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Page 1 As of September 2001 IEA Bioenergy Task38 www.ieabioenergy-task38.org ISO 9001 certified Perspectives on the timing of benefits of forest-based bioenergy Annette Cowie, Goran Berndes, Tat Smith Rural Climate Solutions
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Costs of climate change In 2010, climate change cost: 700 billion USD 0.9% global GDP 400,000 deaths per year – 90% children Climate change + Carbon economy costs 1.2 trillion USD kills 4.975 million DARA, 2012
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Too late to avoid 2° C ? 2° C: target of the Copenhagen Accord to avoid catastrophic outcomes Already increased by 1 degree At least 0.5 degree unavoidable – in train Without immediate and drastic action we cannot meet the 2° C target
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Global Energy Assessment 2012
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Task 38 Negative emissions options Afforestation, soil carbon management Enhanced weathering Direct air capture Ocean fertilisation “BECCS” – Bioenergy+ Carbon Capture &Storage
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Atmosphere Bioenergy – “carbon neutral”
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Global Energy Assessment 2012
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Göran Berndes
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Task 38 Climate change effects of biomass and bioenergy systems IEA Bioenergy “Carbon debt” papers Holtsmark, B. (2012). “Harvesting in boreal forests and the biofuel carbon debt.” Climatic Change 112(2): 415-428. Hudiburg, T. W., Law B. E., Wirth C. and Luyssaert S. (2011). “Regional carbon dioxide implications of forest bioenergy production.” Nature Clim. Change 1(8): 419-42 Lamers P., Junginger M., (2013) " The ‘debt’ is in the detail: a synthesis of recent temporal forest carbon analyses on woody biomass for energy." Biofuels, Bioproducts, and Biorefining, in press. McKechnie, J., S. Colombo, J. Chen, W. Mabee and H. L. MacLean (2011). “Forest bioenergy or forest carbon? Assessing trade-offs in greenhouse gas mitigation with wood-based fuels.” Environmental Science and Technology 45(2): 789-795. Schulze, E.-D., C. Körner, B. E. Law, H. Haberl and S. Luyssaert (2012). “Large- scale bioenergy from additional harvest of forest biomass is neither sustainable nor greenhouse gas neutral.” GCB Bioenergy: 4(6): 611-616. Searchinger, T et al (2009). “Fixing a critical climate accounting error.” Science 326(5952): 527-528. Walker, T et al (2010). Massachussets Biomass Sustainability and Carbon Policy Study. Manomet Center for Conservation Sciences. Zanchi, G., N. Pena and D. N. Bird (2010). The upfront carbon debt of bioenergy. Graz, Austria, Joanneum Research.
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Task 38 IEA Bioenergy Task 38 “Climate change effects of biomass and bioenergy systems” Participating countries: Australia, Brazil, Finland, France, Germany, Netherlands, Norway, Sweden, USA
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Task 38 Objectives of Task 38 Develop, demonstrate and promote standard methodology for GHG balances Increase understanding of GHG outcomes of bioenergy and carbon sequestration Emphasise overall atmospheric impact, whole life cycle Promote international exchange of ideas, models and scientific results Aid decision makers in selecting most effective mitigation options
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Timing statement published July 2013 ieabioenergy.com/ iea-publications/ Annette Cowie, Göran Berndes, Tat Smith and others from Tasks 38, 40 and 43
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Who is asking?
