Recent developments in LCA parameters

Transcription

1 UNECE/SWST Joint Session on Innovative Wood Products are the Future October 2010, Geneva Recent developments in LCA parameters Dr Richard Murphy Division of Biology, Imperial College London & Porter Alliance

2 Presentation What we do know and is well established Highlight some areas of significance Future perspective on timber (and other) LCA information in policy LCA knowledge must be combined with other knowledge

3 Key aspects of LCA ISO Use of the ISO standards is a key quality indicator critical review is required for comparative assertions System boundary needs to be as inclusive as possible, the functional unit objective, and appropriate methodological choices LCA does not do everything some questions or aspects are not readily assessed using LCA e.g. biodiversity values, some dimensions of land use

4 What we do know An oven dry tonne of wood material contains 3.67 kg of CO2 removed from the atmosphere Wood supply and carbon stock on land is sustainable over rotations From IEA Task 38: Answers to ten frequently asked questions about bioenergy, carbon sinks and their role in global climate change

5 What we do know There is an accumulating benefit from managing forests for production of wood products - credit for the avoided fossil resource consumption can be substantial and cumulative after Nabuurs (1996) see Forestry Commission Information Note: Forests, Carbon and Climate Change

6 EU 15 carbon stocks & flows Net gain 14.6 Mt C per annum From IIED/ECCM (2004) Using wood products to mitigate climate change

7 What we do know Overall equilibrium carbon storage in forests and in forest products is highest when:- Forest stands accumulate carbon rapidly and for a long time before they are harvested Forest litter decomposes slowly Wood products have a long life Substituting wood-based products for fossil energy intensive products brings life cycle benefits assuming like-for-like performance

8 Significant areas for attention Need to understand and represent diversity within broad product groups improved precision Need to recognise uncertainty in the LCA datasets and, to an extent, in the methodology and to account for this Capture the complexity in several manufactured wood products in manufacturing and in performance

9 Diversity in broad wood product groups 1 m3 pulpwood supply in Spanish (SP) and Sweden (SW) case studies by Garcia-Gonzalez et al. (2009) 395 MJ/m3 Spain 370 MJ/m3 Sweden Int J LCA (2009)14,

10 Uncertainty Wood, end of life Much uncertainty over landfilling of wood is it a GHG sink or a GHG source? Highly sensitive to assumed degradation rate 2500 Kg CO2 eq/tonne Landfilled (100 Year Time Frame) % 20% 40% 60% 80% 100% IPCC default SINK SOURCE Gardner et al., 2002 Carbon Sequestered Methane Emissions Mann & Spath,2001 Degradation Rate of Landfilled Wood (%) Electricity Credits Damen & Faaij,2003 Overall Greenhouse Gas Balance DEFRA WRATE from Carly Whittaker TS E C B ios ys

11 Uncertainty - Diversity in service life Durability of wood products - often by expert estimates or desired service lives e.g. for treated wood Use of ISO (2006) Factor based approach to service life prediction

12 Uncertainty and complexity Rational approach permits inclusion of complexity and assessment of several wood performance aspects over this range of potential service lives e.g. LCC, GHG balances

13 Future Perspectives for LCA The intensive focus on biofuel LCAs (particularly GHG balances) is creating a significant spill over effect for attention to all land-based industries incl. food, biopolymers etc. Increased recycling of competitor materials will substantially improve their life cycle profiles. It will benefit the wood industries to engage with the waste management/recycling sectors to close our life cycles in beneficial ways

14 Future Perspectives for LCA contd. LCA as an approach is becoming diversified into:- - Attributional LCA ~ traditional, product-focus average data - Consequential LCA system effects and orientated, prospective ( what if analyses), use marginal data higher uncertainty clca is of high interest to policy-makers because it addresses system level effects, gives warning of perverse outcomes Challenging but could/will be highly rewarding

15 Key messages. Use LCA for what it is good for Be critical Analyse for and communicate uncertainty Fill data gaps = self help

16 Thanks to EC Project FP7 EnergyPOPLAR, Cost Actions E9, E31 UK Research Councils - NERC (TSEC-Biosys), EPSRC, BBSRC (BSBEC) Collaborations with industry wood preservation, composites, coatings and joinery, UK Forestry Commission, SHR, Modcell, Univ of Bath. Carly Whittaker, Jo Mundy, Nigel Bell, Jem Woods, Miao Guo and Bill Hillier