Biogas: Fuel of the Future

Once considered an intermediate technology fit only for the underprivileged "Third World", biogas is now generating interest in the West as a cheap, renewable source for energy.

Prabha K. Singh

October 31, 1978 |

The inhabitants of Mukimpur village in Bulandshahr district pledge not to marry their daughters in villages which have no biogas plants.
                                                                                                                         - The Times of India

Gimmicky as it may sound, That pledge betrays a genuine anxiety, based ironically enough, on the very success of the biogas experiment. Though still in its infancy, the 50,000 plants installed under the Khadi and Village Industries Commission's (KVIC) biogas programme are already producing 99.82 million cubic metre of gas, equivalent to 62 million litre of kerosene valued at Rs 62.49 million, and 11.20 lakh tonne of high quality organic manure worth Rs 50.86 million.

Not surprisingly, a number of the farmers, suddenly catapulted into unaccustomed wealth, reacted as if their families were under seige. A typical complaint was the one made by an Uttar Pradesh villager who said: "The women in my house no longer work. They don't make dung cakes, collect firewood,... every woman is becoming a queen by herself. The added income from the farm causes jealousy and when we white-washed the house last month and installed a gas light, we found we were isolated from the entire village. The only way out now is to dig up my plant or make sure my neighbours get one."

Fortunately for the old man, his plea was answered by Jashbhai J. Patel, then technical advisor to the KVIC. "That man eventually helped us install 450 plants in the area," recalls Patel, whose pioneering work earned him international recognition as the undisputed "father of biogas technology".

Cheap Source: The case for biogas is undeniable. Once considered an intermediate technology fit only for the underprivileged "Third World", biogas is now generating interest in the West as a cheap, renewable source for energy.

Germany which built the first plants in 1947 and abandoned research after some initial failure, recently sent a four member delegation headed by Dr Gunther Hilliges, of the Bremen Overseas Research and Development Association, to aid and study the successful Indian experiment.

"Although discovered in 1870, biogas would have remained an obsolete technology in the West," Dr Hilliges told India Today, "if it wasn't for the oil price hike of 1974. Suddenly farmers all over Germany are sending us letters regarding the possible installation of plants."

The team, which studied a number of villages in India, is planning to publish a handbook in several African, Asian and South American languages "promoting the enormous developmental advantages of these plants."

Fuel: An average family of five requires 50 cubic feet of gas per day for cooking and providing four hours of light between sunset and early morning. To feed a plant this size, however, the family needs at least five heads of cattle, each producing approximately 13 cubic feet of gas per day.

Predictably, 60 per cent of the plants belonged to rich farmers owning more than four hectares of irrigated land and of the rest, only 11 per cent were owned by farmers having less than five cattle. The poorest, landless farmers were suddenly denied access to the now precious dung cakes.

A village housewife - city comforts

"One way out of the problem," said Patel, "was to build a community plant." The Council for Industrial and Scientific Research (CISR) built the first one in Kodumunju village in the Karimnagar district of Andhra Pradesh. Constructed at a cost of Rs 85,000, the plant produces about 4,480 cubic feet of gas per day to meet the requirements of 12 to 15 families.

Other Benefits: An unexpected bonus was the dramatic improvement in health and hygiene. Says Patel: "There was a time when we could tell we were approaching the village from the characteristic, overpowering stench of festering faeces. Now that we have built community toilets to feed the plant along with other night-soil and agricultural refuse, flies and mosquitoes have almost disappeared - as have most stomach and intestinal disorders, trachoma and malaria."

Since then, several villages have put up community plants, most notably in the Kaira (Amul dairy) region of Gujarat where landless, caste shepherds own milch cattle. So successful was the venture that a businessman, M.V. Patel, has decided to operate a commercial plant. Half his dung requirements are purchased from local shepherds and the by-products - fuel and fertilizer - are sold at a substantial profit.

Of the estimated 980 million tonne of cattle dung available in the country, 30 per cent is burnt in the form of cakes, most of it in the Gangetic plain. How wasteful this method of cooking is, was revealed in an experiment which showed that only 11 per cent of the heat potential of the dung was utilized, the rest being turned to ashes. If on the other hand, the entire amount of dung was fed into gas plants, it would produce 36,260 million cubic metre of gas, enough for the fuel requirements of 87.45 families.

Saving: Further, of the 0.25 tonne of coal equivalent used as domestic fuel in India, at least 34.4 per cent consists of wood, dry leaves and agricultural wastes. The introduction of biogas would directly affect this 34 per cent of the rural population thus saving, at a conservative estimate, Rs 400 crore of valuable wood annually.

"This is one way of halting deforestation and enjoying the ecological benefits accruing from it - increased rainfall, less soil erosion and the preservation of rapidly disappearing wildlife," said Professor R. Guldager who has worked with bio-gas plants in Somalia and Ethiopia and now heads a department for development and settlement at the Technical University, Braunschweig. Indeed, so promising are the fuel possibilities that "the proper recycling of waste can produce as much energy as the nation's entire consumption of oil," said a former managing director of Indian Oil.

Added to this is the attraction of free, high quality organic manure. So rich is the humus and nitrogen content of the manure that unsuspecting farmers reaped double the yield in root crops such as potatoes, carrots and turnips. Studies undertaken by the Humus Institute revealed a number of instances where the introduction of nitrogenous manure doubled the vegetable yield per acre. "Organic manure is free from weeds, white ants, soil grubs and is the only way of improving the basic structure of the soil," said Patel, "whereas, chemical fertilizer works in a lopsided fashion."

Fertility: A study undertaken by Professor A.K.N. Reddy of the Indian Institute of Science, Bangalore, demonstrated the tremendous economic and developmental advantages of biogas manure as against chemical fertilizers. To produce 2,30,000 tonne of nitrogen annually, a nation could either build one coal-based plant or 26,150 small, village level biogas plants.
The former would cost $140 million (Rs 136 crore) to build, half of it in foreign exchange, and would consume coal equivalent to the energy requirements of 550 villages. The latter would cost $15 million (Rs 13.5 crore) less, would require no foreign exchange, be able to use renewable energy resources and would be environmentally sounder, as it is non-polluting. Further, it could be brought to production within a matter of months, given the right organization as against the couple of years required to build a big plant.Moreover, the benefits of development, would be spread more evenly in 26,150 centres rather than being concentrated in one area. The biogas plants, for instance, would generate 130 times as much employment in the most backward areas.
Undoubtedly, biogas can become a major energy source for rural India and give much needed impetus to rural development. It remains to be seen whether the much-vaunted rural programmes of the Janata Government would exploit its full potentials.