As opposed to giant corporates abandoning fossil fuel and the global one per cent stepping off their high horse. Despite this juxtaposition, collective effort is not without its cascading effect, making every new sapling count and every batch of vermicompost matter. Trusting in this wisdom, this camp of environmentally conscious citizens would like to point you to your next big personal goal biogas.

“A lot of us are concerned about the environment. This is just a means to make use of the waste effectively. The waste you throw out is fed into the device instead and you get gas; it cuts down on pollution; it lowers your expenditure on LPG cylinders; you get liquid fertiliser as a byproduct. When everything turns out to be an advantage, why shouldn’t we do this?” reasons Vel Murugan, a recent biogas convert.

Breaking down biogas

Biogas is the mixture of gases produced (mostly methane and carbon dioxide) from the anaerobic digestion of organic matter, agricultural waste, manure, municipal waste, plant material, sewage, green waste or food waste. This treatment allows for the controlled capture of methane that would otherwise be released into the atmosphere, directing it for efficient energy use instead. At the individual level, one would need a biogas plant with a simple input-output mechanism, a collecting bag/bottle/tank for the gas and a special burner to complete the set-up.

“This is just another device for the house,” begins M Jagadesh, owner of Tamil Nadu Biogas. “We feed in the waste collected from the house and it produces the gas over the course of the day. This can be used as kitchen fuel whenever you need it. The byproduct of the process is wastewater. This makes for a good fertiliser for plants. Now, this becomes a cycle,” he explains.

You need cow dung a hundred kilograms of it to kickstart the process through the introduction of bacteria in the biogas unit. It takes about two weeks to reach optimum levels, after which you can begin feeding in the waste. “You won’t get the same force as with the LPG cylinder but it gives you enough. And it also depends on what waste you use only kitchen waste, only cow dung or a combination of the two,” says Vel Murugan.

While the biogas is always pitted against the LPG when presented as a viable alternative, it does measure against the conventional fuel admirably, opines Parthasarathy Arumugam, director – technical head of B-Sustain Energy Projects. “In LPG cylinder, the gas is pressurised; this pressure is reduced using a regulator and then it reaches the burner. Hence, it gives you more control. Here, it only offers a medium flame (given that the storage is not pressurised and regulated). You cannot cook as fast as you can with LPG; it would take an additional 5-10 minutes. We have to adapt to it accordingly,” he suggests, adding that we moved to the LPG from the viragu aduppu in the same way.

What more, customer testimonies show that food tastes better and stays good for much longer when cooked with biogas, he points out. Ellammal vouches for that, having used biogas in her house for over five years now. A nutrition coach, it was the search for better food habits that turned her attention to the means of cooking it too. And biogas seemed to be the best alternative. “There is much difference in taste. It takes a while to heat; so you can notice the difference in the food. And the nutritional value is preserved,” she says. It’s the difference between cooking meat on the pan and on an open-fire barbeque, chips in Vel Murugan. And the wastewater, too, has other uses besides making for good fertiliser, says Jagadesh. “You can replace your surface/toilet cleaner with this liquid. It’s basically bacteria. It will break down the dirt and waste and clean up everything. Leave it on the surface for 10 minutes or so and wash it away. Not only does it clean the surface, but it also clears out the drainage pipes and removes any obstructions,” he shares, from his experience.

Costs and compensation

As much as its benefits are plain to see, the one thing that makes people hesitate is, of course, the cost of the enterprise. A biogas installation can cost anywhere between Rs 10,000 and Rs 60,000, depending on its capacity and method of installation. And the question that immediately comes up in response to this is that of return of investment. While Jagadesh and Parthasarathy are quick to say “Do you expect a return of investment in the washing machine you buy or the smartphone that doesn’t last longer than two years?”, they assure that it is entirely possible to get your money’s worth in just a few years.

Jagadesh, on his part, has managed to cut down on his LPG cylinder expenses. From purchasing nine cylinders a year, he’s brought it down to four. Even if you keep the price of a cylinder at Rs 800, that’s Rs 4,000 a year you’d be saving, he points out. Beyond this simple reassurance, he has another measure for your returns. “Waste management is a huge expenditure for the government. At the household level, we throw out waste worth at least Rs 1,500 every month. Be it the kitchen waste or leftover food. This amounts to Rs 15,000 a year. You can round it up to Rs 20,000 if you take into account festival days and special occasions like birthdays and weddings when waste generation increases drastically. So, this is how much we put out in the form of waste every year. It is this that you’ll be able to reuse with biogas,” he offers.

The way forward

Working towards a personal goal of bringing biogas to every household by 2025, Jagadesh has been conducting training workshops to equip like-minded people with the know-how of installation. Vel Murugan managed to set up the biogas plant at his house after the day-long workshop. He’ll soon be helping a couple of friends do the same. Jagadesh recently initiated an online course to impart the knowledge as well.

Parthasarathy, on the other hand, talks about the need to look at the bigger picture and find a place for biogas in it. When the rest of the world is moving past zero-emission goals and looking at negative emission (carbon capture), we need to do our part in stepping up the reach of biogas to every industry. “Germany, in 1997, had only 800 biogas plants. In the next ten years, it increased to over 7,000. Today, they are the pioneers in the biogas movement. They use domestic and agricultural waste to generate biogas and they have an extensive pipeline system to supply the gas.

They have the facility. It’s not the same here. We generate the gas and purify it; then, we need to invest in the compressor, transport, etc. Then, we don’t have a market for it in the 20-km radius; so, we have to take it further. There are more costs built into it. When 50 per cent of the investment goes into this, how will we attract more investors? Now, the Indian government wants to promote biogas and have a target of 5,000 by 2025. But, we don’t know how they are going to make it happen. Before bringing in the policy, we have to look at the facilities available,” he surmises.

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