To meet the domestic fuel and bio-fertiliser needs, 3,680 biogas plants are planned to be set up in rural areas by June 2012, according to Pakistan Centre for Renewable Technologies.
The Centre says that over 2,100 family-size biogas plants — against the target of 2,500 — have already been set up throughout the country.
The programme, supported by NGOs, farmers’ bodies and the rural support programme netwok, is being implemented by Pakistan Biogas Development Enterprise.
The construction of 30,000 biogas installations planned for next four years will be funded by the four provinces including Khyber Pakhtunkhwa with an investment of Rs2.7 billion. A sum of Rs244 million will be disbursed as investment rebate support to households.
Often animal waste is usually not used productively. In Landhi alone, a suburb of Karachi city, around 0.35 million cattle heads are kept in a three kilometre area that produces thousands of tons of waste but 80-90 per cent of it is thrown into the sea. A Canadian firm Highmark Renewables and the KESC jointly intend to set up a biogas plant at a cost of around $70 million which would produce 30 megawatts of electricity besides 400 tons of residue bio-fertiliser.
The biogas plants will considerably decrease the domestic fuel cost. Moreover, biogas will contribute towards environment protection, sustenance of ecosystem and conservation of biodiversity.
According to PCRT gas produced in a small bio-digester which contains about 20 kg dung should be enough to meet the fuel needs of a small family. A bio-digester for any number of animals can be designed. However, the plant must be water/gas-tight and enough manure and water should be added to it every day.
Biogas plants are fairly popular worldwide. There are almost two million biogas plants in India and the facilities have been built even in the United Kingdom and the US through official patronage. Around 89 such plants in the US are consuming 13 per cent or 95,000 tons of waste to produce about 25,000 megawatt of electricity that is sufficient for 2.3 million households.’
There is a huge potential for production of biogas in the country. There are currently around 47 million big animals in Pakistan. Even if 50 per cent of their drop is collected, availability of fresh dung comes to 233 million kg a day that can produce around 12 million cubic meters of biogas per day. The fuel requirement of over 20 per cent of the population could be met only from biogas. It will also produce 19 million tons of bio-fertiliser per year.
Around 70 per cent of population in Khyber Pukhtunkhwa lives in rural areas. Most farmers have two or more cattle head whose dung mixed with an equal quantity of water can be used to produce biogas. Any farmer having at least three animals can set up this plant with a one-time investment of Rs40,000 —50,000.
If individual farmers cannot afford the cost, a few families with domestic animals could jointly install such a plant in their neighbourhood. And by selling the gas to families that do not contribute manure for having no animals, the maintenance expenditure, if any, could be financed with this money.
Over 4,000 biogas plants were installed between 1974 and 1987. But with the withdrawal of official financial support, the pace was slowed down and since then only 6,000 plants were installed till 2006. Firewood, dung and crop residues are major sources of energy for rural and low-income urban households. In 1992, firewood provided fuel to about 60 per cent such households followed by dung in dry form at around 18 per cent. To save deforestation, biogas gas is a viable alternative.