states would provide more than enough energy to displace emissions from the nation's coal-fired power plants and eliminate the nation's major source of acid rain; reduce total U.S. emissions of CO2 by almost a third; and help contain the spread of asthma and other respiratory diseases aggravated or caused by air pollution in this country.
If wind energy were to provide 20 percent of the nation's electricity — a very realistic and achievable goal with the current technology — it could displace more than a third of the emissions from coal-fired power plants.
What are wind power's negative environmental impacts?
Wind power plants, like all other energy technologies, have some environmental impacts. However, unlike most conventional technologies (which have regional and even global impacts due to their emissions and fuel imports), the impacts of wind energy systems are minimal and local. This makes them easier for local communities to monitor and, if necessary, mitigate. The local environmental impacts that can result from wind power development include: erosion, deaths of birds/bats, noise, visual impacts and shadow flicker.
Will using more wind energy help to slow climate change?
Yes! Wind power is a clean, renewable form of energy, which during operation produces no carbon dioxide. While some emissions of these gases will take place during the design, manufacture, transport and erection of wind turbines, enough electricity is generated from a wind farm within a few months to totally compensate for these emissions. When wind farms are dismantled (usually after 20-25 years of operation) they leave no form of pollution for future generations. Wind power being the least expensive, most developed renewable energy technology and the fastest to build is the best placed renewable technology to deliver carbon emissions reductions on a large scale, quickly.
Where does Pennsylvania stand in the development of wind energy?
Act 213 of 2004, the Alternative Energy Portfolio Standards Act, signed into law by Governor Edward G. Rendell on November 30, 2004, required that 18 percent of the electricity sold to retail customers in Pennsylvania come from renewable and advanced energy sources within 15 years. Act 213 brought both environmental and economic benefits to the Commonwealth of Pennsylvania, and positioned the state as a national leader in alternative and renewable energy development.
The mission of the Pennsylvania Wind and Wildlife Collaborative is to engage federal and state environmental agencies, nongovernmental conservation organizations, and the wind industry in a collaborative, consensus-based process to collect, share, review and use the best available science, data and professional expertise to address how best to assist in the development of wind energy in Pennsylvania in an environmentally responsible manner. By capturing one of Pennsylvania's most bountiful natural resources — the wind — and turning it into clean electricity, the Commonwealth creates new economic opportunities and creates high quality jobs, tax payments to local governments and lease payments to farmers. Moreover, shifting a significant portion of generation to wind energy can help reduce state’s dependence on strip mining and burning coal. Below is a selected few of the wind turbine operations successful in the state of Pennsylvania:
1) Bear Creek
Owner/Operator: Wind Park Bear Creek LLC
Output: 24 MW
No. of Turbines: 12 (Gamesa 2.0 MW)
Operational Since: February, 2006
Owner/Operator: FPL Energy
Output: 64.5 MW
No. of Turbines: 43 (GE 1.5 MW)
Operational Since: October 2003
3) Green Mountain
Owner/Operator: FPL Energy
Output: 10.4 MW
No. of Turbines: 8 (Nordex 1.3 MW)
Operational Since: May 2000
4) Mill Run
Owner/Operator: FPL Energy
Output: 15 MW
No. of Turbines: 10 (GE 1.5 MW)
Operational Since: November 2001
Turbines and power lines: Jacqui Sadler/Flickr
Thermometer image: Lourdes272/Flickr