One of the most fascinating aspects regarding wind turbines these days is in the height of the towers. Most of these turbines sit on very tall towers, some as much as even 65 meters in height. So, why is it that the usage of these tall towers is so extensive? We find out.
Most of the European manufacturers of the turbine towers have started outdoing each other in terms of their tower heights. Some of the popular players in this segment include Carter, Nordtank, Bonus, Vestas, Nordex, WindWorld, Tacke, Nedwind as well as WindMaster have turbine towers ranging till 50 meters as far as the height is concerned. In Germany, for instance, one company called Vestas has towers spanning 53 meters in height. One of the forerunners in the race is a company called Enercon that has wind turbines sitting on 63-meter towers. Back home in California, the San Gorgonio Pass has towers spanning a maximum of 49 meters in height.
Why the difference in heights?
Many experts who have studied the mechanisms of wind turbines opine that 60 meter height towers are appropriate for a place like Germany or deep forested regions inside Europe. However, as far as North America is concerned, there is no need for such tall towers. While experts may think tower height is not necessary, the NREL has touted a 50% performance improvement after installing wind turbines atop taller towers.
When are tall towers necessary?
The typical tower height for most wind turbines ranges between 27 meters to around 55 meters. Only in situations where the wind shear is high is a tall tower justified. Otherwise, the regular height towers do just fine. If the tower height is twice the usual measurement, it can enhance the wind’s power capacity by as much as 45%. In America, one of the very first states to test the efficiency of these tall towers is going to be Minnesota. The Minnesota Department of Public Service is trying to raise funds for constructing several anemometry towers that will be taller than usual heights. These will serve the purpose of gauging wind shear till a height of 60 meters from the ground levels. It will also provide concrete evidence as to whether wind turbines placed on taller towers do have production benefits.
Britain does not need tall towers
Experts have found that strong winds blow at heights of just 40 meters in Britain. Hence, there is no need to place wind turbines over very tall towers in this part of the world. In places like the Wales, the government is in fact planning to shorten its existing towers. The obtrusive nature of these towers below wind turbines makes the landscape seem harsher than usual while also inconveniencing people.
Aesthetics Vs. Performance
One other aspect that experts of wind turbines concur on is the aesthetic appeal of these towers. In order to help aircraft easily locate these high towers, these will be marked with bold colors and strobe lights. However, if every tower had such markings it would seriously hamper the beauty of the landscape. Hence, a balance needs to be in place between performance upgrades and aesthetic sensibilities.