The streamlined site assessment methodology: A new approach for wind energy site assessment
This research develops superior approaches to the traditional site assessment process, as well as novel strategies that offer a distinct advantage over the traditional process. Two major contributions are presented: new analysis approaches for site assessment, and new technical approaches to wind resource monitoring.
Two new analysis approaches for wind energy site assessment are developed. The first is a method for site assessment uncertainty analysis. Analytical expressions for the sensitivity factors of the Weibull parameters are developed, which yield exact values for any combination of wind resource, power curve, and energy losses. This enables better determination of the uncertainty in the annual energy production estimate. The second approach is a decision making strategy to determine whether or not to stop measuring the wind resource at any point in the process. In contrast, in the standard approach, the wind resource is almost always measured for a full year, which can be inefficient in many cases. The results show that this approach is just as accurate as measuring for a year, but saves significant time and money.
Two new technical approaches for measuring the wind resource are developed. The first measures multiple sites in a year using one ground-based device, which is brought back and forth between sites, resulting in two discontinuous measured data sets, each distributed over the year. The accuracy and uncertainty of the predictions of the wind resource are equivalent to those using a full year of measured data. The second new technical approach can improve shear extrapolation. It relies on short-term data from a ground-based device at a site where a met tower is installed for a year. The short-term data are used to correct the year-long shear parameter. The results show substantial improvements in the accuracy and uncertainty of shear predictions.
These new analysis approaches and technical monitoring strategies are unified into a comprehensive "Streamlined Site Assessment Methodology." It provides a flexible, unified approach for executing the site assessment process in which the specific priorities and constraints of the project dictate the resulting approach. This methodology can drastically alter and improve site assessment.