What is LCA? LCA methodologies

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1 RENEWABLE ENERGY TRAINING PROGRAM MODULE 8 BIOENERGY Life cycle Analysis of Woody Biomass Energy Rob Bailis Associate Professor Yale School of Forestry and Env. Studies 4 December 212 What is LCA? How is it done? Key concepts Examples LCAs for bioenergy Charcoal in Brazil Overview 12/2/212 Bailis ESMAP Solid Biomass 2 1

2 What is LCA? 1. Goal and scope definition 2. Life cycle inventory 3. Impact assessment 4. Interpretation 12/2/212 Bailis ESMAP Solid Biomass 3 LCA methodologies 1. Goal and scope definition: defines the system boundary and functional unit and level of detail required for input data. An example from my research: Goal: compare environmental impacts of producing charcoal using hot tail kilns, as is current practice, and using container kilns with pyrolysis gases utilized for cogeneration What happens when you add cogeneration to a traditional charcoal production system? Boundary: nursery to plantation gate (prior land use not included) Functional Unit: 1 ton of carbon in charcoal 12/2/212 2

3 LCA methodologies 2.Life cycle inventory Cataloging material flows along all stages of production: All input/output (I/O) data to define the system Sources of data include: direct observation life cycle inventory (LCI) databases previous/similar analyses 12/2/212 Life cycle materials and processes Units a Per hectare Per Functional Unit (FU) Nursery stage Water liters Electricity kwh KCl kg K 2 O Mono ammonium phosphate (as N) kg N E 5 2.3E 5 Mono ammonium phosphate (as P 2 O 5 ) kg P 2 O E 4 1.1E 4 CaNO 3 kg N E 3 3.3E 3 Blend of NPK fertilizers (as N) b kg N E 4 3.4E 4 " (as P 2 O 5 ) kg P 2 O E 3 1.7E 3 " (as K 2 O) kg K 2 O E 4 3.4E 4 (NH 4 ) 2 SO 4 kg N E 4 7.E 4 MgSO 4 kg Sowing and management stage Water for irrigation liters 15, 15, Water transpired by trees liters 262,8, 262,8, 1.9E6 1.4E6 Fuel (diesel) liters Glyphosate (applied for new seedlings) liters Blend of NPK fertilizers (as N) c kg N " (as P 2 O 5 ) kg P 2 O " (as K 2 O) kg K 2 O % KCl (plus micronutrients) kg K 2 O Tractor p Harvesting and transport of feedstock Fuel (diesel) liters Feller/buncher p 3.3E 4 3.3E 4 2.3E 6 1.8E 6 Skidder p 3.3E 4 3.3E 4 2.3E 6 1.8E 6 Cutter/delimber p 3.3E 4 3.3E 4 2.3E 6 1.8E 6 Loader p 3.3E 4 3.3E 4 2.3E 6 1.8E 6 Kiln infrastructure Bricks tons Mortar tons Steel tons.17.1 Pyrolysis and cogeneration inputs Fuel (diesel) liters Lorry 16t p Water (for cooling in cogen units) d m 3 NA NA /1.6/3.7/6.7 Electricity demand c kwh NA NA 52/52/64/97 Pyrolysis and cogeneration outputs Charcoal output tons Charcoal carbon output tons Electricity to grid c kwh NA NA /274/613/1122 Tar c kg /22// 3

4 LCA methodologies 3. Impact assessment: Converts raw input/output data into meaningful measurements May be assessed as raw data, intermediate, or final impact Example: climate impacts Raw data: tons of CO 2, CH 4, and N 2 O Intermediate impact: aggregate global warming pot l (GWP) Final impact: temperature increase or physical/economic damages 12/2/212 LCA methodologies 4. Interpretation: an assessment of the outcomes of the inventory analysis and impact assessment, including sensitivities. 12/2/212 4

5 LCA methodologies Additional considerations: Treatment of co products Most bioenergy systems multiple products How do we allocate impacts? Temporality (past, current and future impacts) Attributional and Consequential LCA Land Use Change (LUC) 12/2/212 Bioenergy LCAs strong focus on GHGs Life cycle GHG emissions of biopower technologies per unit of electricity generation, including supply chain emissions (land use related net 12/2/212 changes in carbon stocks and land management impacts Bailis ESMAP are excluded). Solid Biomass Co firing is shown for the biomass portion only (without 1 GHG emissions and electricity output associated with coal). From IPCC SSREN. 5

6 in comparison to fossil options 12/2/212 Bailis ESMAP Solid Biomass 11 Example Innovation in Brazilian Charcoal Production Brazil is the world s largest charcoal user > 8% used by the metallurgical industries source of carbon and energy Rabo Quente kilns 7% of production 12/2/212 Bailis ESMAP Solid Biomass 12 6

