In 1995, an initiative was taken by BAIF, Pune to establish a community biogas based electricity generation plant at Basavanahalli with the financial support from international Energy Initiative. The plant which has a maximum capacity of producing 20 cmt of gas by processing 500 kg of dung, was commissioned in August 1996. Biogas can be an important component of renewable energy supply providing energy and manure.
Biogas Plant-Operation and Maintenance
The villagers have formed a Gram Vikas Sabha to operate and maintain the biogas plant. All the families in the village are members of the Sabha and the executive committee consists of 10 members drawn from different sections of the community. Every house has been provided with a fan and a tube light. A youth has been trained and appointed by the Sabha operating the system. The water is supplied for one hour every morning and evening. Light is provided for 3 hours from 6 pm to 9 pm or on local demand. The timings for water and power supply is determined by the Sabha. Individuals have been provided with a passbook for recording entries on collection of cow dung and distribution of slurry. The Sabha meets regularly and discusses matters relating to the smooth operation of the system.
At present, gas distribution for cooking is not encouraged as the required management systems for gas distribution at the community level are yet to be perfected. The gas generated in the plant is fed into a 7.5 kva generator which operates with 20 percent diesel and 80 percent gas. The electricity so generated is used for pumping drinking water by operating a submersible pump. The electric supply line is drawn 1.0 m below the existing grid electricity lines using the same poles.
The slurry coming out of the biogas plant is dried on sand bed filters. This enables faster dung cake formation which will be easier to distribute among the farmers. The filtered water is again collected and recycled for mixing with fresh dung for feeding into the plant. For every kilogram of fresh dung contributed by the farmers, 850 gram of dried cakes are returned. The villagers who do not have land or cattle also contribute cow dung to the biogas plant by collecting dung from surrounding areas. The slurry in such cases is sold by the contributors to other interested farmers. There is very little loss of energy in community biogas based electricity generation and distribution system. The total cost of production and consumption is cheaper and highly decentralised.
Many social benefits though intangible accrue from the use of this plant. These are improved health and sanitation, reduction in women's drudgery, increased family labour efficiency. With surplus water supply for domestic use, sewage let out in open drains was envisaged. To avoid this pollution, the villagers are planning to grow coconut and banana in their backyards using this waster water.
The capital cost of establishing a unit capable of supplying electricity and water for 100 families is Rs. 5,00,000. The monthly expenses to run the plant works out at Rs. 1,500 which includes salary of the operator, minor repairs and diesel cost. This is met by collecting a monthly nominal fee of Rs. 20 from each family. It is also planned to generate more revenue by increasing the utilities by operating a flour mill and giving special supply to families during marriage or on special occasions. The viability of these plants will improve if the size of the village is large. A large number of families means more dung and less individual expenses leading to increased generation of electricity.
No comments:
Post a Comment