US hardwood s environmental impact: telling the whole story

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1 Produced for the US hardwood s environmental impact: telling the whole story Summary AHEC is engaged in the largest Life Cycle Assessment (LCA) project ever undertaken in the international hardwood sector. The work is being carried out by PE International, a leader in the LCA field, and the results will be released in stages during the first half of The Project forms part of AHEC s efforts to promote a more scientifically based approach to environmental issues in material specification and green building design. The project is also a response to growing international concern about the embodied energy of different building materials. It will rectify common misconceptions, for example the idea that local materials are necessarily better for the environment based on the mistaken assumption that carbon emissions associated with transport are of over-whelming significance in the overall carbon footprint. LCA involves the collection and evaluation of quantitative data on all the inputs and outputs of material, energy and waste flows associated with a product over its entire life cycle so that the environmental impacts can be determined. LCA is applicable to all material sectors so that objective, science based comparisons can be made of their true environmental impact. It also provides a tool allowing industry to identify the most efficient ways of reducing environmental impacts. It ensures that efforts to reduce one impact do not result in environmental degradation elsewhere. The first stage of the AHEC Project involves collection of Life Cycle Inventory (LCI) data for all stages from extraction of American hardwoods in the forest through processing and delivery to the importers yard in Europe and other major export markets. It covers both lumber and veneer products. EPDs simplify communication A major output of the study will be publication of Environmental Product Declarations (EPDs) for U.S. hardwood lumber and veneer in specific export markets. EPDs are like food labels which disclose data on nutritional performance in a structured way without including judgements on health effects. It is up to the individual consumer to judge how to respond to issues like calorific value or fat content. In the same way, EPDs provide clear data on specific environmental impacts, such as Global Warming Potential or Acidification Potential, and allow the consumer to draw their own conclusions. To avoid charges of greenwash, the information contained in EPDs is subject to critical review and independently verified. The AHEC study will lead to the publication of EPDs in line with national EPD programmes in the UK (BRE Environmental Profiles), France (FDES), and Germany (IBU). EPDs simplify the process of comparing and allocating credits to different materials in green building rating systems such as BREE- AM in the UK, DGNB in Germany, and HQE in France. To achieve this, they summarise industry average data for supply of a specified unit of material (such as cubic meter or tonne) to construction sites in the respective countries. EPDs can also be developed by manufacturers for a particular product line, such as a flooring system or item of furniture. Identifying environmental hotspots To find ways of reducing environmental impacts in material production and supply, it is necessary to identify so-called hotspots - stages in the environmental life cycle where impacts are most concentrated. Manufacturers and consumers also need to be able to readily compare the environmental impact of substituting one material for another. To achieve these goals for American hardwoods, PE International has developed an i-report tool allowing non-technical users to compare a wide range of LCA profiles and EPD data by adjusting key variables. Using the i-report tool, Global Warming Potential and other environmental impacts can be readily compared for lumber across 19 different US hardwood species, the full range of lumber thicknesses, an almost infinite variety of transport distances and modes (whether truck, sea, or train), kilning time and efficiency, and the energy mix of the kilns. The i-report allows the user to generate standard reports for specified combinations of these variables. The i-report identifies hotspots by reporting environmental impact data separately for each life cycle stage (forestry, sawmilling, kilning, road transport, sea transport) A powerful story This briefing gives more background on LCA and describes the AHEC Project in more detail. It also provides a preliminary analysis of data generated using the i-report tool. This shows that from forest to delivery in Europe and Asia, carbon emissions during all stages of extraction, processing and transport are more than offset by carbon storage in US hardwood lumber products. Importing American hardwoods for use in durable products like flooring or furniture helps to keep carbon dioxide out of the atmosphere.

