Water Mill cum Hydro Electric


Lima Mill used for grinding 

                                                                                                                     Photo Source:angelfire.com

                                                Water mill is one of the traditional kind of grinding wheel that uses wheel or turbine to drive a mechanical process for various end use such as flour grinding,lumber or textile production.This type of technology is applicable in hill areas where there is enough head for running turbine. The water diverted from river or canal provides enough kinetic energy to drive wheel or turbine via head race channel or pipe.The force of the water’s movement drives the blades of a wheel or turbine, which in turn rotates an axle that drives the mill’s other machinery.

                                          Water leaving the wheel or turbine is drained through a tail race, but this channel may also be the head race of yet another wheel, turbine or mill.This kinda of water mill is suitable in hilly and Himalayan region of Nepal where enough head is available.Not only for milling but it can generate electricity which can empower local community which can contribute for decreasing load on central load distribution.

Water Mill cum Micro hydro in Aghakhola, Palpa

                           This is good example of use of appropriate technology helping people to live under light. The micro-hydro generates electricity to operate mill services for customer and provides power in night to local resident in vicinity. 


Hydro Power in Nepal


              ‘Hydro’ or water power refers to the energy of the movement of water being converted into electricity. The general process is power generation by use of water. Hydroelectricity is one of the most mature forms of renewable energy, providing 19% of the world’s electricity consumption from both large and small power plants. The most common type of hydropower uses dam or reservoir for water holding still there are run-off type of project too. Hydro electric power is based on the principle of using falling water to spin a shaft connected to an electric generator. The greater the fall of water, the more power it has to spin. The greater the quantity of water, the greater the number and size of the shafts that may spun and the greater the electricity output. The amount of power produced depends upon following factors:

  1. The Flow [quantity of water passing]

  2. The Head available [Vertical distance of water can be made fall]

Advantages of Hydropower

  1. Non- polluting, clean and environment friendly

  2. A renewable source of energy

  3. Cost of generation, operation and maintenance is lower than the other sources of energy

  4. Ability to start and stop quickly and immediate load acceptance/rejection makes it suitable to meet peak demand and for enhancing system reliability and stability

  5. Long operating life

  6. Cost of generation is free from inflationary effects after the initial installation

  7. Storage based hydro schemes provide benefits of flood control, irrigation, drinking water supply, navigation, recreation, tourism and aquaculture, and

  8. Opening of avenues for development of remote and backward areas

Hydro Power in Nepal

          Hydropower so far has been only source of power generation of our country. The growing need of power is increasing day by day while power generation is lagging far behind than demand margin. Nepal is blessed with immense potentialities of hydropower generation. Our country ranks second in water resources after Brazil and posses large potentialities for hydropower generation. Nepal is gifted with economically exploitable hydro-power potential to the level of 42000 MW of installed capacity out of total hydro potential of 83000 MW. Nepal’s immense hydropower potential needs to exploit in broadening the market that is developing in the domestic and regional areas.

         Despite the immense hydropower potential in Nepal, only 40 % of its population have access to electricity including 33 % from NEA grid and 7 % from other alternative source of energy( NPC 10th Plan).

Reasons For Development of Hydro Power in Nepal

Minimal contribution to global warming: Hydropower generation does not generate significant quantities of CO2. Some CO2 is generated during construction, but this is minor and comparable to what would be required to construct any power generation facility.

Clean:Hydropower generation does not generate air or water pollution, although there is a potential  for water quality impacts in and downstream of larger reservoirs.

Security:Hydropower development requires large capital outlays. But, once built, they are not dependent on imported fuels and the security issues associated with being a landlocked country.

Stability: Cost of development, construction and operation can be well documented and predicted. Once built, the fuel is free and power generation costs are not subject to fluctuations in fuel or transportation costs. Many hydro projects I am working on are over 50 years old, and several are over 100 years old. Under the right conditions, hydropower facilities can run at low operational costs for 50 years or more providing low-cost, clean electric power.

Technological transfer and self-sufficiency: Within Nepal there is growing institutional knowledge and capacity regarding this sector. Enough projects have proceeded in Nepal to enable Nepalese nationals to complete much of the engineering, environmental and social work elements and analysis. In addition, there is now a large cadre of Nepalese construction workers who have worked with international construction companies and have had critical safety and technical training. As a result, Nepal has a trained work-force ready to work on large construction projects.

Power exports:Nepal has the opportunity to export power, thereby contributing to balance of trade   and providing needed revenues for the general economic and social progress.

Potential: Nepal has vast hydropower generation potential that has only lightly been tapped. 

Poverty alleviation:Hydropower development, in association with linked development projects, can contribute to poverty alleviation and improved living conditions and health for communities in the project area as well as nationwide.