Editorial: Towards Innovation in Next Generation of Wind Turbine Rotor Design

The development of renewable energy is an inevitable response to the dual challenges of the energy crisis and global warming. In many countries, wind energy has become the most cost effective renewable energy relative to other energy sources. In order to reduce the cost of electricity, modern wind turbines are increasing in rotor size and unit power. The big wind turbines currently in the market are reaching 15 MW rated power and will be possibly increased to 20 MW in a few years. In such a scenario, the continued development in wind energy has led to large rotors that are much lighter and cheaper per kilowatt than before. The main innovations include higher tip speed, higher lift and thicker airfoils, resulting in more slender and lighter blades. In the meanwhile, the coupled effects of aeroelastic and aeroacoustic behaviour and modelling have become the key research challenges. Therefore, research in many aspects of wind energy innovation is important, such that the overall objectives of low cost of energy, high system reliability and environmental-friendliness can be achieved. Several rotor design concepts have emerged to satisfy the up-scale trend, but a crucial problem is managing the large inertial loads and aeroelastic response while retaining high aerodynamic efficiency. Further utilizations of wind energy research meet the critical challenge to continuously grow in size and continuously decrease in price per kilowatt.