2 Life Cycle Assessment: the only effective way to integrate green issues in design Environmental issues are only effectively integrated into material specification and green building design through a scientific LCA based approach. LCA involves the collection and evaluation of quantitative data on all the inputs and outputs of material, energy and waste flows associated with a product over its entire life cycle so that the environmental impacts can be determined. LCA is universally applicable to all material sectors so that objective, science based comparisons can be made of their true environmental impact. It also provides a tool allowing industry to identify the most efficient ways of reducing environmental impacts. It ensures that efforts to reduce one impact do not result in environmental degradation elsewhere. Most previous LCA studies considering wood products have indicated that wood has a strong environmental profile. A recent comprehensive review of 21 studies considering how substituting wood for non-wood materials in specific building applications impacts on greenhouse gas emissions concluded that for each m3 of timber used in place of a nonwood alternative, an average GHG emission reduction of 1.9 tonnes of CO2 equivalent is achieved*. While these studies help to underpin broad wood industry communication campaigns, not all have been undertaken in line with ISO 14040, the series of international standards providing guidance on how to conduct, review, present and use an LCA. The standards cover LCA terminology, data quality and how to assure it, presentation of results and LCA applications and limitations. To avoid charges of green wash it is increasingly important to ensure LCA data is prepared in full conformance to the ISO standards before using it to compare the environmental profiles of different materials Furthermore, most existing studies have focused on softwoods used in structural applications in specific locations and are therefore of limited direct application to American hardwoods. The reality is that the environmental profiles of wood products and potential substitutes vary widely depending on the precise application and location. Preliminary results from the AHEC LCA study, being undertaken in full conformance to the ISO standards, indicate that American hardwoods perform extremely well on a full cradle to grave basis. US hardwoods derive from forests which are expanding rapidly in volume and are generally harvested using low intensity forms for extraction. During manufacturing, a large proportion of energy derives from biomass and few additives are required. Hardwood products tend to be durable with life spans of several decades providing a carbon store and reducing impacts associated with product replacement. At the end of their usable life products are readily recycled or may be incinerated providing a carbonneutral form of energy. *See A Synthesis of research on Wood Products & Greenhouse Gas Impacts, 2nd Edition, Roger Sathre and Jennifer O Connor, FPInnovations Technical Report No. TR-19R, 2010 Growing demand for product-specific environmental information in EPDs Produced for the There is growing demand from specifiers and in green building rating systems for much more precise product-specific information to be supplied in the form of Environmental Product Declarations (EPDs). In ISO terminology, EPDs are defined in ISO as Type III labels that disclose life cycle environmental performance of products. They are not green certificates or claims of environmental superiority (which are Type I labels). EPDs are more like nutrition labels which disclose data on nutritional performance in a structured way without including judgements on health effects. EPDs can be prepared by industry associations for generic products (for example US hardwood lumber ) or by companies for specific product lines. The information contained in EPDs must be third party verified and compiled in line with international LCA standards. Green building initiatives and other interested organisations in many European countries are now coming together to form national EPD programmes to promote consistent development and wider application. Examples include France s INIES/FDES system, Institut Bauen und Umwelt e.v. (IBU) in Germany, EPD Norge (Norway), Swedish Environmental Management Council, and the UK s BRE Environmental Profiles. EPDs already provide the foundation for allocation of material credits in all the leading national green building rating systems in Europe including DGNB (Germany), BREEAM (UK and Netherlands) and HQE (France). Starting this year, France is phasing in a mandatory requirement for EPDs for all consumer goods. Work is also being carried out on interna- 2

3 EPDs provide verified product-specific information across a number of environmental impact categories tional harmonization of EPDs. The ECO Environmental Products Organisation was established in September 2011 with the intent of standardising procedures for EPDs across Europe. Formal Europe-wide standards for preparation of EPDs and for their use in environmental assessment of whole buildings are also being prepared by CEN, the European standards institute. The EU is also developing a proposal that would require mandatory provision of basic EPDs for all products requiring CE Marking. PCRs for Wood Products International standards on EPDs require development of Product Category Rules (PCRs) for each product group to ensure that environmental assessments are performed in the same way and yield the same results no matter who does the analysis. PCRs for specific wood products have already been prepared by national EPD programmes in Germany, Sweden, and Norway. In the UK, a single PCR document has effectively been developed to be applicable to all construction products including timber. The process is led by BRE through their Approved Environmental Profiles system which forms the basis of the BRE Green Guide and the allocation of credits for building materials in the BREEAM building rating system. Similarly in France, EPDs (referred to under the acronym FDES) for construction products must be prepared in line with an official French standard (NF P ) which