Biogas plants to meet fuel, energy shortage
Sep 26, 2011 2 Comments
Focus on biogas plants

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.
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After a few mistakes were spotted in the above printed version of the article, the original text of the article is hereby reproduced.
Biogas plants to reduce deforestation and domestic fuel budget
By Tahir Ali
Under the project “development and promotion of biogas technology for meeting domestic fuel needs of rural areas and production of bio-fertilizer”, the Pakistan centre for renewable energy technologies (Pcret) plans to install 368 biogas plants in rural areas by June 2012.
Launched in 2008 with a target of 2500 such plants, Pcret has already installed over 2100 family size biogas plants in different parts of the country.
Earlier, based on a feasibility study, a programme implementation plan for domestic biogas of Pakistan was finalised with the support of rural support programmes network, NGOs and farmers organisations and is implemented by Pakistan biogas development enterprise. Though it, the construction of 30,000 biogas installations in 4 years will be supported in four provinces including Khyber Pakhtunkhwa with a total investment of Rs2.7bn. Rs244mn would be disbursed as investment rebate support to the households who spend on the technology.
However, the potential is too enormous to be satisfied with this number. Animal waste is usually wasted (see picture). In Landhi Karachi alone, around 0.35mn cattle-heads are kept in a 3km area that produce thousands of tons of waste but 80-90 of it is thrown in the sea. A Canadian firm Highmark Renewables with the help of KESC plans to establish world’s biggest biogas plant at a cost of around $70 million that would produce up to 30 mega watt of power and 400 tons of residue bio fertiliser.
With inflation and energy shortage and costliness aggravating with each passing day in the country, biogas plants could considerably decrease the domestic fuel budget and lessen burden on national power grid. Moreover, biogas will also contribute towards environment protection, sustenance of ecosystem and conservation of biodiversity.
According to a Pcret report, a family size biogas plant annually 10056Kg wood or 22200 Kg animal dung or 1104 lit kerosene oil or 540 kg L.P.G or 9000 Kwh of electricity.
Gas produced in a small bio-digester which contains about 20 kg of dung should be enough to meet the fuel requirement of a small family. Based on these calculations, a bio-digester for any number of animals can be designed. However, the plant must be water/gas-tight. Enough manure and water must be added to it every day.
Biogas plants are fairly popular in Pakistan’s neighbourhood and even developed countries. There are almost two million bio-gas plants in India and the facilities have been built even in UK and USA through official patronage. Around 89 such plants in the US are consuming 13 per cent or 95000 tons of waste to produce about 2500 mega watt of electricity that suffices for 2.3mn households.’
Despite its simplicity and huge potential, the production of biogas has not been given due attention in Pakistan. There are currently around 47 million big animals in Pakistan. A medium size animal drops around 10 kg of dung per day. Even if its 50 percent is collected, the availability of fresh dung comes to 233 million kg a day that can produce around 12 million cubic meters of biogas a day. Since 0.4m gas could suffice the cooking needs of a million Pakistanis, the fuel requirement of over 20 percent of them could be met only from biogas. It will also produce 19 million tons of bio-fertilizer per year, which can boost agricultural productivity.
Khyber Pakhtunkhwa too, despite having one million camels, 6mn cattle, 2mn buffaloes and over 12mn sheep and goats, has failed to utilise the waste of these animals to produce biogas which can be used for cooking and power generation and its residue could be used as fertiliser and which has the potential to reduce both the fuel bill and deforestation in the country.
In the cattle breeding and dairy farm in Charsadda, a bio gas plant has been in operation but the innovative technology has not been disseminated on mass scale in the province.
It seems strange as to why to reduce the speed and scale of deforestation especially in the forest-rich Malakand and Hazara divisions, biogas plants have not been installed or the attention of the locals not drawn towards this enormously fruitful and cheap source of energy so far.
Around 70 percent population in the province lives in the rural areas. Most farmers have two or more cattle whose dung mixed with an equal proportion of water can be used to produce biogas. Any farmer having at least three animals can establish this plant with a one-time investment of Rs40,000 to 50,000.
If individual farmers are not ready or cannot afford the expenses, a few families with domestic animals could jointly install such a plant in their neighbourhood. And by selling the gas to families that cannot contribute manure daily for having no animals, the maintenance expenditure, if any, could be financed with this money.
The government needs to announce more attention and funds to spread this technology to countryside. Media should create awareness among the rural community and NGOs and foreign investors should be encouraged to spread it.
Over 4000 biogas plants were installed in Pakistan by the government between 1974 and 1987. But later it withdrew the financial support which reduced the growth rate of this technology and only 6,000 plants were installed till 2006 since then.
A typical biogas plant consists of a digester where the anaerobic fermentation takes place, a gasholder for collecting the biogas, the input-output units for feeding the influent and storing the effluent respectively, and a gas distribution system.
Firewood, dung and crop residues are major sources of energy for rural and low-income urban households. In 1992, firewood provided fuel to at about 60% of rural and low income families followed by dung in dry form at around 18%.
Only 4% of Pakistan’s total area is covered by forest with only 5% area protected. To control reforestation adoption of biogas is a best technology in Pakistan.