ABSTRACT
Harvesting energy on a large scale is, without a doubt, one of the main challenges of this century. Future energy sustainability strongly depends on how the renewable energy problem is addressed in the next few decades. Considering only 13% of the Earth’s surface and using conventional onshore wind turbines (WTs), with 80 m towers, the estimated wind power that could be commercially viable is 72 TW. That is almost Žve times the global power consumption in all forms, which currently is about 15 TW on average. With a capacity that has tripled in the last 5 years, wind energy is the fastest growing energy source in the world. WTs are used to collect kinetic energy and to convert it into electricity. The average power output of a WT unit has increased signiŽcantly in the last few years. Most major manufacturers have developed large turbines that produce 1.5-3.5 MW of power, reaching even 5-6 MW per turbine in some remarkable cases. Grouped together to create wind farms, the global collective capacity generates 340 TWh of energy, equaling 2% of the global electricity consumption, with 200 GW of wind-powered generators worldwide by the end of 2010.
