A practical and economic method for estimating wind characteristics at potential wind energy conversion sites

In order to assess the economic viability of installing a wind energy conversion system (WECS) at a site; it is necessary to know the wind characteristics at that site. Since it is usually impractical to measure wind at all potential sites over a suitably long period of time, it is necessary to develop a methodology that can provide accurate estimates of wind economically at potential WECS sites from data that are already available. A physically based, three-dimensional model has been developed that incorporates the effect of underlying terrain and uses available, conventional wind information from selected nearby weather stations. This model—called COMPLEX—is essentially an objective analysis computer program that interpolates values of wind from observations at irregularly spaced stations. The required statistical wind characteristics are estimated from the synthesized hourly winds, which are obtained by using the COMPLEX model; the model is used in conjunction with a method for reducing the number of variables while still retaining most of the information of the original data set. This involves eigenvectors of the covariance matrix of the original data set. The linear characteristics of the COMPLEX model have been used to obtain solutions directly for only the few eigenvectors of the input for any arbitrary set of observations from linear combinations of those solutions. We describe here an example of the application of the method to a potential wind energy conversion site at Boone, North Carolina.