Wind Turbine Blades



Wind Turbine Blades

Introduction

The wind energy industry is one of the fastest-growing fibre business reinforced plastics in the world. Production challenges are compounded as large scale operations of wind turbines continues to increase at a rapid pace. Blades, among the most complex parts to mould, now exceed 80 m in length and are getting longer. Currently wind turbines generate less than 2% of the total electric energy in the US. The DOE aims to produce 20% of electric energy used in the US from wind in the next few decades. This represents more than a tenfold increase in production, and it will require extensive investments as well as research and development in wind turbines, energy storage systems and electric grid integration techniques. These machines have economic incentives, as well as reducing the US's energy dependence on fossil fuels which both pollutes the atmosphere, and are neither renewable nor sustainable. Sustainability issues arise because as societies grow, there is a corresponding increase in energy consumption. In addition, the supply of fossil fuels is subject to other external factors such as politics and other world events, thus creating an issue of national security. In order to meet this goal of energy independence, it is important to produce more efficient turbines which can compete with other forms of energy production systems, and that is why this research is necessary. Therefore, all the issues related to epoxy composite materials in wind turbine blades will be discussed in detail.

History of Wind Turbine Blades

Attempts to produce energy from the wind were first made in 1891 by Poul La Cour in Denmark. He first built an experimental wind turbine to utilize wind power for the generation of electricity. In 1908 Lykkegard Company started the industrial utilization of his developments and built various sized wind turbines with power outputs ranging between 10 to 30 kW. This was a departing point in commercializing wind turbines. Since the beginning of the nineteenth century engineers and scientists have been working on developing wind turbines that could be competitive with other energy sources in power generation. Modern wind turbines generate power efficiently and reliably in a range between 10kW (small land base wind turbines) to 6 MW (large scale off-shore wind turbines) using innovative drive and control technology. To get more power output, year after year wind turbines tend to grow in size (Agarwal, 2008, 51).

As can be seen, for the past decade the power production of wind turbines has increased by two-fold and rotor diameter has increased by about 50%. The reason for increasing single wind turbine rotor diameter rather than increasing the number of units in wind farm is related to expenses associated with installation, electrical interconnection, maintenance and access per installed kW of wind farm capacity. These expenses are lowered by increasing unit capacity in a wind farm. Additionally, the power production from single wind turbine, which depends on rotor diameter, will increase. Wind power is the fastest growing energy resource with an annual growth ...