Adoption Hurdles and Challenges with Small Wind Turbines|
Article - January, 4 2016 By LarsonElectronics.com
Adoption Hurdles and Challenges with Small Wind Turbines
Wind energy is very promising. It can be harvested without any costs, and like solar panels, wind turbines are environmentally-friendly. However, such machines are not living up to their potential. Some users have reported low efficiency rates, unpredictable performance and costly adoption barriers.
This article dives into the challenges of wind energy, with focus on small wind turbines. Read on to understand the type of location that wind turbines favor and how they affect animals.
Not Enough Suitable Locations
Small wind turbines need constant wind to generate power. Most people don’t understand the type of conditions required to keep such machines operating smoothly. To put things into perspective, a small turbine at 6 kW will need roughly 11 mph of wind (passing through the turbine’s height). When considering the viability of installing wind turbines, location is crucial. Unfortunately, only 20 percent of the United States support conditions above the 11 mph (5 m/s) threshold. These areas are mostly in the following states: Kansas, Colorado, Nebraska, Wyoming and parts of Texas. Such locations are filled with wide open spaces and farmland, which are suitable locations for solar power. With this in mind, cities that want to leverage the benefits of wind power will need to rely on lengthy transmission lines, connecting the wind farm to the city.
According to Solacity Inc., for every 100 homeowners, 85 are likely to have suitable locations for solar energy. For wind energy, only one homeowner is likely to live in an area that meets wind energy requirements.
Reliability and Laminar Wind
Small wind turbines in populated residential and commercial spaces are simply not ideal, due to several reasons. Poorly maintained wind turbines are loud and often come with a clicking noise, which can disrupt nearby neighbors. Meticulous maintenance or continuous replacement are the only two options to ensure quiet operation. This is because, unlike solar panel systems, small wind turbines are filled with moving parts. The rotor blades are constantly moving, and rough vibrations can easily contribute to loose nuts and bolts.
For consistent performance, turbines need laminar wind. Such conditions do not exist below 30 feet in height; and at 60 feet, it is rare. A height of 80 to 100 feet (or higher) is required to be able to take advantage of laminar wind. Hence, small residential turbines installed on rooftops or close to trees and other obstructions are likely not generating ample amounts of power. A solution to this issue is to install tall towers to support the machines. If you’re interested in capturing laminar wind at 100 to 150 feet, the tower could be your costliest investment. But with a 30-foot tower contributing zero percent of increased wind power and a 120-foot tower contributing 100 percent of increased wind power (150-foot tower equates to 124 percent of increased wind power), it might be worth it.
Installing a fleet of small turbines may seem harmless, but not for nearby animals. In particular, birds are prone to flying into rotor blades during operation. This is why locations with strict wildlife regulations prefer solar energy systems over wind turbines. Farmers that train birds to feed on pests and rodents are also more inclined to choose solar energy. There are ways to prevent birds from running into wind turbines, but such efforts usually entail pushing animals away from the location. This is not an option for locations that are in direct bird migration paths or routes.
According to a report released by the American Wind Wildlife Institute, song birds make up over 60 percent of deaths in wind turbine facilities. Furthermore, over 21 species of bats are prone to collision fatalities with rotor blades. Scientists speculate that the tiny animals may be attracted to the sound the machine makes, as well as to concentrated levels of insects around the tower. Water birds and other animals near open water and coastal regions are infrequently associated with wind turbine-related fatalities. Interestingly, large-capacity wind turbines (at 500 kW or greater) are safer for birds, because they require fewer rotations and the type of tower needed to support such structures deter perching.
Wind versus Solar
Compared to small wind turbines, solar panels come with several advantages for consumers. Without any moving parts, they are less prone to breakage and maintenance. Solar panels can also be installed on rooftops without intrusive towers. Since most locations in the US (based on Solacity’s findings above) are suitable for solar, risks related to low energy generation are minimal.
But does this mean that consumers should avoid wind energy? The answer is no. As long as the target location is conducive and optimized for small wind turbines, it would be possible to generate an overflow of power to meet one’s objectives.