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Summer 2007 Newsletter

In this issue:

Wind energy - powering a cleaner future

For centuries, the wind has powered human progress. From the first sailing ships that harnessed currents of air to connect the world, to windmills that helped farmers work and communities thrive, to a pair of aspiring brothers who took to the skies on the wings of their dream, wind power has shaped our history and improved our lives. And now, wind power may well help to preserve our future.

Wind turbines are one of the fastest growing energy technologies in America today. An affordable, clean and sustainable technology, wind power provides opportunities for both residential and utility-scale applications. Nationwide, wind turbine installations are growing at a rate of about 25 percent annually, with an estimated 3,000 MW of new wind power expected to be brought online in 2007. By the end of the year, it is projected that more than 3 million homes in America will be powered by wind-generated electricity.

Sized for success

Wind turbines come in a variety of sizes and designs. Small or residential-scale turbines typically range in height from 60-100 feet and have blade diameters ranging from 10 to 60 feet. Small turbines are often used as off-grid units, providing power for one or more homes outside of utility infrastructures. But they can also be used to supply the electric grid for use by everyone. Small wind systems are attractive to residential customers because of their relatively low price and scalability.

Large-scale wind turbines are used to supply electricity to the power grid for use on a utility scale. Turbines are typically around 200-300 feet high and have blade diameters of around 300 feet. One large-scale wind turbine can typically power more than 400 homes. Wind turbines of this size are often grouped into "farms," harnessing favorable wind resources collectively and providing electricity output equal to traditional power plants.

Regardless of size, wind turbines are designed with similar components to harness the potential of the wind. Each turbine contains blades which capture the movement of the wind to spin a rotor, upon which they are mounted. As the rotor spins from the force of the wind, it spins a shaft. The shaft then transfers the kinetic energy from its own rotation into a generator, which in turn makes electricity. Wiring systems transfer that electricity to the power grid for use by utility customers.

Wind energy and the environment

A wind turbine can provide years of sustainable, emissions-free energy. Modern aerodynamic designs make them very quiet and efficient. And years of design innovations have made them reliable and safe. Some concern has been raised as to their impact on birds and other airborne populations. While it is always important to pay careful consideration to the impacts of renewable technologies, recent studies have helped to put this concern in perspective.

A 2001 study on avian deaths by the National Wind Coordinating Collaborative indicated that approximately 33,000 birds were killed annually in strikes with wind turbines. More than 50 million died each year through impacts with automobiles and more than 100 million from impacts with buildings and other structures. The common domestic cat was responsible for hundreds of millions more each year.

While the number of bird deaths impacted by wind turbines is relatively low, it is still essential to pay careful attention to siting when developing wind projects in order to avoid migratory routes. Special consideration should also be given to local bat populations, which also seem to be vulnerable to encounters with wind turbines. When thinking of energy impacts on wildlife, it is also prudent to consider how many deaths occur from loss of habitat caused by fossil fuel emissions and other pollutants.

Wind power challenges

North Carolina offers one of the most promising locations on the East Coast for wind power development. The state possesses the best wind resources in the Southeast, with excellent siting located along ridge lines in the west and near the sounds and coastal areas in the east. But despite the excellent potentials of each region, challenges exist for future wind turbine development in North Carolina.

In the west, the N.C. Mountain Ridge Protection Act of 1983 limits construction on ridge lines above 3000 feet and whose elevation is 500 feet above a valley floor. While the act is useful for protecting natural viewsheds from development and preserving ridgelines, it also creates obstacles for wind turbine development. Most of the best wind areas in western North Carolina fall into zones protected by the Ridge Protection Act.

While state lawmakers continue to debate the future of wind power in western North Carolina and the impact that the Ridge Protection Act will have on such development, local lawmakers have recently begun taking their own actions. Watauga County commissioners recently passed regulations allowing for some limited wind turbine development in their area. The Ridge Protection Act does allow for this type of legislation on a local level and some communities are currently exploring these possibilities.

While Eastern North Carolina offers some easier opportunities for siting and permitting wind turbines, challenges in that region center around the environment. The best wind potential in the region is located on or near the ocean and sounds. While many of these areas are located relatively close to transmission lines to distribute the electricity, they are also prone to hurricanes and other adverse weather.

The high winds and damaging waters associated with hurricanes and tropical storms could easily damage ocean-based off-shore wind turbines or those located on the coast. To combat this, wind developers may well look inland to farmland in coastal regions or even in and around the sounds.

The advantage of sounds, such as the Albemarle and Pamlico Sounds in the northeastern portion of the state, are that they offer exceptional wind levels and shelter from the more brutal wind and tidal surges of the beaches and open ocean. An additional benefit of siting in these areas is that much of the land surrounding them is relatively undeveloped, offering fewer permitting issues and greater flexibility of scale and design.

A better future

Regardless of the location of projects in North Carolina or their size, wind power holds great promise for the state. From residential to utility-scale applications wind turbines can provide years of clean, reliable energy that can benefit local and state economies, reduce dependence on out-of-state fuel sources and lessen reliance on fossil fuels as a primary source of electricity.

The future of wind power in this state begins with the projects now producing renewable energy for NC GreenPower, and the many others in development or in discussion across the state. Ultimately, the success of wind energy in North Carolina will depend on the cooperation of lawmakers, electric utilities, energy advocates and the citizens of this state. Together, we can create a future that is built on the winds of change.