An Application of the WAsP Program in Complex,Forested Terrain as Part of a Wind Farm Feasibility Study

Abstract

This paper describes an application of the WAsP program in complex, forested terrain in the central North Island of New Zealand. The work was carried out as part of a research project that investigated the viability of developing a wind farm for the Kinleith pulp and paper mill. Subsequent to an outline of the limitations of the WAsP program, the study area, its representation in WAsP through digital terrain data, and the wind data collection at three sites in the Kinleith Forest are described. A comparison of WAsP predictions with field measurements is found to qualitatively confirm the RIX concept. For the study area an adjusted relationship between site ruggedness and prediction error is derived. Studying a potential wind farm located along a ridgeline in the forest estate, the size of forest clearings and the growth of trees over the wind farm lifetime are considered in view of expected annual energy yields.

Keywords

WAsP wind resource complex terrain ruggedness index (RIX)forest effects frontal area index

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