Micro Hydro Development In Nepal
History of Micro-Hydro DevelopmentThe history of waterpower in Nepal begins with the traditional water mills or ghatta used for grinding flour. Nepal has over 6,000 rivers of length over 2 km. Therefore the total theoretical potential of micro-hydropower is very large. However, there are varieties of technologies already available or being developed, which come under the mini and micro hydropower category. The improved ghatta i.e. Multi-Purpose Power Unit (MPPU) also known as improved water mills (IWM) is an innovation on the traditional ghatta. This uses a metal runner to increase efficiency higher than that of traditional ghatta.
Turbine for milling purpose, accounts for more than 50 percent of the existing micro-hydro schemes in Nepal at present. These schemes are used to run a range of agro-processing machines such as rice huller, grinder, oil expeller and other end use applications.
In some cases, a small generator is added to an existing turbine mill to provide electric lighting in the evening to the communities close to the powerhouse.
A peltric unit consists of an induction generator with the runner of a pelton turbine hanging from its shaft. It is designed to operate under a head of 20-50 meters and flow up to 25 liters per second and is suitable for providing electric lighting to a few households.
A turbine installation that is established primarily to produce electricity and to serve agro-processing activities only as a secondary function is called a stand-alone micro-hydro power plant.
MicroHydroNepal_Opportunities and Challenges