## 2 Materials and Methods  
In general, based on the experience gained in this research project, the methodology and phases of wind resource assessment studies follow the flowchart of Figure 2, whereas the specific data processing method follows the flowchart presented in [8]. As electricity supply is essential for modern human activities and that wind energy is an increasingly developed alternative worldwide, wind resource assessment is crucial for testing the feasibility of this type of initiative in a specific location. For this purpose, the first step should be to determine whether wind resource assessment studies have already been performed at the site; otherwise, a study with a minimum duration of one year must be conducted. Figure 2: Methodology for studies on wind resource assessment. Whether a study is performed depends on several factors. The economic factor may be the most important because it determines not only whether the study is feasible as well as its magnitude, i.e., its duration, number of anemometer towers to be installed, tower characteristics, and equipment availability [9]. Another key issue to consider is technical and legal feasibility, i.e., whether a site's conditions make it possible to build and transport a tower, obtaining landowners' permission to erect a tower and legal requirements for its installation, such as municipal and civil aviation permits. After ensuring the availability of economic resources, important decisions are required regarding aspects, such as purchasing a prefabricated tower or constructing a tower from scratch. The former alternative is typically expensive, therefore leaving the option to design and build the tower from scratch. In both cases, experienced staff are required. Some system component (sensors and data loggers) options for wind resource assessment are available on the market. Their selection depends on technical characteristics, costs, availability, and warranties, among other factors. In addition to storing records on memory cards, data loggers can send data by email, as long as they have access to the Internet. After installing the tower and initiating the devices, the data logger must be tested to assess whether the data from all installed instruments are recorded and whether the values recorded are within the expected range or abnormal, possibly due to equipment failure or installation problems. Frequent equipment failures are often due to improper wind vane installation or data logger programming or battery discharge. The following measures aim to avoid these setbacks: accurately programming the data logger before installing the device, installing a solar panel large enough to prevent battery discharge, and periodically visiting the tower site to test the conditions of the entire system. After a year of measurements or when a report must be submitted, the data are processed. Thus, depending on the objectives and availability of financial resources, different tools may be used to process information from the data loggers, ranging from desktop applications such as Excel or MATLAB, which are easily accessible programs, to software such as WAsP, Windographer, and windPRO. For this study, an anemometer tower was installed at coordinates 2\({}^{\circ}\)43'58.06\" south by 80\({}^{\circ}\)11'56.97\" west (see Figure 3). On the tower, wind vanes were installed at 40 and 20 m, in addition to a thermometer, a barometer, and a relative humidity sensor. All instruments used, including the data logger, were purchased from NRG Systems [9]. All equipment and respective costs are outlined in Table 2, and the design of the tower is presented in Figure 4.  
Figure 3: Location of the anemometric tower on Puná island. Source: [3]. \begin{table}
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Figure 4: Details of design and assembly of the anemometer tower. The project requires not only the approval and resources of the sponsoring entities but also the permission of the landowners of the tower site.