The wind turbine, and its failure - Case Study Example

The Wind Turbine and Its Failure The Wind Turbine and Its Failure How the Wind Turbine Works Wind power (wind energy) is basically the generation of mechanical power or electricity from wind. A wind turbine converts kinetic energy of wind into mechanical power, which can be used to execute various tasks such as pounding cereals or pumping water from boreholes. Further, this mechanical power harnessed from the wind through the use of turbines can also be converted into electricity using a generator.

Though comparable to a fan, a wind turbine generates electricity using wind unlike a fan that needs electricity to generate air currents otherwise called wind. The wind sets in motion the turbine blades, which rotates a shaft connected to a generator that converts the mechanical energy fed to it into electricity. Despite its relative importance, especially in the present world where strategies are being focused on the production of clean energy to curb high levels of greenhouse gases in the atmosphere, the wind turbine also exhibits some failures.

Wind Turbine Failures Wind turbine failures can be categorized into two groups. The first failure is the hard-type failure, which includes the gearbox, electric generator and rotor failures. The second type is soft-type failures, which is basically control system failure (Steenbergen et al., 2013). The Blades Failure Blade failures can occur because of different reasons leading to the throwing of the entire blade or part of it from the wind turbine. Many failures of the wind turbine blade involve the structures linking the blade and the hub.

“At the blade root, the oscillating stresses are passed into the rotor hub and certain harmonics are passed through the shaft into the tower” (National Research Council (U.S.), Energy Engineering Board 1991, p. 27). Other failures relate to the steel connectors joining the main blade part and the bearing. Further blades failures are usually noted in “subassembly joint s in the main blade component and chord wise cracking of the blade shell” (National Research Council (U.S.), Energy Engineering Board 1991, p. 27). The fatigue and How It Gets Failed by the Weather and the Birds In most cases, structures loaded regularly often fail at lower loads than expected.

Wind turbines are subject to changing lift force from wind explosions, wind sheer yaw error as well as turmoil. The lifting wind acts in a flapwise bearing. The blades also have to contend with their own weights. This leads to reverse bending as the wind turbine’s blades rotate. Bad weather is also known to be detrimental to the life and efficient operation of wind turbines. Ice from frozen precipitation can lead to coating of the nacelle and turbine blades of the wind turbine making the shut-off mechanism ineffective.

Further, extreme wind power because of bad weather can lead to excessive vibration of the tower of the turbine, which can in turn lead to complete or partial failure of the blades causing great financial loss. Wind turbines are also known to be a threat to the life of birds. Birds often collide with turbines sited inappropriately and this can lead to reduction of bird population making the turbines ecological threat. When large birds collide with turbine blade, mechanical breakdown may occur, leading to failure of the affected wind turbine.

The Gearboxes Failure Wind turbine gearboxes are exposed to various problems, which result from faulty occurrences during their operation. Faulty incidents such as lubricating oil leaks leading to a fall in the level of oil or use of unauthorized type of oil can lead to inadequate lubrication and cooling. Consequently, some sections of the gearbox become over heated, which may lead to further damage. These damages in turn cause tooth breakage and consequently permanent failure of the gearbox (Hemami, 2012).

The gearbox of a wind turbine is usually associated with two major issues. First, the gearbox is not used to reduce speed as many applications exhibit. Second, the nature of wind subjects the wind turbine gearbox to regular and sudden shocks due to the variation in the power that it handles. “Such power fluctuations, which in turn translate to load variation on the teeth, is not a desirable situation for the gearbox” (Hemami, 2012, p. 199). As such, the chances of damage and failure of the wind turbine gearbox remains high.

Worse still, replacing a malfunctioning wind turbine gearbox is very costly owing to the fact that the operation is not carried on the ground (Hemami, 2012). An example of gearbox failure occurred in a wind farm in Canada in 2004. No PdM was used and the gearbox failure required a complete replacement, which cost more than $250,000 (Barber & Golbeck, n.d). Also, a severe weather with wind speed exceeding 100 Kph and freezing rain led to extreme tower vibration and coating of the nacelle and turbine blades with ice respectively leading to a complete loss of one turbine at Canadian Wind farm, 750kW turbines, age: 10 years (Barber & Golbeck, n.d). From these case studies, it remains clear that wind turbines can experience failures, which can prove very costly to repair or replace.

References Barber, S., & Golbeck, P. (n.d.). Wind Turbine Maintenance & Condition Monitoring. Retrieved on November 27, 2013, from http://www.wwindea.org/technology/ch03/en/3_4_3.html Hemami, A. (2012). Wind turbine technology. Clifton Park, NY: Cengage Learning. National Research Council (U.S.), Energy Engineering Board (1991). Assessment of research needs for wind turbine rotor materials technology. Washington, D.C.: National Academy Press. Steenbergen, R.D.J.M., van Gelder, P.H.A.J.M., Miraglia, S.

, & Vrouwenvelder, A.C.W.M. (2013). Safety, Reliability and Risk Analysis: Beyond the Horizon. London: Taylor & Francis Group.