contains a single consistent set of PCRs for all products. Status of the AHEC LCA Project PE International has completed the first stage of AHEC s LCA project. Life Cycle Inventory (LCI) data has been compiled for the full range of US hardwood lumber products from point of extraction through to point of delivery in major export markets. The second stage is now underway. This involves: compilation of equivalent LCI data for US hardwood veneers; peer review to ensure full conformance to ISO LCA standards; development of an i-report for both lumber and veneers this provides a user-friendly interphase for AHEC Lessons from other material sectors Non-wood material sectors have already recognised the importance of engaging in LCA so that they can readily conform to EPD programs, better control output and ensure their interests are represented in standards-setting processes. Their associations are playing an active role in generating and distributing LCA data. The PlasticsEurope website includes 70 eco-profiles covering the full range of products and processes. The World Steel website provides access to a Life Cycle Inventory providing average data for manufacture of fourteen steel industry products using data derived from 49 sites which it claims are representative of most areas of the world. While LCA aspires to be a scientific discipline, it is inevitable that communication of the results will be subject to manipulation by material sectors to emphasise their own particular strengths and weaknesses. For example, the metal industries lay claim to strong environmental credentials by adjusting study boundaries to increase focus on end-of-life issues (where they may score well on recycling) and to lessen emphasis on energy use during material extraction and processing. Similarly all competing material sectors have an interest in arguing against recognition of carbon sequestration in wood products in LCA standards on grounds of uncertainty over the carbon impact of harvesting in different forest environments. Competing material sectors are also using LCA as the basis for industry-wide programmes which identify environmental hotspots and establish achievable targets for environmental improvement. Communication and lobbying campaigns then focus on ensuring that progress towards these targets is rewarded in green building programmes, government procurement policies and through avoidance of potentially costly environmental regulation. Market expectations are carefully managed so that the industry can always claim it has exceeded targets. For example, the European PVC industry recently published its final Progress Report on Vinyl 2010, the ten-year voluntary commitment launched in 2000 to enhance the sustainable production and use of PVC. The report claims that European PVC companies have met, or exceeded, all targets set by the industry. Much is made of the fact that 253,000 tonnes of PVC is recycled in Europe every year. This achievement looks less impressive when set in the context of the around 8 million tonnes of PVC now consumed in Europe each year, a number not once mentioned in the report. 3

4 Produced for the and AHEC Members to generate productspecific environmental profiles. preparation of EPDs in line with relevant PCRs of various European programs. US hardwood lumber LCI PE has prepared LCI data for kiln dried American hardwood lumber from point of extraction in the forest through to point of delivery to the importers yard. PE used Gabi 4 software to structure and automate the process of LCI compilation and Life Cycle Impact Analysis. Using Gabi 4, PE first drew up a plan of the system being assessed, describing all the processes (e.g. harvesting, sawing, kilning, transport). For each process, data was gathered and entered into the Gabi 4 system on all inputs of energy and material and outputs of product, waste and emissions. This data was compiled from several sources: questionnaires issued to AHEC Members; data for average US hardwood lumber already compiled by the U.S. Consortium for Research on Renewable Industrial Materials (CORRIM)*. detailed information on typical kiln drying schedules for hardwood lumber species in a wide range of thicknesses derived from the USDA Dry Kiln Operators Manual; existing GaBi 4 data, which includes a very wide range of data from public and PE s proprietary databases (e.g. relating to environmental impacts of energy supply and transport modes in different regions). * For several years, CORRIM has been engaged in creating a comprehensive LCI database, in line with ISO standards, covering US forestry and logging practices, saw milling and some aspects of kiln drying. CORRIM s data on forestry was sufficiently robust and extensive to negate the need for PE to gather further primary data on this process. The AHEC project has built on the CORRIM data to allow compilation of environmental profiles for lumber of individual US hardwood species and a range of thicknesses and to accommodate different transport scenarios for delivery to the wide range of world markets. Life Cycle Impact Analysis After compiling the LCI, the next stage of LCA is to undertake Life Cycle Impact Analysis. This stage is automated using Gabi 4 software. It involves three steps: Classification: whereby all emissions from all processes within the scope of the assessment (in this case from hardwood extraction through to delivery of lumber and veneer to importers yard) are sorted into classes according to the effect they have on the environment. For example, substances that contribute to the greenhouse effect are placed in one class, those that contribute to ozone layer depletion in another. Certain substances are included in more than one class. For example, NOx is known to be toxic, acidifying and to cause eutrophication. Characterization: whereby the substances are aggregated within each class to produce an effect score for various environmental impact categories. Normalisation: this step can be undertaken (but is often omitted) to gain a better understanding of the relative size of an effect. Each effect calculated for the life cycle of a product can be compared against the known total effect for this class. For example, the