Wind Turbine Energy Yield Calculation at a Given Site

[Ktulu]

Homework Statement

I need to find how much energy will be produced (at least approximately) at a site with the following characteristics (this is taken from the German Renewable Energy law):

“The reference site shall be a site determined by means of a Rayleigh distribution with a mean annual wind speed of 5.5 metres per second at a height of 30 metres above ground level, a logarithmic wind shear profile and a roughness length of 0.1 metres.”

Homework Equations

How can I find out how much energy can be produced at such a location? What other information do I need? I am especially interested in what Rayleigh distribution implies here, and how I can use this information

 

[jbsteele]

.The Attempt at a SolutionTo calculate the energy that can be produced at this location, you will need to first determine the wind power density at the site. This can be calculated using the following equation: P = 0.5*ρ*A*V3 where P is the wind power density in Watts per square metre (W/m2), ρ is the air density in kg/m3, A is the rotor swept area in m2, and V is the wind speed in m/s. Once you have determined the wind power density, you can then calculate the total energy produced by the turbine over a given period of time. For example, the annual energy production (AEP) can be calculated using the following equation: AEP = P * 8760 hours where 8760 hours is the number of hours in a year. The Rayleigh distribution implies that the wind speed at the site is distributed according to a normal distribution with a mean annual wind speed of 5.5 metres per second. This means that the wind speed is likely to vary around this value, and the total energy produced will depend on the average wind speed over the year.