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Life cycle perspective
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Task 38 Consider carbon stock change “direct land use change dLUC” change in land use or management affects C in biomass and soil
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Task 38 Indirect landuse change Outside system boundary Form of “leakage” Off-site carbon stock change, methane, nitrous oxide emissions logging fire drainage of peatlands
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Fritsche, 2009
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Task 38
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Reference energy system Fossil energy source: average or marginal? Conversion efficiency Displacement factor = efficiency bio /efficiency ref x CO2 ref /CO2 bio Nearly always <1
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Task 38 Reference land use Natural forest Integrated food/feed/timber/biomass systems
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Spatial scale? F Cherubini NTNU
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Berndes et al 2011
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Göran Berndes
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Task 38 Different perspectives Stand vs landscape Individual operator vs national government Natural system vs managed system Clock starts at planting vs at harvest Short term vs long term Specific stage vs whole life cycle Biomass only vs integrated forest product system Average vs marginal reference system Debt vs investment
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JRC report http://iet.jrc.ec.europa.eu/bf- ca/sites/bf- ca/files/files/documents/eur2535 4en_online-final.pdf
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Task 38 Climate change effects of biomass and bioenergy systems IEA Bioenergy JRC report Negative conclusion for forest-based bioenergy – too uncertain therefore too risky Ignores forest management impacts on forest growth Accepts as reference “natural carbon carrying capacity” without human intervention Focus on short term “carbon neutrality”
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Task 38 Climate change effects of biomass and bioenergy systems IEA Bioenergy IEA Bioenergy Statement: Policymakers need to consider the big picture - the whole life cycle, the long term, human influences Biomass for energy is usually one of several products from a managed forest Forest C stocks fluctuate (at the stand level) over time and space - a forest is a mosaic of age classes Forest C stock should be considered across the estate A function of management and natural factors May be increasing or decreasing or stable 49
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Task 38 Climate change effects of biomass and bioenergy systems IEA Bioenergy If C stock decreases (relative to “without bioenergy” scenario), this is an emission that must be compensated through avoiding fossil fuels, before bioenergy gives net mitigation benefit Loss in C stock can be minimised by investment in intensive forest management GHG cost is an investment in establishing renewable energy system 50 IEA Bioenergy Statement:
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Task 38 Climate change effects of biomass and bioenergy systems IEA Bioenergy Bioenergy benefits increase in long term Society should choose how to fill the available “emissions space” GHG cost of forest bioenergy is an investment in establishing renewable energy system 51 IEA Bioenergy Statement:
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Task 38 Climate Change Effects of Biomass and Bioenergy Systems IEA Bioenergy Task 38 http://task38.org/ http://task38.org/ annette.cowie@une.edu.au
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Bioenergy Carbon neutral? maybe Climate neutral? Not if you start with existing forest Consider single stand Omit forest management impacts F Cherubini NTNU
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020406080100120 Time (years) IRF no regrowth regrowth Atmospheric [CO2] - impulse response
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F Cherubini NTNU
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0 100 200 300 400 500 600 700 800 900 20406080100120 Year Carbon t/ha Trees Trees + products Trees + products + biochar + bioenergy Unharvested Potential mitigation through wood products, bioenergy and biochar
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F Cherubini NTNU
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Data from Cherubini et al 2009 Excludes indirect land use change
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59 IEA Bioenergy reports
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Task 38 Emissions intensity: CO 2 emissions per unit useful output (kWh electricity, GJ heat, km travelled) Biomass Auxiliary Energy CO 2 emissions Service unit: kWh el, GJ heat, km travelled Calculating the benefits of bioenergy
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Task 38 Global Energy Assessment 2012
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Task 38 emissions per unit output can be manipulated Simple measures can be misleading: Biomass GHG emissions Service unit: kWh el, heat, liquid biofuel Auxiliary Energy
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Task 38 Expand system boundary: consider reference system Emission reduction per unit useful output Biomass Auxiliary Energy GHG emissions Service unit: kWh el, GJ heat, km Coal, oil, natural gas Auxiliary Energy GHG emissions Service unit: kWh el, GJ heat, km
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Task 38 Biomass C stock change 40 80 120 160 200020202040206020802100 0 t C/ha
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Task 38 Biomass use efficiency Biomass is a limited resource Emission reduction per unit biomass Biomass use efficiency =Emissions reduction Biomass C (as CO2e)
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Considering full life cycle, what is the best use of biomass resources? How can land be used to provide energy and meet other needs? How can policies and accounting methods distinguish systems with highest mitigation value?
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Reforestation for timber + bioenergy
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