Ecoindicator method compares effects with those caused by the average European during a specified year. There are various different methods and standards used for classification, characterisation and normalisation (such as CML, Eco-indicator, TRACI). The GaBi 4 software allows the user to choose any of the leading methods and results are adjusted accordingly. Output from the Gabi 4 process (after the characterisation step) consists of a series of effect scores for each of the environmental impact categories. The table (page 5) summarises categories typically required to be reported in an Environmental Product Declaration (EPD) and for which well-established standards already exist. However it is not an exhaustive list. There are other impact categories still generally omitted from LCA studies and EPDs due to lack of scientific consensus on appropriate assessment methods. This is particularly true of impacts related to landuse such as biodiversity, desertification and land-use change. Project outputs LCI: data collection on all inputs and outputs for all unit process Peer-reviewed ISO report A key output will be an ISO-conformant report of the study. This lengthy and technicallyoriented report, to be publicly available on the AHEC website, is not itself designed for mass communication purposes. Rather it is required to underpin the credibility of the data used in the EPDs and in i-reports (see below). The 4

5 Impact analysis requires emissions to be classified according to the effect they have on the environment existence of such a report is an essential pre-requisite to the use of LCA data in material specification or any future studies to compare US hardwoods with other wood and non-wood materials. In line with ISO LCA standards, the report must contain a detailed description of the study scope, methodology, system boundaries, functional units, data sources, quality and representativeness, and any assumptions made. It should summarise the results, including sensitivity analysis to show how impacts vary according to key parameters and the contribution of different unit-processes. It will also identify any limitations and uncertainties. This report will be prepared by PE International. However, in order to comply to ISO standards, it must also be subject to critical review by an external panel consisting of at least three members including one recognized LCA expert (panel chair) and additional members with either LCA expertise in wood and/or wood products or who are recognized experts in the wood or wood product sector. A review panel of exceptionally high quality has been constituted for the AHEC study. Members include: Prof. Dr. Matthias Finkbeiner (Chair) who holds the chair for Sustainable Engineering at Technische Universität Berlin and is Chairman of ISO TC207/SC5 Life Cycle Assessment; Dr Richard Murphy of Imperial College London is one of the world s foremost experts on LCA of wood products. He is currently Vice-Chairman of the EC COST E9 network on Life Cycle Assessment of Forestry and Forest Products. Pankaj Bhatia of the World Resources Institute (WRI) based in Washington DC is the Director of the GHG Protocol Initiative workstream within WRI s Climate, Energy, and Pollution Program (CEP). He is a leading expert on GHG Protocol Standards and tools, particularly in the area of corporate greenhouse gas (GHG) accounting and reporting. American Hardwood I-report Environmental effect scores (e.g. Global Warming Potential, Acidification Potential) for US hardwood lumber vary depending on such factors as kilning time (which in turn varies by species), kiln efficiency, the mix of biomass and fossil fuels used to fire the kiln, transport distances and modes. The GaBi model developed by PE is very flexible, so that output can be adjusted against a wide range of parameters. The model for US hardwood lumber: includes 19 American hardwood species; can specify any lumber thickness; can specify the moisture content before the kiln process (e.g. if it was air dried before kilning); Environmental Impact Categories typically required in EPDs 5

6 The AHEC LCA i-report allows environmental profiles to be produced on the fly Produced for the can specify kiln efficiency (which may vary significantly between modern kilns and older kilns); can specify the thermal energy mix used in kiln drying (i.e. the proportion of biomass, gas, or oil); allows adjustment of all transportation distances and modes (truck, rail, ship). The Gabi model also allows effect scores to be broken down according to unit processes (forestry, sawmilling, kilning, transport etc). This allows the contribution of each unit process to the overall environmental footprint to be assessed and hot spots to be identified. The Gabi 4 software is a very powerful tool for undertaking this kind of analysis. However, it is also a very complex piece of software requiring considerable experience and knowledge of LCA to use effectively. For this reason, PE has developed an i-report tool for US hardwood lumber to make these facilities readily available to a non-technical audience. The i-report tool will be accessible on-line or by downloading the software onto a local PC. It consists of two parts: 1. A parameter input interface that allows anyone to enter information for up to 4 scenarios (e.g. varying hardwood species, mix of biomass and fossil fuels for thermal energy, transport distances and modes). 