Choosing a Turbine Siting Location

Hello, I’m relatively new to this field and have been mostly working in turbulence modeling. I gave a newbie question (hopefully this is the right place for it).

For a turbine (say TurbA) with a given rated wind speed (say 10m/s), how does one decide on suitability of the place where you would want to cite it? I guess, I could figure out a PDF for wind speed at a certain place, and then compute some sort of a weighted average based for expected annual energy output. I’ve heard some people use the term Annual Energy Production (AEP), which is I think is just a weighted average to get an expected power.

But, I am not sure about how one applies this realistically. So, would placing TurbA (with a rated wind speed of 10m/s) at a location with say an average annual wind speed 10m/s be the too conservative? In other words, would are you more likely to put it in a place with average wind speed of 15m/s, so that you would expect a higher capacity factor? What is the typical industry standard for this?

My primary reason for asking about this, is that I am trying to physically quantify the annual loss due to wakes for a sample turbine (WindPact 1.5MW) using a physics based model. But, in order to come up with actual numbers, I would like to model the problem at a certain real location. Was the WindPact 1.5MW turbine designed for a particular location?

thanks,

aditya

Dear Aditya,

Rather than designing a wind turbine for a given site, wind turbines are usually designed to a given IEC wind class, which is based on a reference wind speed and turbulence category. The IEC wind classes assume that the highest 10-minute average wind speed in 50 years is equal to five times the annual average wind speed. A given turbine will only be selected for a given site if the local site conditions are not more severe than the IEC wind class the turbine was designed for. The WindPACT 1.5-MW turbine was designed for IEC class II-A conditions (Vref = 42.5 m/s; Iref = 0.16).

Turbine selection is more related to cost of energy than capacity factor, altough both are related. But it cannot be assumed that higher capacity factor is always better – a turbine with a very large rotor and a very small generator could have nearly 100% capacity factor, but this is likely not cost-effective.

Typically the rated wind speed of a turbine is higher than the annual average wind speed. There are very few sites in the world with annual average wind speeds above 10 m/s.

Best regards,

Hi Jason, thanks a lot for your quick response.