Since the dawn of time, wind has been noted as powerful natural force. In fact, nearly every ancient religious system featured a deity or supernatural entity associated with wind.
It's no wonder, then, that humans have found ingenious ways to harness wind's considerable physical energy. From the ancient sails of very early civilizations in India, Egypt, and the Near East, to today's utility-scale wind farms, wind is potent source of clean, natural energy.
Unlike the fossil fuels that people have relied on since the Industrial Revolution, wind is not a finite resource. It's impossible to run out of wind, and its use doesn't release as much of the environmentally damaging byproducts associated with petroleum and coal processing. Starting with the oil crisis of the 1970's, wind has been one of several clean energy technologies at the forefront of a movement to decrease reliance on fossil fuels.
How Does Wind Power Work?
The most common modern method of harnessing wind energy to generate electricity is the use wind turbines.
A turbine is a rotary device that extracts energy from the motion of a fluid – in this case, the gases that make up our atmosphere – and converts that energy into useful work.
Imagine a fan, but reversed. Instead of using electricity to power a fan’s blades, a wind turbine uses the power of wind to generate electricity. The spinning blades turn a shaft that connects to a rotor. This action is what produces electricity.
In a wind turbine, blades serve to rotate a generator shaft, which produces electricity. Turbine blades are designed with a carefully calculated curvature to help them capture as much wind as possible. The kinetic energy from the spinning blades, caused by the wind, turns the central drive shaft.
In the presence of wind, a small area of low-pressure air forms on the downward side of the turbine blade. This low-pressure region draws the blade toward it, providing lift that exceeds the wind's drag against the front of the blade. Because wind speeds are higher and less turbulent above ground than at ground level, most utility wind turbines are mounted 100 feet or higher above ground. Ideal locations for wind farms experience relatively consistent wind speeds of about 16 – 20 MPH.
Small turbines are often used to provide off-the-grid power. (You may have seen these on top of billboards recently, where they provide electricity to light up the sign at night.) Much larger turbines are used to generate energy for the power grid. Wind farms consisting of a few hundred turbines can power an entire city.
Inside the main body of the turbine, called the "nacelle", the blades themselves can only turn the shaft at around 16 RPM. This speed isn't sufficient to provide electricity to a power grid, so rotating gears in a gearbox component convert this slow motion into 1600 RPM, turning the drive shaft quickly enough to generate electrical power.
Wind farms can be positioned either on land or offshore. Wind speeds at sea are significantly higher, making offshore wind farms more efficient than their landlocked counterparts. However, the logistics of building offshore wind farms and transporting electricity from them have been challenging.
Using Wind Farms to Power an Electrical Grid
The main application of modern wind farms is to generate usable electricity for a regional power grid.
The size, design, and rotor diameter of a wind turbine will determine how much power it can generate. Turbines have a designated rated capacity, based on how much power they can produce under optimal wind conditions. For example, a 2 kW turbine will produce 2 kWh of electricity per hour. A typical turbine is designed to function best at wind speeds of around 11 – 15 meters per second. Of course, wind speeds can vary significantly, so wind turbines usually produce about 10-40% of their rated capacity.
As wind turbine technology is continuously refined and improved, and more wind farms are constructed, wind power is expected to grow in importance. By 2030, the US Department of Energy plans to expand wind power to 20% of the nation's total generated electricity. This clean, environmentally friendly source of energy remains one of the most important alternatives to fossil fuels.
What Is Wind Energy?
Wind energy refers to the electricity generated from turbines that are spun by wind power alone.
What are the benefits of wind energy?
- Creates an influx of quality jobs: a jump from around 700,000 currently to over 1 million by 2025
- Reduces the costs spent on importing fossil fuels so those dollars can support domestic infrastructure
- Provides incentives for new businesses to invest in areas covered by clean energy due to available lower operational costs
What's a REC?
Renewable Energy Certificates (RECs) are tradable, non-tangible energy commodities that demonstrate 1 megawatt-hour (MWh) of energy was produced from a wind farm.
The more RECs that are purchased, the more valuable clean energy generation becomes, leading to more production and more renewable energy on the grid.
What happens when I switch to clean energy with Inspire?
We purchase renewable energy certificates from local, regional and/or national wind farms on your behalf to offset the energy that you consume every month.
Your utility company will still deliver the energy to your house, read your meters, and send you your bill. We are listed as the supplier and there is nothing else you have to do.
Your home or business will actively support more clean power getting into the grid without needing to change your lifestyle. It’s as simple as that!