ASSESSMENT OF THE POTENTIAL OF SUSTAINABLE FARMING SYSTEM THROUGH FARM LEVEL ENERGY GENERATION: A CASE STUDY OF SIJUWA VDC, MORANG DISTRICT, NEPAL By Umesh Adhikari Examination Committee Dr. H.P.W. Jayasuriya (Chairperson) Prof. V. M. Salokhe Prof. S. Kumar Dr. P. Soni Asian Institute of Technology School of Environment, Resources and Development Thailand April 21, 2009 A thesis report submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Agricultural Systems and Engineering
BACKGROUND Over 2/3 of the total population in Nepal are engaged in agriculture which contributes less than 1/3 of the total GDP Farm mechanization is gradually taking place in Nepal Nepal relies solely on the imported petroleum products as a primary fuel source Huge amount of agricultural residues are generated as byproducts of agricultural production system ?
Fuel price has increased rapidly in recent years, increasing the cost of farm operations Farm mechanization process, a dire need of the country, may get retarded owing to the increased fuel price If mechanization process is retarded, it would create a gap between energy requirement and supply in agriculture Excessive reliance on non-renewable energy sources such as fossil fuel and fuelwood has added to the environmental pollution and is not sustainable Local agro-processing industries are facing acute power shortage in the country PROBLEM IDENTIFICATION
There is a need to organize the energy generation and utilization pattern so that local energy production potential is fully exploited Certain percentage of fossil fuel can be directly replaced by Jatropha oil, which can be produced locally Agricultural residue based briquetting technology can provide sustainable cooking fuel source Biomass gasification based power production system can provide sustainable and reliable energy source for village mills RATIONAL OF THE STUDY
The overall objective of this study was to assess the fuel and energy requirement of the farm production system, explore the agricultural based energy production potential, and to suggest strategies and necessary intervention so as to minimize the fuel imports, while promoting the farm mechanization, through the case study in Sijuwa VDC, Morang district, Nepal. OBJECTIVES
Specific objectives 1.To estimate the current and future fuel and energy requirement for both mobile and immobile agricultural machinery at different farming system levels and the agricultural products processing mills located in the area. 2.To explore the agriculture based energy production and utilization patterns and potential leading to optimize the localized, farm-level energy self-sufficiency. 3.To recommend suitable residue management practices, necessary processing facility, and technology transfer to meet the future energy demand in a sustainable manner. OBJECTIVES
RESEARCH METHODOLOGY Data Collection Primary data:Household survey—Sampled Mills survey—All Secondary data:Various sources Farmers classification Small - area < 0.5 ha Medium - area 0.5 to 1 ha Large - area >1 ha Scenarios considered Present scenario —Existing situation Mechanized scenario — Complete replacement of animal power by equipments — Cropping intensity increased to 300%
Computations Present scenario Mechanized scenario Energy input and output for major cereal crops√ - Fuel requirement√ √ Residue production and utilization√ √ Agri. residue based energy production potentials√ √ Energy balance matrix√ √ RESEARCH METHODOLOGY
Recommendations for Sustainable Energy Approach a)Jatropha cultivation area A = Cultivation area (ha) F t = total annual fuel consumption (lit) P c = Percentage of fuel to be replaced (%) Yl = Oil yield of the Jatropha plant (lit/ha) b)Briquetting plant C b = Processing capacity of briquetting plant (kg/hr) Q = Quantity of residue available for briquetting (kg) T = Annual operating hours of the briquetting plant (hr) c)Gasification plant Based on the total energy requirement of the village mills Recommendations for Sustainable Energy Approach a)Jatropha cultivation area ( volumetric replacement ) RESEARCH METHODOLOGY
GENERAL INFORMATION ON STUDY AREA Study area Household survey TotalSampled Area:30.43 km 2 Household: Population: Mills survey Mills1111
Summary of percentages of household, land owned and land cultivated by different farm categories RESULTS AND DISCUSSION
About 36% of the farmers owned bullocks, 49% owned he- buffalos and only 2.7% owned tractors. About 70% of the farmers owned either diesel-run pump set or electric motor as irrigation power source Rice, wheat, maize and spring rice were the major cereal crops Cropping intensity was around 200% for each farmer group Farm labor use was not significantly different among farmer groups; spring rice consumed the highest and wheat consumed the lowest RESULTS AND DISCUSSION
Energy input and output from different crops RESULTS AND DISCUSSION
Crop wise and total diesel used by farmers for different crop cultivation at present scenario RESULTS AND DISCUSSION
Farmer wise diesel requirement in mechanized scenario RESULTS AND DISCUSSION ?
