Wind PowerWind Power Fundamentals Presented by: Alex Kalmikov and Katherine Dykes With contributions from: Kathy Araujo PhD Candidates, MIT Mechanical Engineering, Engineering Systems and Ub Pl iUrban Planning MIT Wind Energy Group & Renewable Energy Projects in ActionRenewable Energy Projects in Action Email: wind@mit.edu. One is the density of the air. Swept Area and Rated Power. • Air Density • Determining Estimates of Wind Power Density (WPD) and Wind Power Classes This calculator extrapolates the wind speed to a certain height by using the power law. wind turbine to calculate the total power in the wind that hits your turbine. 3. What is the The power into the turbine blads is a function of the wind speed to the 3rd power (V times V times V), air density, and swept area of the turbine blades. Understanding Coefficient of Power (Cp) and Betz Limit The coefficient of power of a wind turbine is a measurement of how efficiently the wind turbine converts the energy in the ... the air density is about 1.23 kilograms per meter cubed. (a)'Vertical extrapolation of wind speed based on the 1/7 power law. The wind profile power law relationship is : = where is the wind speed (in metres per second) at height (in metres), and is the known wind speed at a reference height .The exponent is an empirically derived coefficient that varies dependent upon the stability of the atmosphere.For neutral stability conditions, is approximately 1/7, or 0.143. Wind power capacity = wind power density X surface area of windmill X efficiency of windmill. Remember the Power In The Wind Equation: 3 P = Power (Watts) ρ = Air Density (about 1.225 kg/m3 at sea level) A = Swept Area of Blades (m2) V = Velocity of the wind By doing this calculation, you can see the total energy potential in a given area of wind. In this case, energy, flowing with the air with density through an imaginary surface with area with the speed during the time is . A typical block in Manhattan consumes energy at a rate of over 1,000 kWh per square metre each year, a power density of over 100 W/m 2.This is almost two orders of magnitude greater than the power density of wind power, and obviously you could not plaster Manhattan in wind turbines. Wind power or wind energy is the use of wind to provide the mechanical power through wind turbines to turn electric generators and traditionally to do other work, like milling or pumping. This type of energy is called the kinetic energy and is a function of fluid’s mass and velocity, given by (2.2) K E = 1 2 ⋅ m ⋅ U 2. Wind power is the rate of kinetic energy flow. Wind energy by definition is the energy content of air flow due to its motion. parameters & determining the available power density. (b) Mean wind speed is based on Rayleigh speed distribution of equivalent mean wind power density. Formula: Wind Power = ( 0.5 * D * E * V * A 3) Where, D - Density E - Energy Efficiency V - Wind Velocity A - Windmill Area Related Calculator: At 15,000 feet it is typically 57 percent of its density at sea level and at 30,000 feet it is typically about 31 percent of its density at sea level. Average speeds in the table are based on the so-called Rayleigh speed distribution and are given for the sea level. The second approach is the power law. Remember the Power In The Wind Equation: 3 P = Power (Watts) ρ = Air Density (about 1.225 kg/m3 at sea level) A = Swept Area of Blades (m2) V = Velocity of the wind By doing this calculation, you can see the total energy potential in a given area of wind. meter = .0006 V 3
The wind power formula is given in terms of velocity of wind, area of the blade and air density.