For irrigation diesel & electricity is main fuel.Diesel price is increasing & grid electricity unavailable in rural areas of Bangladesh.In many grid connected areas,load shedding is very frequent.So,it’s time to think about renewable fuel sources for irrigation.Practical Action installed few biogas based irrigation pumps and working to scale it up.
North Channel is an island/char situated in Faridpur district under Dhaka division at Bangladesh. It is almost 12 km long and 8 km wide. 98% people of this 50 years old land are dependent on agriculture. They mostly produce rice, wheat, maze and vegetables. Lot of domestic animal is available here which is mostly used in agricultural land. They often forced to sell their animal in dry season (April-June) due to lack of animal food. As rivers and cannels water level goes down irrigation becomes very difficult and costs more manpower, time and money. Those who can’t afford these can’t do anything except to wait for rain. There have almost 300 household size (1.2 cubic meters to 4.8 cubic meters) biogas plants there, although lots of them are not in use. Main reason is, it replace fuel such as wood, dry leaves or cow dung which is cheap. Replacing these 5 taka/kg fuels does not add much value to their lifestyle (78 taka=1 USD). As a result they often find the repair and maintenance of biogas plant difficult and less productive. Practical Action, Bangladesh is now working there to solve the problem of farmers and to add more value on biogas.
The technology is estimated to reach 50 thousand poor households with more than 500 thousand beneficiaries within next 5 years.
Peoples under the project are using shallow engine where biogas is used as primary fuel. Using this they are threshing 400 kg paddy every hour which costs 35/45 taka only. In traditional system 1 labour is needed to thresh 400 kg paddy that costs 400 taka or 20 kg paddy as wage. Payback period is 2 years.
Beneficiaries using 3 inch boring pipe in deep tubewell they can irrigate their land in dry season.All they need for these is a biogas driven shallow engine. Using diesel as primary fuel in pump cost 70-80 taka per liter where using pump with biogas costs diesel of only 10-12 taka,rest of the fuel are biogas which is virtually free if produced from own plant.We have converted the traditional diesel engine to a dual fuel engine and trying to give decentralized technical solution to the end users.
If enough funds are available they will spread it in large scale throughout the country. Government, different INGO/NGO, micro finance institutes can help farmers so that they can use biogas for a more valuable work.
Conversion technology is easy and instruments are locally available. It replaces costly diesel rather than less costly fire wood/cow dung. It increases productivity.
By-product of the biogas plant can be used as compost. Generator can be used in place of pump to produce electricity.
Practical Action, Bangladesh
Practical Action, Bangladesh (International agencies)