Agricultural Biomass Availability for Bioenergy Applications in Nova Scotia Michael Main NSAC May 22, 2008
Outline Agricultural bioenergy options Life-cycle energy analysis Biomass / bioenergy crop potential in NS Agricultural waste bioenergy potential
Ethanol and biodiesel from food crops
Coppice for solid fuels Heat, electricity, liquids Pellet fuel
Other fibrous crops for solid fuels / fiber Miscanthus Switchgrass Solid Fuels, liquids Fibers Reed canary grass Fiber Hemp
Biogas, bio-oils Manure biogas digester Wood, hay, straw, manure Bio-oil
Cellulosic ethanol
Bioenergy Life cycles CO2 Biofuel CO 2 Crops Transport and processing Electricity Heat Fuels Fertilizers Chemicals Equipment CO 2 Fuels Electricity Chemicals Equipment CO 2 Based on coal, oil, natural gas
Energy Budgets 14:1 8:1 4:1 3:1 1.5:1
Land use for bioenergy Available lands: Currently unutilized land Improved management of forage lands (current livestock numbers could be fed from ½ of the forage land area) Newly cleared land
Agricultural land area in Nova Scotia Nova Scotia Hectares Hay and haylage 75,000 Pastures 56,000 Grains & corn silage 18,000 horticultural 6,000 Wild blueberry 16,000 Note: High proportion of land is used for forages Note: Provincial Feed grain deficit exists (Statistics Canada, 2006) Unutilized land area (est d) 40,000 Total cleared land (est d) 210,000
Biomass production potential Crop wet yield (T/ha) Land availabl e (ha) odt biomass final product gross energy yield (GJ/y) net energy yield (GJ/y) Fuel replaced coppice 20 40,000 400,000 fuel chips 7,200,000 6,700,000 140 million L LFO grass 9 40,000 316,800 pellet fuel 5,700,000 5,000,000 130 million L LFO ethanol 2,400,000 2,000,000 60 million L gasoline barley 4.5 10,000 39,600 ethanol 270,000 90,000 8 million L gasoline canola 2.8 10,000 24,640 biodiesel 350,000 233,333 10 million L diesel sugar beet 45 10,000 90,000 ethanol 1,100,000 825,000 30 million L gasoline 1. LFO = light fuel oil
Ag. crop energy potential 180 million GJ/y total energy consumption in NS
Nova Scotia Farmland, Historical trends
Nova Scotia soil areas, by CLI class NS total land area is 5,500,000 ha Class 2: Good soils Class 3: Can be cultivated, with improvements Class 4: Limitations; suitable for forage Class 5: Serious limitations for agriculture but can be used for pasture/forage ~ 210,000 ha is currently cleared
Biomass crop potential Production on 40,000 60,000 hectares can develop with no impact on current food production If the beef sector continues to decline, more land could become available. Expanded livestock production could co-exist with expanded biomass crop production, with improved management for higher productivity. This would require strong prices in both sectors.
Biomass crop potential Biomass crop expansion beyond about 60,000 ha would likely require land clearing or displacement of food production Biomass crops are more productive than managed forest, but is improved forest management a better investment? High grain prices may encourage more planting of feed grains Opportunity for combined livestock / biomass crop production Biomass grass for biomass or feed Leaf-stem separation
Agricultural by-product energy Limited current grain production means limited crop residue availability Straws are mainly utilized for bedding, mulches Limited vegetable/fruit crop production Some potential for biogas production from wastes Grains & corn silage horticultural Wild blueberry 18,000 ha 6,000 ha 16,000 ha Substantial manure production Biogas potential
Manure Biogas Dairy Cattle Beef Cattle Hogs Chicken Mink 2006 numbers 22,265 22,501 116,091 2,784,452 422,438 Tonnes manures 327,741 222,760 190,679 101,632 23,128 Gross biogas potential, GJ/y 196,000 80,000 75,000 188,000 32,000 - Potential electricity production: ~ 60,000 MWH/y About 1/2 of this (30,000MWH) might be a realistic goal with at least $0.11/KWH electric price. - Can add other wastes or crop material to a manure digester - Similar co-generated net thermal output
Summary 40-60 thousand hectares or land could be available for biomass crops, providing up to 750,000 tonnes biomass fuels (13,500,000 GJ/y). Manures could provide up to 300,000 GJ/y of biogas Minimal crop residues are available Development depends on strong energy prices and supportive policy Perennial grass or coppice have the greatest sustainable potential