Mini-micro hydel power stations

Chapter 6 describes world technology scenario and technology available in India. The various manufactures, suppliers their capability to supply equipment for MMH plants is very important factor to note at all of them have collaboration with one or other leading manufactures in Europe or U.S.A. and therefore are having sufficient technical backup as and when needed most of the collaborations also envisage sharing of R & D experiences and also have some R & D set up to come up with solutions to problems of smaller dimensions. They all have design engineering facilities but prefer to supply one out of standard design available as the detailed design of standard sizes and facilities of manufacture for normal size are available and would save time and cost of equipment. Some of the manufacturer/supplier is described here.

We have also gone through the reply submitted by them against our questionnaire and their suggestions for cost reduction are being recorded here. Most of them are of the view that reasons for slow growth of new MMH power stations are financial and bureaucratic hurdles. In their opinion, growth is achieved by standardization of machines and by soft loan/subsidy from Govt. of India. Subsidy could be considered as a part of social up liftmen of that particular village. They have also informed the cost could be reduced with use of cheaper materials which are highly developed, like use of aluminium plant instead of SS fore runner. Some of them have indicated that new technology like use of vertical type turbine compared to S type turbine could reduce manpower to one operator per shift and thereby reduction of cost and civil works and operation and maintenance cost in due course of time so as to make the MMH power feasible. Use of hydro pulser at MMH system could be another way of the cost reduction although hydro pulser is based on old technology of hydro ram. It uses devices which can raise the water upto 15 times the original height of the water fall. The hydro pulser does not need any external energy but works continuously and automatically. It employs the force generated by the moment of water fall and inertia of the machine. It works without electricity or fuel and requires very little maintenance and can be used for generation of small current by connecting a water turbine and an ordinary alternator or a centrifugal pump in a reverse manner. The falls from 2-10 m. will be able supply installation capable of producing 50-100 k W of electricity. Therefore, these system could be promoted for micro generation system as they have a negligible operating cost.

The Chapter 7 describes experience of neighboring countries where enormous development has taken place in development of micro hydel power. We have described in detail the experience of China where. Full utilization of the scattered small hydro Power potential in combination with water utilization for other purposes is ensured by constructing power stations to meet local electricity demand. There are many stations, each covering certain areas, scattered throughout the country. A local network is formed and connected to the government run grid. This should meet demand in rural areas for electricity and promote a quicker development of agriculture with less government investment.

MMH production costs are rather low, amounting to approximately 3-4 fen per kWH whereas the production cost of the small thermal cost or diesel-fuel power stations is about 10 ten or more per kWh.

China’s experience shows how the standardization of equipment, cost reduction technology in works handing over the running of the MMH power to the local community, complete control of the local community over the use of power for industrial development return on investment to re-invested in industrial and community development. The cost reduction for water resistance devices to be used in place of surge shaft, use of third harmonic voltage excitation system, cost of which is 50% of the older system requires less maintenance and repair work in comparison with SCR exitor which often requires mechanical processing and dealing with the commentator erosion. In China following the rapid development of MMH stations, small power networks have arisen in many places helping to improve the reliably of power supply. Usually the installed capacity of the grid on a county level (district level) ranges upto 10000 kws. Their experience is to improve the reliability of power supply, the establishment of a small local grid is necessary. A small local grid must be equipped with several units in order to bear the heaviest load to stabilize the running of the grid should have a sufficient installed capacity and enough spare capacity.

Similarly the Pakistan experience can also be utilized as they have worked with determination to keep appropriate technology in MMH utilization of local material association of the local people, design suited to local condition and living, implementation, management, operation and maintenance to communicate because the remotness of villages their small population and lack of income generated enterprises combined to make rural electrification by grid extension uneconomical. Hey also developed new designs for the civil work and new approach in implementation is adopted in designs that emphasis the use of local rather than imported materials and manual labour.

Villagers designated by the community operate and maintain the plant thus envolving local operators with technical assistance for technical staff, learning various tasks from various appropriate operations because the plant system does not operate a governor. Principal task of operator is to manually operate the light around the village. The operator therefore, is not required to adjust the water turbine continuously to keep pace with changes of electrical load.

Nepal is another country where the government has undertaken small-hydropower programme. Faced with a difficult situation few roads, scattered but dense population in certain parts of the country, rugged terrain, major deforestation, and not indigenous oil reserves, the Nepalese see decentralized hydropower as a promising source of energy. Efforts are made by Balaju Yantra Shaala to localize the small water power installations. This private sector approach to the implementation of a micro-hydro power program illustrates an encouraging alternative to the more costly, bureaucratic governmental approach.

BYS, BTI two prominent organization of Nepal are involved in developing approapriate technology, have emphasized the use of only indigenous equipment, without importing, which could be easier. Although it took them sometime but they were able to successfully fabricate and install number of MMH power stations and over the years have improved their expertise for doing so. All their efforts have been explained in this chapter and they have also emphasized the use of direct mechanical energy for running the rice miller flour mills also emphasized the use of direct mechanical energy for running the rice miller flour mills the processing machinery would be properly integrated into the overall project designs. They also lowered the turbine levels and put the other industrial machinery at a higher floor thus avoiding waiting of the mills floors. They also utilize the mechanical generator for drying of agricultural products using hydro power instead of generating electricity and then to use it to force air passd electrical heaters thus avoiding the costly in between equipments.                                                    Back