Woody biomass for electricity as an option to reduce GHG emissions possibilities and uncertainties

Transcription

1 Woody biomass for electricity as an option to reduce GHG emissions possibilities and uncertainties KNAW-symposium Biobrandstof en hout als energiebronnen Amsterdam 10 April 2015 Dr. Martin Junginger 1

2 Renewable Energy in the Netherlands Share in 2013: 4.5% vs target for 2020: 14%. Current contribution of biomass to total RE supply: 70% Co-firing: million t wood pellets Source: CBS, Hernieuwbare Energie in Nederland 2013,

3 SER akkoord in 2013 As a part to reach the 14% target, 25 PJ final energy (equivalent to about million tonnes wood pellets) will be co-fired to replace coal in the most modern coal power plants in the Netherlands. The biomass will be subject to strict sustainability criteria, including sustainable forest management, iluc and carbon debt criteria

4 Source: Lamers et al., ch 3, in Junginger, Goh, Faaij,(eds). (2014) International Bioenergy Trade - History, status & outlook on securing sustainable bioenergy supply, demand and markets. Springer, Lecture Notes in Energy, Vol 17 Global wood pellet trade in 2012 Trade flows in 1000 tonnes

5 Basic principle of GHG emission reductions through bioenergy Slow uptake Rapid removal Source: adapted from IEA Bioenergy Task 38 The fact that bioenergy is ultimately renewable is not debated

6 Trends in increment, removals and sink strength for European forests G.J Nabuurs et al. Nature climate change perspective, 18 August 2013, DOI: /NCLIMATE1853

7 Volume of damage (in stem volume) caused by different types of natural disturbance from 1850 to 2010 G.J Nabuurs et al. Nature climate change perspective, 18 August 2013, DOI: /NCLIMATE1853

8 Source: N. Bird, IEA Bioenergy Task 38

9 GHG Balances Of solid biomass and biogas for electricity and heat production Source: IEA, 2012, Technology Roadmap. Bioenergy for Heat and Power

10 Source: Sikkema, Junginger et al, BioFPR Wood pellet chains Swedish domestic use Canadian pellets in NL

11 Basic principle of GHG emission reductions through bioenergy Slow uptake Rapid removal Source: adapted from IEA Bioenergy Task 38 The fact that bioenergy is ultimately renewable is not debated, but the time until the repayment of any potential carbon debt is repaid is under debate

12 Stand-level Source: Eliasson et al. 2011

13 Landscape-level Source: Eliasson et al. 2011

14 Carbon debt & parity points stand level Visual representation of the carbon payback period and the carbon offset parity point, taken from Mitchell [2012]

15 Overview parity payback times Source: 12. Lamers, P., Junginger, M. (2013) The 'debt' is in the detail: A synthesis of recent temporal forest carbon analyses on woody biomass for energy. 2013, Biofuels, Bioproducts and Biorefining 7(4), pp doi: /bbb.1407., DOI: /bbb.1407.

16 Actual and announced feedstock use in pellet production in the U.S. South for Source: Forisk (2014), Abt et al. (2014)

17 Pine plantations in the SE US Typically established in the 1950 s and 60 s for pulp, paper and timber, rotation time between years Demand for traditional wood products currently low increasing use for wood pellet production Only thinnings and small trees (+/- 25% of final harvest) are used for pulp and/or bioenergy, the large trees are used for construction

18 C-debt or credit? US Foresters view: Pine plantations established by men, with the explicit aim to harvest at some point for human use -> moment of planting is reference point. Especially if plantations are 2-3 rotations old, any previous carbon debt (caused by use for pulp & timber) would have already been repaid -> redeeming a credit. Also, moment of planting would be consistent with supply chain LCA approach EU Policy maker view: can incentivize use of tree for pellets or not -> moment of harvest is reference point > debt approach

19 The correct counter-factual What is the most likely& accurate reference (also known as counterfactual) scenario: Protection? (or harvest less frequently) Continued use for timber and pulp & paper & replant? Clearcut and abandon (i.e. natural regrowth)? Or land use change (e.g. conversion to agricultural crops, cotton, or urban development)?

20 The correct counter-factual Source: Spehenson & MacKay, Life cycle impacts of Biomass electricity in2020

21 US SE Forest loss forecasts Urbanization : million acres by 2060 Forest losses: million acres by 2060 (10-20%) (source: Wear, 2013)

22 C-debt mitigation options 1. New (SRC) plantations on degraded/cpoor land -> imminent carbon credit! 2. For managed/commercial plantations: Use of fertilizer and weed control (within SFM limits) increases productivity strongly 3. For plantations: Increased early stand density & use of pre-commercial thinnings Options 2 & 3 cause no additional land use and reduce any C-payback times strongly (+ additional output for pulp & timber), but all need incentives

23 C-debt mitigation options

24 Carbon balance of productive and no-use scenarios [Mg carbon / ha] Landscape level, carbon parity against a hypothetical protection scenario, replacing coal years 26 years 46 years Litter carbon Tree carbon Low productive scenario Medium productive scenario High productive scenario Jonker, J.G.G., H.M. Junginger, A.P.C. Faaij (2014) Carbon payback period and carbon offset parity point of wood pellet production in the Southeastern USA, GCB Bioenergy 6 (4), pp

25 C-debt mitigation options

26 C-debt mitigation options Number of seedlings sold in the US SE increased from 600 to 800 million between This is at least partially a direct consequence of the expected higher demand for low-quality thinnings for energy (electricity, pellets, 2 nd gen fuels etc.) Source: Personal correspondence with Jeff Wright, ArborGen and Steven Myers, FRAM, June 2013

27 Southeast Forest Carbon Projections Natural Forest Source: Bob Abrt el al Plantation 27

28 Southeast Forest Carbon Projections Source: Bob Abrt el al

29 So what to do Fundamental choice between using land as a carbon bank, or as a resource for material & energy My preference is to actively stimulate the sustainably increased productivity and use of wood for materials and energy rather than to lock it away But this will not happen automatically energy & material markets and (sustainably governance) policies required

30 Dutch sustainability criteria Agreed between Dutch utilities and NGOs in March 2015 Biomass 100% FSC (equivalent) certified by 2023 (starting 10% in 2016) Fund to actively certify (US) forests against FSC standards 70% GHG emission reduction against EU reference value for fossil electricity No conversion of (semi-natural) forests after 2008 Written evidence that C-stocks in forest must be maintained or increased <50% (volume) of wood extracted from any catchment area for energy

31 Assessing C-debt risk on pellet plant level Carbon Stock change (due to harvest) 2. Speed of carbon accumulation (after harvest) 3. Reference forest system (counterfactual wood / land use) 4. Regional forest carbon stock reference 5. Reference energy system (counterfactual fossil fuel use)

32 Assessing C-debt risk on (pellet) plant level Source: Junginger et al., Sustainable bioenergy wood supply chains development of a tool to assess first order risks of carbon debt and indirect effects on a project level. December 2014

33 Final thoughts Depending on your perspective, one can calculate zero years to several decades (even centuries) of C-debt but choosing the right chains can be done The discussion is often too focused on carbon only - ultimately it is only one of many factors influencing environmental, social and economic sustainability Outlook beyond wood for electricity: use to replace coal for the next 10 years is not necessarily a bad idea, (intermittent renewables, BECCS) but Stimulating sustainable feedstock production is ultimately important, independent of use for electricity, heat, fuels, biochemicals or traditional timber & paper

34 Thank you for your attention! More information? We want your input: Working paper on Sustainable biomass for energy and materials: A greenhouse gas emission perspective Available at: Comments welcome!