The higher the rotational speed, the louder the sound. Read more in the guided tour page on designing for low aerodynamic noise . Rotor blade manufacturers take extreme care to ensure a smooth surface which is important to avoid pure tones. Likewise, manufacturers who install wind turbines take great care to ensure that the rotor blades are not damaged when a wind turbine is being installed. Read more in the guided tour section on sound from wind turbines .
Wind turbines use only the energy from the moving air to generate electricity.
A modern 1,000 kW wind turbine in an average location will annually displace 2,000 tonnes of carbon dioxide from other electricity sources, i.e. usually coal fired power stations. In other words, on average it takes only two to three months for a wind turbine to recover all the energy required to build and operate it. Read more in the guided tour section on the energy payback period for wind turbines 3. Abundant Wind resources are plentiful. Wind will not run out.