Design Verification and Post-construction Feasibility Reassessment of Naubise Khola Micro Hydropower of Nepal

Abstract

Micro Hydropower (MHP) systems, generating up to 100 kW, are a vital solution for rural electrification in Nepal given the country's favorable topography and hydrology. This study evaluates the technical, economic, environmental, and social feasibility of the Naubise Khola Micro Hydropower Project located in Dhading district, Nepal. Field survey data indicate a design discharge of 45.738 l/s, a gross head of 164.6 m and a net head of 159.44 m after accounting for pipe friction and minor losses. Civil structures intake, canal, forebay, trash rack, spillway and penstock were re-analyzed and sized using standard hydropower design formulas, and a single-jet Pelton turbine was selected based on the available head and flow. Financial appraisal using a 6% discount rate over a 15-year plant life yields a Net Present Value of NPR 1,733,182, a Benefit-Cost Ratio of 1.16-1.29, and a simple payback period of approximately 8.4 years (10.7 years discounted). The results confirm that the project is technically sound, economically viable, and environmentally sustainable, though it currently suffers from an absent weir, deteriorated wooden transmission poles, and inadequate maintenance. Design and management recommendations are proposed to improve performance and to guide similar rural micro-hydropower developments.