11. Wind as a Promising Alternative Energy Source in Ethiopia: Feasibility Analysis for Wind Farm Establishment and Investigation of Wind Energy Potential in the Upper Blue Nile River Basin

Ethiopia has an abundance of renewable energy resources, such as hydro, wind, geothermal, solar, and biomass. Access to sustainable energy services, on the other hand, is a major challenge for its people. The country is one of the 20 most impoverished countries in terms of clean energy access, with approximately 46% of the population without electricity. Ethiopia's government is focused on utilizing the country’s renewable energy resources. Hydropower is the primary renewable energy source that has been identified for this purpose. The Upper Blue Nile Basin (UBNB) is one of Ethiopia's 12 river basins with massive hydropower potential. It accounts for a significant portion of the country’s current electricity consumption. As hydropower is rainfall dependent, its long-term viability, under climate change, is highly uncertain in the future. Hence, there is a need to focus on diversifying renewable energy sources in addition to hydropower in the UBNB. The goal of this study is to investigate the suitability of wind farms in the UBNB using a multicriteria decision method as well as geographic information system and to determine the energy potential of suitable areas. Wind speed, slope, land use/land cover, distances from grids, roads, urban and protected areas were considered when determining suitable wind farms. Of the total area of the basin, only 1,498.69 km² (approximately 1% of the basin) was found to be highly suitable. Wind speed data from ten automatic weather station (AWS) sites at 15-min intervals were obtained from the National Meteorology Institute of Ethiopia (NMIE) for the purpose of estimating wind power potential over a four-year period (2017–2020). After performing vigorous quality control checks for internal consistency and technical wind sensor problems, the AWS wind speed data were analyzed using Microsoft Excel and MATLAB software. The highest wind power density was recorded at Wogeltena and Gatira, with wind power densities of 227.56 and 216.50 W/m², respectively, at a turbine height of 50 m. There is a noticeable seasonal difference in wind power density production. Power densities were higher during the dry and short rainy seasons than during the wet season. As a result, it is reasonable to consider wind as a viable supplement to hydropower in the UBNB. The most promising sites are in the northeastern parts of the study area. As a result, these areas may be considered viable for grid-connected and stand-alone wind energy applications. However, most of the wind speed data in this study had short durations and were insufficient for estimating wind energy potential at large scales. Furthermore, the meteorological stations were primarily installed for weather forecasting purposes, and their location might not be optimal for wind energy purposes. Therefore, future research should concentrate on identifying optimal wind energy-producing areas in the region. Furthermore, different wind speed measuring tools, such as taller wind masts than the AWS wind speeds, are recommended for further wind energy potential investigations.