Review of low head turbines system of Nepal for rural electrification

Small or micro hydro power generation is a promising renewable energy source that has received significant attention because of its capacity to generate green energy ranging from few watts up to hundreds of kilowatts. Small, low head hydropower plants are applicable in remote areas where grid extension is difficult due to geographical terrain. Micro hydro generators do not require the large cost of civil works for conventional hydropower and do not require the cost and environmental impacts of constructing a large dam and diversion structure. Recently there has been increasing interest in low head small hydro turbines by researchers and stakeholders who are working for rural electrification of off-grid communities in Nepal. This study discusses research and practice using various low head water micro hydro generators, including Improved Water Mills, Pico Hydro Generators, Gravitational Water Vortex Power Plants and Archimedes Screws, in Nepal. Major innovations with these systems by researchers working in Nepal are reviewed, and recent steps towards commercialization are discussed. The various technical and economic parameters of those systems are compared and evaluated. This information is essential for researchers and stakeholders to optimally select a suitable turbine according to site and economic conditions.