Before building a community wind project, extensive research must be done to assess the area’s wind energy resource and to determine how financially practical the project will be. Because wind resource assessment determines the feasibility of the project, it is one of the most important steps developers must take before beginning project development. The research compiled in this stage is also necessary to acquire appropriate financing from lenders by proving to them that the project is economically viable in this regard.

Wind assessment is completed in several different phases. The first is an initial assessment, which includes researching existing data about the site and its weather. State wind resource maps, weather measurement sites, and other nearby wind resource data help make rough projections about the financial feasibility of a project. State wind resource maps can provide developers with a good idea of the wind potential in the area by determining what wind class the site would fall under. For example, a class three site provides marginal wind farm productivity, class four is promising, and class five is excellent.

Later, additional information about the site is gathered and researchers make use of wind direction vanes, data loggers, and meteorological towers. The data collected during this stage is compared to pre-existing information from the last ten years or earlier. This comparison helps determine whether the information collected represents a low, medium, or high wind year, which in turn allows for more accurate, long-term production estimates. National Wind Assessments, the wind resource analysis division of National Wind, offers a comprehensive wind resource analysis package which includes on-site meteorological (met) tower installation. National Wind Assessments sells and installs NRG’s 60 meter met towers and Composite Tower Solutions 80 meter met tower.

On-site meteorological towers measure wind speeds, wind direction, and other information about the air such as relative humidity and temperature, which helps determine the optimal placement of wind turbines. A turbine layout for the wind farm is then created based on the wind data collected.

A project’s estimated energy production and financial performance, calculated from this on-site data, must be acceptable to a bank that is lending money to the project to be considered “bankable” – an important factor in getting the project started. “Bankable” means a project that can provide enough wind energy to generate revenue and pay off its debt. Developers must be able to prove this to lenders in order to receive funding for the initial cost of installing a wind turbine.

Additionally, annual energy production for worst and best case scenarios and a projected cash flow model help make sure that projections are reasonably accurate, allowing the project to pay its debt.

The quality of research conducted in assessing the wind resource will ultimately affect the decisions of lenders and investors to participate in the project. Obviously, the larger the project, the more expansive assessment efforts must be. Without gathering effective and convincing data at this stage, it will be difficult for a project to receive proper funding to begin development.