On the bio-gas trail

From both the economic and the enviromental angle, bio-gas is the ideal solution for rural households: cheap with no recurring maintenance costs and zero impact on the environment. Why hasn’t it been adopted more widely? The benefits of this appropriate technology are numerous and some appear self-evident. For one, there is no emission of greenhouse gases that cause climate change, unlike in the burning of fossil fuels.

Worth the initial investment: The bio-gas plant in Sehli Senauli.

Kamla bhains had the most soulful eyes. Those eyes remained trained on me as I cooled my heels in the cow enclosure, banished from the cowshed itself where the delicate operation of milking Rama, her huge mama, was in progress. This was happening on camera, under strict preconditions — minimum people inside, no loud voices and no sudden movements — as Rama was the nervy, temperamental sort, especially around strangers. I was slightly miffed at missing out on the action. On the other hand, one kick from Rama’s hefty hooves would have sent me sailing over the next two or three hills… So with Kamla of the melting eyes looking on, I occupied myself with trying to gauge how much raw material would soon be generated by the steady chomping of grass kept up by the remaining bovines ranged round the pen: raw material for the brand new plant being set up at Kamla’s owner’s house.

For, I was on the bio-gas trail. Tagging along one day with my husband on a shoot in the Kumaon region of Uttarakhand for his film on bio-gas, I was soon engrossed by the mechanics and possibilities of this appropriate technology. It seems to be such an important — and accessible — renewable energy source for rural areas that I wonder why more people are not making a fuss about it.

Simple mechanism

In the pretty village of Sehli Senauli (Almora district), I saw for the first time the intriguing structural elements of a bio-gas plant in an almost completed state. The main structure is a dome: in the final stages of the construction of the unit, this is entirely covered with earth, with only the outlet pipe in the centre sticking out of the ground. The raw material, well-mixed cow dung and water in the ratio of 1:1, enters the dome from an inlet tank, and is converted into bio-gas under the heat conditions that prevail in the dome. The gas is then led through the outlet pipe mentioned above to the kitchen for use. The slurry or by-product of the reaction inside the dome flows out from the outlet tank, and is ideally allowed to compost (with the addition of dry leaves, etc) for some time before being taken to the fields — this digested dung-water mix is highly fertilizing in effect, more so than ordinary cow dung.

The Kumaon Artisans Guild (KAG), a sterling band of “barefoot engineers” formed by the Ranikhet-based NGO Grassroots (short for Pan Himalayan Grassroots Development Foundation), goes from village to village providing the technical expertise for the building of such plants in houses opting for it. The design they use is called the Deenbandhu model. The units can be of different sizes; the 1 cubic metre unit, for example, suffices for a 3-4 member family and calls for 25 kg of dung daily, for which 2-3 cows are required. A plant of this size currently costs Rs. 13,000-15,000 in hilly areas. Remember, no recurring cash expenses are involved here, in contrast to LPG. There’s a small amount of government subsidy as well as contributions from non-government sources; the household provides the rest of the money, some of it in the form of labour. (An aside: why am I not surprised that the labour component is almost always supplied by the women, hardly by the men? In Kafra village, the two older girls of the house, 10 and 12 years old, also helped.)

The benefits of this appropriate technology are numerous and some appear self-evident. For one, there is no emission of greenhouse gases that cause climate change, unlike in the burning of fossil fuels.

In fact, bio-gas units actually burn off methane, one of the culprits behind global warming. Then, one of the biggest gainers from a widespread use of this energy source — with consequent positive impacts on the whole ecosystem — would be the hapless forests, daily ransacked around the country for firewood.

Technology that enables

Now look at the other side of the coin: deftly cutting grass (and tut-tutting at my incompetent wielding of the sickle), Kavita ki Mummy, proud owner of Kamla bhains and a close-to-functional bio-gas plant, talks of the great distance she or her daughters have to traverse, up and down steep slopes, for their daily quota of firewood (apart from their stock of water). She can hardly believe that soon this onerous, time-consuming task will be struck off their daily drudgery. Kavita and her sisters will have more time for their studies (indeed, in some families such as Dhyani Ram’s in Kafra village, this may be the deciding factor in the dilemma of whether to send the daughters to school or not). The family will live in healthier environs because the cooking will be done smokelessly. And the beauty of this system, as mentioned before, is that the fields will not lose out on precious cow dung, which is reincarnated as an even more potent fertilizer in the process. In a country like India, crowded with small farmers with a few cows and little access to forms of cooking fuel other than wood or cow pats, bio-gas is ideal.

So if everyone gains, and to such a degree, why doesn’t bio-gas have a ubiquitous presence in rural India? Does it have major disadvantages? One issue is the need for skilled masons, for, the building of the dome especially requires precision work, and the working of the plant depends on getting the construction absolutely right. But with dedication and effort, masons can be trained, as shown by KAG/Grassroots. A bigger problem is lack of awareness amongst plant-owners about its use and maintenance. Sometimes the dung-water mixture is not done to the right specification or impurities like straw are allowed to get in, because of ignorance or carelessness, all of which affect the working of the plant. Again, awareness can be increased and households taught to incorporate certain practices into their daily routine for smooth and long-lived functioning of their unit. Another limiting factor is the high initial investment involved for each household, something that can be tided over with larger subsidies from the government.

It is also said that in very cold areas, the system just doesn’t work as it requires a certain temperature. Grassroots’ experience is that in units set up at heights of 4,000-7,000 ft, the efficacy of the plant goes down by 25 per cent for three months in winter, but it does not stop working. And in the absence of any alternative that is ecologically and financially sustainable, bio-gas is still the way forward even in mountain regions, they strongly believe. And obviously so in the plains, in warmer areas.

So now the question is: why doesn’t the government make all-out efforts to popularise this remarkably effective, low-cost renewable energy source, when it can subsidise to the tune of many crores of rupees daily non-renewable fossil fuels like LPG, kerosene and coal? Search me. I remember thinking as I turned for a last glimpse of Sehli Senauli village — its beautiful traditional houses fronted by exquisite, carved doorways, its mellow air as a cat peeked lazily out a window at two laughing women enjoying a breather from the day’s chores — how long will it, and other villages like it, retain its beauty, its way of life? As forests deplete, as food security decreases rapidly in rural areas, more and more people are leaving these villages and migrating to urban areas only to live in slums. Setting up a bio-gas plant is only one of many things needed to turn things around — but it’s a good way to start because it means that villager is saying: I’m going to stop using up scarce forest resources and create the fuel I need. The government needs to encourage that spirit.

You can contact Kalyan Paul of Grassroots at kpaul@grassrootsindia.com for more info on bio-gas in the Himalayas.

Source: The Hindu. Sunday, April 20, 2008