UNEP International Environmental Technology Centre 1 Converting Waste Agricultural Biomass into Useful Energy Surya Prakash Chandak Senior Programme Officer International Environmental Technology Centre Division of Technology, Industry, and Economics United Nations Environment Programme (UNEP DTIE IETC) HP:

UNEP International Environmental Technology Centre 2 What is biomass Broad term generally refers to any plant or animal matter. Waste Biomass – Main Categories Waste agricultural biomass Forestry residues Wood Animal residues Organic waste from cities and dwellings

UNEP International Environmental Technology Centre 3 Why convert waste agricultural biomass into energy/materials ? Reduced carbon emission a)Due to obviating use of fossil fuels b)Due to avoidance of open burning and rotting (methane emission) Enhanced energy security Enhanced access to energy particularly in rural areas Reduced problem of management, treatment and disposal Additional revenue for farmers Job creation

UNEP International Environmental Technology Centre 4 Global availability of waste agricultural biomass 1 Exa joule = Joules : 1 KiloJoule = Kcals: 1 EJ = 24 million tons oil (approx.) RegionMaize Straw Wheat Straw Rice Straw BagasseTOTAL Africa US & Canada Latin America Asia Europe Oceania TOTAL (765 million tons oil (in EJ/year)

UNEP International Environmental Technology Centre 5 Geographic distribution of availability of waste agricultural biomass RegionMaize*Wheat**RiceCottonSugar # Total China India All Asia Brazil All South America Africa TOTAL of Asia, S. America and Africa *including millet and sorghum **including barley # including minor agro industry (in percent of total)

UNEP International Environmental Technology Centre 6 Technologies for converting waste agricultural biomass into energy Waste Agricultural Biomass to Energy – Technology Options Basic ProcessType of Technology Examples of types of waste handled Biochemical (anaerobic) FermentationFruit and vegetable market waste, waste from fruit/vegetable processing industries Biochemical (aerobic) FermentationSugar/starch containing wastes like waste palm trees Thermo- chemical PyrolysisCrop residues such as wheat straw, rice straw, rice husk, coconut shell Thermo- chemical GasificationCrop residues such as wheat straw, rice straw, rice husk, coconut shell Thermo- chemical Direct Combustion Crop residues such as wheat straw, rice straw, rice husk, coconut shell Physical Processing BriquettingWaste saw dust, waste wood chips

UNEP International Environmental Technology Centre 7 Interesting features of converting waste agricultural biomass into energy Availability of energy source at the place which is energy- starved and conventional energy (electricity and fossil fuels) systems are difficult to reach there Abundant availability -- a large amount is currently wasted by either burning open or by allowing it to rot in the field Little or no pollution; generally no emissions of toxic gases like sulfur oxides and nitrogen oxides Provides a clean fuel for both domestic and commercial use – current patterns of using WAB directly in households usually gives rise to emission of smoke and gases which are very harmful to human health Can provide and alternative source of income to farmers Can spur rural economic development due to enhanced energy availability thus generating jobs Climate neutral

UNEP International Environmental Technology Centre 8 Constraints in converting waste agricultural biomass into energy Dispersed availability spread over wide areas hence challenges of collection Usually voluminous material hence high transportation cost per unit weight – compacting prior to transportation may be required Lower calorific value as compared to fossil fuels particularly oil and gas Some WAB has high moisture content (e.g. fruit and vegetable waste) Some WAB is easily putrescible (e.g. fruit and vegetable waste) Seasonal availability and variations Matching of demand and supply of energy – energy load in rural areas varies widely over the day

UNEP International Environmental Technology Centre 9 Features for considerations when converting waste agricultural biomass into energy Systems required for collection and compacting Considerations for future costs of WAB although it may be available free at present Considerations for alternatives if WAB is being used for some other purposes presently e.g. as domestic fuel, animal feed, mulching for soil etc. Cost of transportation in case of large size WAB2E systems Disposal of ash particularly for WAB like rice husk Flexibility in WAB2E systems to use different WAB Storage of WAB to meet the needs during lean seasons WAB2E systems to have high turn down ratios and/or systems to store energy

UNEP International Environmental Technology Centre 10 What needs to be done for converting waste agricultural biomass into energy Assessment of WAB quantities generated and quantity available for conversion into energy – careful consideration of seasonal variations Characterization of WAB Study of possible systems for collection, compaction and transportation Assessment of present cost structure and projections into future, including cost of transportation Assessment of present energy demand (type and amount) and projections into future Assessment of funds availability Assessment and selection of WAB2E technology Development of a management system for sustainable operations Supportive policy framework

UNEP International Environmental Technology Centre 11 What this project on converting waste agricultural biomass into energy aims at Building capacity on various aspects of WAB2E: assessment of quantification and characterization, assessment of prevailing management systems, assessment and selection of technologies Provide hands-on experience by working at a selected site Demonstration of an appropriate technology which can be further replicated Getting together technology suppliers and entrepreneurs to facilitate commercial uptake of WAB2E systems Support to government on framing conducive policies

UNEP International Environmental Technology Centre 12 THANK YOU For further information: