Options for Kentucky’s energy independence
As part of an ongoing series of articles on renewable energy, Land, Air, and Water staff sits down with Assistance Director of Renewable Energy for a one to one discussion on Kentucky’s renewable energy landscape. In this issue, Kenya Stump discusses the power of wind in Kentucky.
Q: Is Kentucky a good state for wind energy?
KS: Not compared to our mid-western states but we do have pockets of wind resources where a project could make sense. To get a better sense for how we compare, there are wind resource maps. For instance, at the 80 meter height for utility scale projects, the map below shows our average wind speeds. You can see some pockets of tan and brown where our wind speeds are in the mid-range of the scale.
Most small wind turbines (<100 kW), need 3-4 meters/second of wind speed just to begin generating power. To reach their rated capacity, these turbines need upwards of 10 meters/second of wind speed, larger utility scale need upwards of 11-15 meters/second. And then there is the fact that the wind doesn’t blow all the time, that’s where we see capacity factors ranging from 25 to 50%, this is the percent of the potential generation that is actually achieved. This is highly dependent on location and turbine design.
Q: Does Kentucky have any wind energy projects?
KS: Yes, we have a few distributed small scale wind projects. In total for 2014, we had 16 small scale wind projects, totaling 56 kilowatts of installed capacity. For example, here are two in Mt. Sterling, Kentucky. On average, a 5 kW wind turbine would power a house and that would be at a height of anywhere between 30-140 ft. These turbines can range in cost between $5,000 and $70,000 depending on size, height, and installation costs.
Q: Why don’t we see more wind energy projects in those areas that can support it?
KS: For large scale projects (greater than 100kW), you have to remember the scale of these projects. With new technology, heights of turbines are exceeding 100 meters. At 110 meters, that is 360 feet tall or the length of a football field. The blades themselves are about 40 meters (130 ft.) in length and together these blades can sweep an area of 1-2 acres. That’s a lot of equipment and it’s not like they go un-noticed so it is understandable that communities have questions relating to noise and worry about the visual impact. During the 2014 General Assembly, House Bill 291 passed which established criteria for siting facilities such as wind turbines and establishing requirements for public meetings to inform and answer questions about proposed facility construction project. To assist communities, the Tennessee Valley and Eastern Kentucky Wind Working Group drafted a Model Wind Ordinance for use.
Q: What about noise, visual issues, and the environment?
KS: I think it is important to remember that there is no one perfect energy source. Every energy source and resulting technology has impacts to the environment and those around it. Wind is no different; but most impacts can be managed through proper community engagement and application of good siting criteria. Relating to the noise issue, most turbines are in the range of 40 to 50 decibels, which is about the level of sound generated from a window air conditioning unit or your refrigerator. From a wildlife perspective, research into wildlife behavior and advances in wind turbine technology has also helped to reduce bird and bat deaths. Visually, either people think they are graceful or an eyesore that obstructs the natural landscape. Altering the skyline for less polluting generation is a topic only the community can decide for themselves. Besides aesthetics, wind turbines can generate what is known as shadow flicker when the sun is positioned at low angles in the morning and afternoon; but siting criteria and best practices can mitigate this impact.
Q: So wind power isn’t really an option for Kentucky?
KS: Not necessarily. It is challenging at the local level but Kentucky can take advantage of the low cost wind generation that is coming out of the mid-western states. Right now, of the renewable energy resources, wind energy out of the mid-west is competitive with natural gas combined cycle plants and are getting combined capacity factors of close to 40-50%. What that means is that our utilities can add renewable energy resources to their portfolio at competitive prices, provided the transmission lines are there to bring it into the state.
Q: For someone looking at wind energy in Kentucky, what should they know?
KS: Just because it is windy where you live doesn’t mean you have enough resource for wind generation. To assess that, you need at least a year’s worth of anemometer readings to establish your wind resource level for all seasons. Typically, winds are strongest during winter and weakest during summer. For a small turbine less than 10 kW capacities, the prices of the turbine itself may not be enough to justify the investment of an anemometer tower which could be several thousand dollars. Finally, you want to look for a contractor who has wind energy project experience. The Department for Energy Development and Independence has a “Will Wind Work for Me?” guide available online for individuals, businesses, and organization. In addition, both the American Wind Energy Association and the U.S. Department of Energy’s WindExchange provide resources for project development.