2. A report interface that displays - in real-time - the expected environmental impacts (e.g. Global Warming Potential, Acidification Potential) catagorised by unit process (e.g. forestry. sawmilling, kilning, transport). EPDs for American hardwoods In addition to i-reports, another key output of the project is preparation of Environmental Product Declarations in line with relevant Product Category Rules (PCRs) of various European programs. In the first stage, EPDs will be prepared in line with the following national programmes: UK (BRE Environmental Profiles); France (FDES); and Germany (IBU). Data requirements for EPDs are different to those for i-reports. While the i-report allows generation of very flexible data by varying a ride range of parameters, each EPD can only contain a very limited number of scenarios. EPDs should be based, as far as possible, on industry-average data for the product and market in question. AHEC have agreed with PE that the EPDs now being prepared should provide average data for US sawn hardwood. As environmental profiles for this product are particularly sensitive to kilning time, data in the EPD will be presented separately for slow drying species (i.e. most notably oak) and fast drying species (most other species). Within each group, data will also be presented separately for 1, 2 and 3 lumber. Therefore each EPD will contain output for a total of 6 scenarios. All other key parameters will be set in the EPD using industry average data compiled by PE from questionnaires returned by AHEC Members. The averages currently being used (based on information so far received from AHEC Members) are shown on page 8. AHEC is now encouraging a wider crosssection of AHEC Members to review these proposed averages to ensure they are reasonable and as robust as possible. Environmental profiles in AHEC species guides AHEC already provides comprehensive information on the technical performance of American hardwoods to manufacturers and architects through its Species Guides. These guides will soon be extended to include comprehensive species-specific EPD data for both lumber and veneers. 6

7 Preliminary results from AHEC LCA The following preliminary data derived from the Gabi 4 LCA model for US sawn hardwood highlights some early findings and indicates the sensitivity of the environmental profile to various factors. The focus is on Global Warming Potential (GWP) because this is currently an important focus for environmental policy and consumer interest. Unless otherwise stated, the data is expressed in units of kg CO2 equivalent per kg of US hardwood lumber on arrival at importers yard in Europe. Note that none of this data has yet been subject to critical review and so no claims are made with respect to ISO-conformance. Unless otherwise stated, the analysis uses the default values shown on page 8 which are still undergoing validation. Until such time as this process of validation, the critical review and the ISO-conformant report are complete, this data shouldn t be used for any analysis to compare the environmental profile of US hardwood lumber against other materials. GWP by species Chart 1 shows variation in GWP for 1 lumber of all 19 species of US hardwood lumber contained in the LCA model. Key points to highlight: Irrespective of species, 1 kg of US hardwood lumber stores the equivalent of kg of carbon dioxide for as long as it is in use. The amount stored per m3 will vary by density. For example 1 m3 of white oak with average density of 769kg/m3 stores 1.23 tonnes CO2 equivalent, while 1 m3 of basswood with average density of 419kg/ m3 stores 0.67 tonnes CO2. equivalent Irrespective of species, carbon storage in product is more than sufficient to offset the GWP of all emissions (from burning of fossil fuels) during forestry, sawmilling, kiln drying and all stages of transport to deliver 1 lumber to the European market. For most species, kiln drying is the dominant factor contributing to GHG emissions. Most variation in GWP between species is due to differences in kiln schedules. This analysis assumes that 90% of energy used in kilning is biomass (and is therefore carbon neutral) while only 10% is derived from fossil fuels. The assumption of relatively high levels of biomass use in the US hardwood lumber sector draws on data from both AHEC members and the CORRIM study and seems robust. However, note that any increase or decrease in the proportion of fossil fuels or electric power used for kilning would have a significant impact on GWP. Impact of transport Chart 2 shows how GWP for 1 KD white oak varies for three different transport scenarios as follows: Shipment to Europe (4800 miles by container ship) with a relatively short road transfer totalling 220 miles by truck (this includes total distance from kiln to US port of export and from European port of import to distributor) Shipment to Europe with a relatively long road transfer totalling 600 miles by truck A worst case scenario of shipment to Australia from the East Coast via Singapore (15500 miles by sea) with a relatively long overland overland transfer of 600 miles by truck. 7

8 Chart 2 shows that GWP is relatively insensitive to changes in transport distance. A near tripling in the distance travelled by truck between the first and second scenarios produces very little change in the overall carbon footprint. Even the worst case scenario involving one of the longest shipping routes Default values used in the LCA The table below shows the default values currently being used for various critical parameters in the LCA model developed for AHEC by PE. This data is still preliminary and needs to be validated with input from a larger proportion of companies involved in the processing of US hardwood lumber for export. Validation is required to ensure data is as representative as possible and to ensure in the world and a road transfer well in excess of the typical distances involved does not produce a particularly dramatic change in carbon footprint. In all scenarios, carbon storage in the lumber continues to greatly out-weigh GWP of all other processes, including transport. Lumber thickness Chart 3 shows how GWP for KD white oak delivered into Europe varies by thickness of the lumber. Due to wide variation in kilning times for this species, GWP is relatively sensitive to lumber thickness. In fact, GHG emissions from burning of fossil fuels during production of 3 white oak lumber are nearly three times the emissions associated with those for 1 lumber. On the other hand, carbon storage is still just sufficient to offset even these emissions. the LCA results conform to ISO standards. To achieve this, AHEC Members are encouraged now to look over the table and to contact AHEC with estimates for their own operations if these differ significantly (please send to msnow@ahec.org). Note that all data supplied by individual companies will remain confidential and that only aggregated average data will ever be published. Produced for the 8