Fuel mix in rural India is characterised by the predominance of biofuels. Among these, fuel wood accounts for over 50% of our energy consumption (NCAER, 1985). Dung cakes constitute the other major source of rural energy – about 60% of dung collected in the country is burnt as fuel. Continued reliance on these sources is, one the one hand, depleting the natural resource base and, on the other, preventing growth of the rural productive sector, especially industries. This national scenario repeats itself in much of the Bundelkhand region, including Jhansi district. The extent of deforestation in the district is reflected in the low forest cover of 6.5% (NWDB, 1993) - much of it caused by pressure of fuel wood. Agriculture, the main occupation in the district, relies on one crop and shows large scale seasonal unemployment. The productivity of land has been steadily declining due to loss of soil nutrients and this is reflected in the high proportion of wastelands in the district - 18% of the geographical area (NWDB, 1993) which is one of the highest in Uttar Pradesh. The loss of nutrients is being compounded by diversion of cow dung away from the fields. The current crisis of rural energy is affecting a number of user groups: domestic households, artisans like potters, industries and the urban informal sector. The several manifestations of the rural energy crisis in Jhansi are:
Response Strategy DESI Power has been launched as a major initiative in identifying the possible sources of renewable materials which can be effectively used in the decentralised production of electricity. The two major classes of raw materials identified are animal residues like cow dung and biomass materials such as lantana, ipomea, and mustard stalk. Further, it is proposed to integrally link energy technologies with livelihood-based enterprises. Fig. 1 demonstrates the linkages between energy technologies and livelihoods. The major technologies that have been selected are: Gasification Technology A biomass-based gasifier has a reactor which acts as a gas reactor and is coupled to a cooling and cleaning train. The reactor has two sections. The bottom portion consists of a mild steel shell lined with ceramic material 60mm thick. The top portion is a double wall with stainless steel shell. The bottom shell has air nozzles and is used for ignition and for monitoring the combustion zone. A water seal isolates the bottom portion of the reactor. The gases released during pyrolysis combust in the combustion zone at about 1200-1400"C. The products of combustion move through the charged zone where they get reduced to carbon monoxide and hydrogen gas. This gas is used as feedstock for thermal applications and for mixed feed into diesel generating sets. The cleaning train is used to scrub the gas for removal of tar and dust particles. The first commercial biomass gasifier unit initiated by DESI Power has been commissioned at TARAGram, Orchha, Madhya Pradesh. The details are given in box 1. Briquetted Fuel In the absence of fuel wood, cow dung is used for cooking, burning of bricks and majority of thermal applications. The wastelands and water streams of Bundelkhand are inundated with growth of lantana and ipomea respectively. These biomass species are not hitherto used for domestic cooking or for burning as these are reported to emit toxic fumes during the initial combustion. Using simple means of pyrolysis, these materials can be very effectively converted to char. This process gives an effective yield of 20-25% based on dry biomass, i.e. 4-5 tonnes of biomass provides 1 tonne of char. This char is powdered, blended with appropriate binders and extruded to manufacture briquettes. In the case of Jhansi, the additives are clay (upto 20%), cow dung (upto 5%), and cellulosic waste from handmade paper production (upto 10%). Different combinations of additives are added to control. The speed of combination, heat content and sparking characteristics of the briquetted fuel. For this purpose, a briquette machine has been designed with a productivity of 1 tonne of briquettes per day which is powered with a 5HP motor. The briquette has an outer diameter of 50mm, a central hole of 10mm and length to suit the application. The cost economics of briquettes manufactured is given as under: Biomass collection (per tonne)
Pyrolysis (per tonne)
Briquetting (per tonne)
Market survey has shown that good marketing potential exists for sale of the briquettes at a selling price of Rs.4,001 - to Rs.4,500/- per tonne. Besides charcoal briquettes, the machine can also be used for briquetting of powdery biomass materials such as mustard stalk, sun hemp and groundnut shells. To ensure sustainability, it has been observed that every village having access to a water stream can collect upto 500 tons of biomass from a radius of 2.5 kms on a renewable basis. This material is converted to efficient fuel through livelihoods. Synergy Systems Within the regional context, DESI Power has examined the market potential for synergy systems which provide multiple uses for a given resource. The technologies identified are: Biogas Generation. The Bundelkhand region has a cattle: human population ratio of 1.1:1. Milk production is a major livelihood but very little of the cow dung is used as manure. Biogas plants are not widely used in this area even though the technical feasibility and need appears to be very high. Amongst large number of families surveyed on the Jhansi - Babina road, house owners with cattle holding in excess of six who also have land for agriculture are very keen to install biogas plants of 2cu.m capacity or even higher capacity. The biogas would be used for cooking and the slurry would be composted to be used as fertiliser. Mangal water wheel cum turbine The Bundelkhand region has land terrain which is very conducive for harvesting of water through check dams. In most cases, a head of three metres is possible. A local inventor has set up a prototype of water wheel with turbine system for direct pumping of water. This technology has a potential of being adapted for generation of electricity and efficient pumping for irrigation. The techno economic feasibility of this package is very favourable for establishing integrated energy and water services in the area and even extending this to fish cultivation. DESI Power plans to implement a prototype unit for determining a long term marketing strategy.
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