7 Brazilian Charcoal Production Energy sources utilized in Brazil s metallurgical industries from 197 to 21 Mtoe Other sources* 2 Wood and charcoal Electricity 1 Coal and coke Natural gas and coke gas * "Other sources" include fuel oil and diesel, LPG, and other petroleum derivatives. 12/2/212 Bailis ESMAP Solid Biomass 13 The majority of feedstock originates from plantations, but Charcoal production in Brazil by source of wood (199 21) 6 Million tons of charcoal 4 2 6% 3% 7% Natural forests Plantations 4% Source: IBGE, /2/212 Bailis ESMAP Solid Biomass 14 7

8 Charcoal production by state in 21 (IBGE, 212) Millions of tons 1.5 Legal Amazon Silviculture Natural forest 12/2/212 Bailis ESMAP Solid Biomass 15 There are also large energy losses Energy flows in charcoal production in Minas Gerais, Brazil (1978 to 28) as lump charcoal, other materials (charcoal fines and tar), and losses 8 Mtoe losses Tar and charcoal fines Lump charcoal Miranda et al /2/212 Bailis ESMAP Solid Biomass 16 8

9 and emissions Emissions measured in traditional earthmound (EM) kilns and a variety of improved kilns reported in the literature showing emissions of each GHG weighted by its 1 year global warming potential (Bailis 29) 12/2/212 Bailis ESMAP Solid Biomass 17 Alternative technologies DK biochar reactor with Stirling Engine DPC charcoal reactor flaring noncondensable gases CML charcoal plant RIMA pilot plant with container kilns 12/2/212 Bailis ESMAP Solid Biomass 18 9

10 Rima s concept (Vilela, 21) Ciclo Contínuo Carbonização (12 horas) Secagem (6 horas) Resfriamento (12 horas) Carregamento (3 horas) Descarregamento (1 hora) 12/2/212 Bailis ESMAP Solid Biomass 19 Rima s concept (Vilela, 21) 12/2/212 Bailis ESMAP Solid Biomass 2 1

11 The LCA System boundary 1. Raw Material Acquisition 2. Raw Material Transport 3. Material Production and/or Transformation 4. Product Transport 5. Product Use Path 1: Rabo Quente kiln Metal refining Nursery Plantation Path 2: Container kilns with gas capture and cogeneration 12/2/212 Bailis ESMAP Solid Biomass 21 Mineral Coke supply chain Results GHGs kg CO2e per 1 kg carbon in charcoal % 119% 52% 66% Other* Co products (tar and/or electricity) Woodwaste decoposition Pyrolysis and cogen Eucalyptus carbon storage Total 9 Hot tail kiln No cogeneration Cogen w/gas, Tar displacement Cogen w/gas+tar Cogen w/gas+tar+ww *"Other" includes emissions from nursery operations, sowing and management, kiln construction, harvesting, and transportation. In total, these processes contribute 2 7% of all GHGs. 12/2/212 Bailis ESMAP Solid Biomass 22 11

12 Results water use Approx range of water use from 1 t C in mineral coke (from SimaPro) millions of liters per 1 kg C in charcoal 2 2 Hot tail No cogeneration Cogen w/gas (tar coproduct) Cogen w/gas+tar Container kilns Withdrawals (inc. consumption) Cogen w/gas+tar+ww Hot tail All container kilns Consumption only Co products (tar and electricity) Pyrolysis Eucalyptus transpiration Sowing and management Other * Total *"Other" includes water used in the nursery stage for irrigating seedlings as well as water embodied in the materials and processes used for harvesting, transportation, and kiln construction. 12/2/212 Bailis ESMAP Solid Biomass 23 Results other impacts Ozone Depletion Potential (ODP) Photochem. Oxidation (PCO) Acidification (ACID) Eutrophication (EUT) (mg CFC 11 eq) (kg C2H4 eq) (kg SO2 eq) (kg PO4 eq)x1 Hot tail kiln No cogeneration Cogen w/gas, Tar displacement Cogen w/gas+tar Cogen w/gas+tar+ww 12/2/212 Bailis ESMAP Solid Biomass 24 12

13 Aggregating results??? 16 Pt Brick all processes Aug12 Metal all processes, gas cogen + tar copro Aug12 Metal all processes, gas and tar cogen Aug12 Metal all processes, no co products Aug12 Metal all processes, gas tar and ww cogen Aug12 Radioactive waste Bulk waste Human toxicity Eutrophication Acidification Ozone formation Ozone depletion Global warming 1a Total Comparing product stages; Method: EDIP 23 V1.3 / Default / Single score 12/2/212 Bailis ESMAP Solid Biomass 25 Concluding thoughts LCA is a powerful tool to compare technological options But proceed with caution! More than just GHGs When we introduce multiple impacts, comparing and/or aggregating is risky Only meaningful if local context is taken into consideration 12/2/212 Bailis ESMAP Solid Biomass 26 13