Theoretical residue production and energy potential from major crops at present scenario Crop Yield (ton) Residue type RPR Quantity of residue (ton) LHV (MJ/kg) Energy (TJ) Rice Straw Husk Wheat1232.6Straw Maize Stalk Cob Spring rice Straw Husk Total RESULTS AND DISCUSSION
Available residue and energy production potential at present CropResidue Residue Yield (ton) Collection Efficiency (f g ) SAFEUF ASR (ton) ARF (ton) TAR (ton) LHV (MJ/kg) AEP (TJ) Rice Straw Husk Wheat Straw Maize Stalk Cob Spring rice Straw Husk Total RESULTS AND DISCUSSION
Theoretical residue production and energy potential from major crops in mechanized scenario Crop Yield (ton) Residue type RPR Quantity of residue (ton) LHV (MJ/kg) Energy (TJ) Rice Straw Husk Wheat Straw Maize Stalk Cob Spring rice Straw Husk Total RESULTS AND DISCUSSION
Available residue and energy production potential in mechanized scenario CropResidue Residue Yield (ton) Collection Efficiency (f g ) SAFEUF ASR (ton) ARF (ton) TAR (ton) LHV (MJ/kg) AEP (TJ) Rice Straw Husk Wheat Straw Maize Stalk Cob Spring rice Straw Husk Total RESULTS AND DISCUSSION
Monthly electricity and diesel consumption by village mills ParticularsElectricityDiesel No. of mills 101 Mean Consumption (kWh/month)/ (lit/month) Std. Deviation399.1 Minimum (kWh/month)/350 Maximum (kWh/month)/1700 Sum (kWh/month)/ (lit/month) RESULTS AND DISCUSSION
Number of plants Area required (m 2 ) Present scenario Small14127 Medium26236 Large43391 Mechanized scenario Small65591 Medium68618 Large Recommendations for Sustainable Energy Approach a) Recommendation on Jatropha cultivation to replace 20% of diesel RESULTS AND DISCUSSION
b) Recommendation on agricultural residue processing facility Considering the current fuelwood consumption and energy use of agricultural residues, about 4731 tons of agricultural residues based briquetting facility would be required Assuming that the machine can be operated 300 days annually and 16 hours daily, the processing capacity of the machine required to fulfill the briquetting need of the village was calculated as 986 kg/hr. c) Recommendation on gasification set up for village mills A 50 kW power plant that run on the gasification of biomass would be enough to fulfill the power requirement for all the mills in the village. To run such a plant, about 613 tons of biomass is required annually. RESULTS AND DISCUSSION
Annual energy demand of Sijuwa VDC Biomass (ton) Fossil fuel (lit) Electricity (kWh) Fuelwood (ton) Present scenario Small farms Medium farms Large farms Processing Mills Total Mechanized scenario Small farms Medium farms Large farms Processing Mills Total RESULTS AND DISCUSSION
Plan 1 Fulfill the energy of the village mills by generating 50 kW electricity through the gasification of agricultural residues Fulfill the household cooking energy demand of the villagers by briquetting agricultural residues Replace 20% of the total fossil fuel by the producing biofuel locally. Energy balance matrix 1 Type Available total Distribution Cooking (briquetting) Mills requirement Farm operations (biofuel) Surplus / (deficit) Present scenario Bio-mass (ton) Biofuel (lit) Mechanized scenario Bio-mass (ton) Biofuel (lit) lit of biofuel at the current situation and lit of biofuel for the mechanized scenario 59 ha of land at present and 169 ha of land at mechanized scenario 30 plants per household at present and 85 plants per household in mechanized scenario Excess residues can be briquetted and supplied to urban areas RESULTS AND DISCUSSION
Plan 2 Fulfill the energy of the village mills by generating 50 kW electricity and producing 50 kW for village lighting through the gasification of agricultural residues Fulfill the household cooking energy demand of the villagers by briquetting agricultural residues Replace 50% of the total fossil fuel by the producing biofuel locally. Energy balance matrix 2 Type Available total Distribution Cooking (briquetting) Mills requirement Farm operations (biofuel) Surplus / (deficit) Present scenario Bio-mass (ton) Biofuel (lit) Mechanized scenario Bio-mass (ton) Biofuel (lit) lit of biofuel at the current situation and lit of biofuel for the mechanized scenario 147 ha of land at present and 423 ha of land at mechanized scenario 74 plants per household at present and 213 plants per household in mechanized scenario Deficit residues should be imported from other village at present and supply excess briquettes to urban areas in mechanized scenario RESULTS AND DISCUSSION
Energy balance matrix 3 Type Available total Distribution Cooking (briquetting) Mills requirement Farm operations (biofuel) Surplus / (deficit) Present scenario Bio-mass (ton) Biofuel (lit) Mechanized scenario Bio-mass (ton) Biofuel (lit) Plan 3 Fulfill the energy of the village mills by generating 50 kW electricity and producing 100 kW for village lighting through the gasification of agricultural residues Fulfill the household cooking energy demand of the villagers by briquetting agricultural residues Replace 100% of the total fossil fuel by the producing biofuel locally. lit of biofuel at the current situation and lit of biofuel for the mechanized scenario 295 ha of land at present and 846 ha of land at mechanized scenario 149 plants per household at present and 426 plants per household in mechanized scenario Deficit residues should be imported from other village at present and supply excess briquettes to urban areas in mechanized scenario RESULTS AND DISCUSSION
1.At present scenario, based on energy matrix, 50 kW biomass gasification based electric plant and briquetting of the rest residues would be the best option. 2.In the mechanized scenario agricultural residues would be enough to run biomass gasification plant to provide electricity for village lighting, as well. 3.In all three plans considered arbitrarily in this study, surplus/deficit residue and deficit fuel was observed. This indicates need for land use management to optimize residue / biofuel balance for sustainability. 4.An extensive economic evaluation would be necessary so as to assess the economic as well as technical feasibility of adopting the briquetting and gasification techniques in the VDC. 5.A detail study should be conducted using LP technique to explore the best combination of options in terms of economic suitability, as well. CONCLUSIONS AND RECOMMENDATIONS