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Wind energy potential in Ethiopia is estimated to be enormous due to local peculiar landscape situations. However, the country started to utilize the potential only very recently. One of the reasons for low utilization of wind energy in Ethiopia is the absence of reliable and accurate wind energy resource data. Development of reliable and accurate wind atlas helps to identify candidate sites for wind energy applications and facilitates the planning and implementation of wind energy projects. This paper presents wind energy data analysis and wind atlas of Geba catchment in North Ethiopia. The work reported in this paper is based on wind data collected over a period of one year from measuring masts in six different sites in Tigray Ethiopia. The data was analyzed using various statistical software to evaluate the wind energy potential of the area. Average wind speed and power density, distribution of the wind prevailing direction, turbulence intensity and wind shear profile of each site were determined. Wind Atlas Analysis and Application Programme (WAsP) was used to generate the wind atlas of the area and to develop the wind speed and power density maps. The data analysis indicates that the average wind speed at 10 m above ground level (a.g.l.) varies from 3.7 m/s to 6.64 m/s. The mean power density at 10 m a.g.l varies from 64 W/m2 to 301 W/m2. The prevailing wind directions are East and South East directions. The wind resource map developed by WAsP at 50 m indicated that the catchment has good wind power potential having mean wind speed and power density of 6.5 m/s and 288 W/m2, respectively.

The paper presents economic value of the design and manufacturing of essential oil production plant as a strategy for rural poverty alleviation in rural Ethiopia. The level of technology for small scale essential oil industry is characterized for rural community in Ethiopia. The adaptation of oil distillation technology for essential oil production is proposed for small scale industrial entrepreneur. Steam distillation method is selected considering the constraints to meet the socio-economic level of the rural community. The distillation plant has been modelled based on local resources and the first prototype has been manufactured and tested. The study showed that the small scale manufacturing industry in the country do not have the capacity to manufacture the complete distillation plant system with the required precision for standard quality of oil at affordable cost. Thus, the design and the experiment in the use of a prototype small size distillation unit showed that the technology is appropriate for essential oil distillation with low cost and minimal decrease in oil quality.

A wind pump prototype with 3.6 m rotor diameter, 19 m hub height above ground and 0.22 mm reciprocating pump stroke has been developed at the Department of Mechanical Engineering, Mekelle University. The prototype was designed and manufactured locally. Theoretical model based on combined efficiency of the rotor and the reciprocating pump was used to estimate the performance of the wind pump. One year wind speed data collected at 10 m height was extrapolated to the wind pump hub height using wind shear coefficient. The model assumed balanced rotor power and reciprocating pump, hence did not consider the effect of pump size. The theoretical model estimated the average daily discharge to be around 50 m 3 and 30 m 3 at 8 m and 12 m head, respectively. The prototype was tested with the same pump stroke but two different size pumps at two different heads. The pumps were with internal diameter of 55 and 70 mm and the test heads were at 8 and 12 m. Measurement of the flow rate, rotational speed and wind speed were made every 10 minutes during the test period. The data collected were analyzed to find the performance of the wind pump at the two test heads and two pump sizes. The flow rate data was plotted against binned wind speed data to determine the linear fit function. The linear fit function was then used to estimate the flow rate at any wind speed. With the 55 mm pump the measured average daily discharge was 20 and 19 m 3 at 8 m and 12 m head, respectively. With the 70 mm pump the measured average daily discharge was 41 m 3 and 30 m 3 at 8 m and 12 m head, respectively.