Wind farm Site Assessment

                             


With the large scale development of wind farm sites in new areas involving huge investments including foreign funds, investors and lenders want to be doubly sure about the return on investment. In fact, their decision on investment is by and large based on site assessment by a reputed and reliable agency. This assessment is essential even though a detailed project report has been prepared. It, therefore, makes sense to get this assessment done as early as possible after identification of a prospective site and  well before site selection and commencing the development. That said, it is never too late to get it done, to enhance the marketability of a site.

What are the major factors that determine the viability of a wind farm site? What makes a site lucrative to an investor and acceptable to a lender? The answer is simple and straightforward. Wind, power evacuation, accessibility and logistics are the  major issues that matter in the assessment of a site. Policy, tariff, land availability and environmental and social issues also have their impact on projects.

Wind resource assessment is done based on data collected over a long period of time. Data collected from met masts installed at the site is most important in accurate assessment. It is therefore important to visit the mast locations  and verify whether it is being done properly. A thorough check of the masts and instruments mounted on it by a trained and experienced technician is necessary. Adequacy of the masts in terms of numbers, height and of course, the  quality, calibration and positioning of sensors need to be examined.

Power evacuation is another important aspect. The location of sub station should be close to the wind farm. Are there any likely bottlenecks in the evacuation system? Is the wind farm layout compact enough to facilitate power evacuation with limited line length and consequently minimum transmission loss?From the turbine to the pooling station to the sub station the transmission system has to be examined. In fact, it is required to ensure minimum losses up to the metering point which may be at the sub station.

Good windy sites may be in remote areas and more often than not in hilly terrain. Accessibility to the site needs to be factored in such cases. It is all the more pertinent for transportation of tower parts, turbine (nacelle), blades and heavy cranes for erection of wind mills. With the higher capacity turbines having larger rotor diameters and higher towers, transportation becomes a critical issue. The roads that take you to the site may require improvements. From the ground level at hill bottom to the hill top you may have to construct new roads to reach the micro-sited turbine locations. Does the hill slope allow the road construction with adequate width, turning radius and acceptable gradient? The deployability at the hill top is also a matter of concern. Soil condition is yet another important factor which cannot be overlooked. Construction may not be feasible and economic on hard rocky surface. Vegetation in and around the turbine locations also has to be considered.

Environmental issues such as soil erosion, damage to vegetation and disturbance to wild life need to be considered. These apart, the local people should not suffer in any way due to the project, be it displacement of people, loss of farm land or disturbance due to rock blasting and construction. If unavoidable, compensatory provisions need to be considered.

Site assessment by an expert team which looks into various issues mentioned above will be of great value in decision making and taking the right steps during project execution. When such an assessment is done by an agency of international repute it adds value to the project proposal in terms of bankability. It will help in luring investment for the project from discerning lenders and investors.