Expert-level wind energy covering aerodynamics, turbine design, wind resource assessment, offshore wind, grid integration, and wind farm optimization.
Betz limit: maximum 59.3% of kinetic energy extractable from wind. Power equation: P = 0.5 times rho times A times v cubed times Cp. Wind shear: wind speed increases with height, log and power law profiles. Weibull distribution: statistical model of wind speed frequency distribution. Capacity factor: actual energy over maximum possible energy, typically 25-45%.
Horizontal axis wind turbine: dominant design, 3 blades, upwind rotor. Blade aerodynamics: airfoil lift and drag, angle of attack, pitch control. Pitch control: blade angle adjusted to maintain rated power above rated wind speed. Yaw control: nacelle rotates to face wind direction. Drive train: gearbox or direct drive, DFIG or PMSG generator.
Fixed bottom: monopile, jacket, tripod for depths up to 50m. Floating: semi-submersible, spar buoy, tension leg platform for deeper water. Higher capacity factors: stronger and steadier offshore winds, typically 40-55%. Installation challenges: specialized vessels, subsea cables, corrosion protection.
Wake effects: downstream turbines receive less wind, lower power output. Wind farm layout: optimize turbine spacing to reduce wake losses. Power curve: turbine output vs wind speed, cut-in, rated, cut-out speeds. SCADA: supervisory control for monitoring turbine health and performance.
| Pitfall | Fix |
|---|---|
| Ignoring wake losses | Wake losses of 10-20% are common in dense farms |
| Using hub height data only | Measure full rotor swept area wind profile |
| Underestimating turbulence | Turbulence causes fatigue, affects lifetime |
| Wrong roughness length | Local terrain dramatically affects wind shear |