Extreme Winds in Kuwait Including the Effect of Climate Change

Abstract

Wind turbines need to convert the kinetic energy of normal wind speed into electric power but the structure needs to withstand the wind loads exerted by the extreme wind speed on the mast and blades. Also high rise buildings around the world are designed for a wind speed whose probability of exceedence is 2% (Gomes and Vickery (1977), Milne (1992), Kristensen et al., (2000), Sacre (2002) and Miller (2003)). Recently, the State of Kuwait has approved construction of multistory buildings up to about 70 floors. For safe and optimal design of these high rise buildings, extreme wind speeds for different return periods and from different directions are essential. Wind data, measured at 10 m above the ground level at different locations can be used for the prediction of extreme wind speeds at that elevation. These unexpected high wind speed from different directions dictates the design of many structures like towers, high rise buildings, power transmission lines, devises for controlling the sand movements in desert areas, ship anchoring systems in ports and harbors, wind power plants on land and sea, chimneys etc. Also normal and extreme wind data is required for ground control and operation of aircrafts, planning for mitigating measures of life and properties during extreme winds, movements of dust etc. One of the factors for fixing the insurance premium for buildings, aircrafts, ships and tall towers by insurance companies is based on the safety and stability of these structures for extreme winds. The extreme wind speed, whose probability of occurrence is very rare, is also responsible for generating high waves in the seas, which dictates the design, operation and maintenance of all types of marine structures. How does one know the maximum wind speed which is expected at a specified location on the earth for a return period of 50 years or 100 years? This is a billion dollar question. The down to earth answer is Install anemometers and measure the wind speed for 50 years or 100 years. One cannot wait for 50 to 100 years to obtain the maximum wind speed for that such a large period. The procedure is to use the available and reliable past data and apply the extreme value statistical models to predict the expected wind speeds for certain return periods (Gumbel (1958), Miller (2003)). Most of the countries around the world have the code for design wind speed and wind zoning systems. As on today, Kuwait does not have a code for design wind speed. Wind speed and its directions have been measured in many places in Kuwait for certain projects (for example, Abdal et al., (1986), Ayyash and Al-Tukhaim (1986)). It is also reported that the hinterland areas of Kuwait has wind power potential of about 250 W/m2 which is appreciable (Ayyash and Al-