PERFORMANCE EVALUATION OF MICRO HYDROPOWER SCHMES ON UNGAUGED STREAM THE CASE OF BASHIRO-GUTE – (ERERTI RIVER)

Abstract

This study was aimed to Performance Evaluation of Micro Hydropower Schemes on Ungauged Stream the Case of Bashiro-Gute – (Ererti River). The methodology that was applied in this analysis was quantitative research approach and using GIS software. Specifically, to assess the current status of the scheme, the factors behind the failure and estimating the potential and designing the proposed structures. The stakeholder interview, field observation, document review and secondary data (30-year simulated stream flow) were collected and the analysis was conducted. The physical observation has shown that the existing condition of the components especially the diversion weir and power canal of the Micro hydropower plants was broken and collapsed and do not provide the functions. The causes of failure of the plant were lack of technical feasibility study (structural instability), public participation and consultation shortage on the plant development, lack sense of ownership among the community and stakeholders of the project to protect and manage the plant. The plant development has not followed the scientific design method. The potential assessment of the Ererti River has indicated that 74.9kw, 86.4kw, and 153.6kw actual power could be generated from 0.4 m3 ⁄s, 0.5 m3 ⁄s, and 0.8 m3 ⁄s discharge design at 100%, 95% and 50% exceedance time respectively. For average potential hydropower which was 0.8 m 3 /s, the proposed crest dimension was top width 0.8m, bottom width 2.3m, and height 2.65m. The power canal that proposed was width= 0.8m, depth=0.4m with the bed slop of 1:2, wetted perimeter =0.2m and bed slop 1 to 0.01m with 1m head loss. The 300mm diameter of penstock is calculated with the head loss of 0.02m as suitable to transfer the water to the turbine. The net head available to produce the power from 50% exceedance time discharge was 27. 98m.The measured weir crest dimension was top width 0.9m, bottom width 2.0m, and height 2.01m.and the power canal bottom width width= 1m, depth=1.5m with the bed slop 1 to 0.01m and the 300mm diameter of penstock is measured