The biogas learning curve.

The first thing to appreciate is that no biogas project here runs in isolation. They are always integrated some way or another with complementary alternative technologies, and social schemes. For example, I visited a village school, which boasts a 50 m³ floating dome digester with a concrete base and steel dome. It is the school holidays, but many of the children were there for a summer sports camp run by one of the staff. What a greeting I was given. I had to walk between two rows of children clapping out a rhythm, which stretched from the school gates to the biogas digester. And the press were there too – my photo was in the papers the next morning, I was shown it by someone we visited next day - and the ladies who cooked the school dinners with the biogas, plus the ‘father of the school’ the headmaster. Lots of photos were taken and the children, well everyone actually, seemed really pleased I was there. We had trouble getting away; all the children wanted to shake my hand at least once.

For good measure, during one of my many cultural interludes with this remarkable man, we visited the Sri Lakshmi Narasimha Swamy temple, built on the top of a hill, a monument to human endeavour. There were hundreds of pilgrims there, stalls selling everything including the type of plastic tat typical of a British seaside town. There was music, chanting, flags flying and monkeys. I was permitted to join the throng passing in, and round, in semi-darkness, and out of the temple and all in bare feet. Except me, who had been wearing trainers and was the only wuss in socks.

In the old town of Hyderabad I went to a complex of Ashram, Temple and the Good Will Model School. Twin digesters lie side by side, gobar fed, and providing gas for the temple and the Ashram, which is home to some seventy poor and mostly elderly people. In many of these places, the elderly are expected to work, but in this charitable institution they live out their peaceful old age, being both cared for and fed – cooking by biogas.

The area we are covering is the Nalgonda district and we stopped off to see the gentleman in charge of the Non-Conventional Energy Development Corporation of Andhra Pradesh (NEDCAP). Nedcap, like Prakratic, are introducing domestic AD for the some reasons. The government target is for 500,000 digesters. Again, households are selected on the number of cattle they own. The digesters are 2m³ and require 25kg dung for each m³ of gas, so therefore 2 or 3 cows are required. Murali Krishna and the DO talked together for a while. When a pale green lizard ran across the wall and dropped down beside the table I felt my camera finger twitch, but the men gave it not a glance and offered me more tea and water. Everywhere I go in India, I am offered water at the very least. Even in the Delhi market, where I perched beside a high class outfitters window, just to watch life go by and recover from the heat, a boy was dispatched from inside with a glass of water for me despite the fact I was not, nor going to be, a client.

We journeyed out into farmland, past fields of harvested rice. The paddies, enclosed by their low mud walls were dry now, and goats grazed on the stubble. Lorries and auto-trucks went by, swamped by bags of grain, and bright yellow stacks of rice straw stood ready as cattle fodder for later in the year. There were small groves of bananas and sweet orange, and fields were edged with tall coconut palms. There are massive irrigation canals criss-crossing the land, totally devoid of water at present. The villages and farms in this part of India appear more affluent than those I saw in Rajasthan. Many of the mud dwellings had been abandoned, leaving just the occasional, painted wall, to be replaced with decorated concrete structures with outside steps to the flat roof.


The Nedcap digesters are simple in design and construction, and there are many being built here. The framework is a dome of weld-mesh covered in chicken wire, with openings for inlet and outlet. When in position the mesh is covered in a cement/sharp sand mix, rather dry and ‘short’. This is pushed on from the outside against a pad held by a man inside the dome. He escapes through the inlet aperture. When dry, an inside layer is pushed on against the outer. Inlet and outlet pits are built of concrete later. Photographs can be a nightmare! We get mobbed by laughing children. They’re all very good, and move if you ask them, but they love being included in the photo, and have to be shown the result. I don’t know why we’re such a source of amusement – just because we’re strangers I suppose. We stopped at the house of the village president, who already has a digester installed and running. We were invited in to view their biogas stove and here I had my first cup of biogas tea.

The Sri Sai Madhava Vermi Culture farm at Duggepally is just another of those wonderful little nuggets I keep coming across. This is where we had been invited for lunch on the second day. A slim, softly spoken lady farmer, k. Shashikala Reddy, had, with some of her girls, prepared a meal, an enormous meal – they always are - with much concern for a feeble western constitution. There had been phone calls between her and Murali Krishna as to what I could eat, and when we sat down to do so, the girls lurked by the kitchen door, watching me. I accused them of waiting for me to run from the room, with my mouth on fire. They giggled and one brought me more water to be on the safe side. I have to admit I managed it all, not the quantity, but the variety – and the pudding – well, we don’t get desserts like this in British Indian restaurants. It was bready, and spicy and fruity, and enough for an army.

Widowed a few years ago, Mrs Reddy decided to support herself and her son on a small farm, and under the guidance of Murali Krishna, did so organically. Twenty five head of cattle were introduced chiefly to feed the biogas plant. This runs a small generator which powers the drip feed irrigation system in the sweet orange groves. Gobar from neighbouring farms was brought in to increase the gas yield, resulting in a good deal more digestate than could be used as fertilizer in the farm. Mrs Reddy then embarked on another enterprise – that of vermiculture. There are low covered sheds with row upon row of worm casts. At one end, surplus digestate and any other organic material is fed to the worms, which progress along the row as they eat. At the other, the casts are sieved and bagged, ready to be sold. This lady has won several awards for her enterprise, and rightly so.

Another nugget – not biogas this time, but solar power. Padigipally village is a jewel in the LED village campaign. This is little village of 230 households; some 900 people, and boasting 63 stand alone streetlights. The lamps in these streetlights are 12 LEDs powered by a small battery, charged with a 12 volt solar panel. It’s surprising that there isn’t more done with solar power, given the relentless intensity of the thing. In this village, which does actually have grid electricity, each household also has been provided with two lamps of 4 LED bulbs apiece. It is the first village of it's kind in India, and they only finished it in April. I expect they heard I was coming. Once again, I was welcomed into the tiny houses for photographs, and there was the usual line-up of giggling children.